HideShark

Every animal guide

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Mammals LC Aardvark Orycteropus afer The aardvark is a nocturnal African burrower that eats ants and termites with a foot-long sticky tongue, digs faster than several people with shovels, and is the sole survivor of its own mammal order. Read the guide →
Mammals LC Aardwolf Proteles cristata The aardwolf is a small, shy hyena relative that gave up hunting entirely to lick up termites — as many as 300,000 in a night — killing nothing bigger than an insect and drinking no water. Read the guide →
Invertebrates EN Abalone Haliotis An abalone is a large sea snail with an ear-shaped shell lined in shimmering mother-of-pearl, so heavily overharvested for food and shell that several species are now endangered. Read the guide →
Mammals LC Abert's Squirrel Sciurus aberti Abert's squirrel depends almost entirely on ponderosa pine, feeding on its seeds, bark, and buds so consistently that individual squirrels develop personal feeding trees they revisit again and again. Read the guide →
Birds LC Acadian Flycatcher Empidonax virescens The Acadian flycatcher belongs to a genus so visually similar that its explosive, snapping "pizza!" call is often the only reliable way to separate it from several nearly identical relatives. Read the guide →
Amphibians CR Achoque Ambystoma dumerilii An achoque is a Critically Endangered Mexican salamander, a gilled, aquatic cousin of the axolotl that lives in one shrinking lake and is bred by an order of nuns for a traditional cough syrup. Read the guide →
Birds LC Acorn Woodpecker Melanerpes formicivorus The acorn woodpecker drills thousands of holes in one tree and jams an acorn into each, a granary the family guards for generations. It also lives in cooperative groups that nest jointly. Read the guide →
Invertebrates LC Acorn Worm Hemichordata An acorn worm burrows through sand using an acorn-shaped proboscis, and its body carries gill slits similar to those in fish, a clue that has helped trace early steps in vertebrate evolution. Read the guide →
Mammals CR Addax Addax nasomaculatus The addax has been reduced to only a handful of individuals in the wild across the Sahara, a pale, spiral-horned antelope now surviving mainly in captive breeding programs. Read the guide →
Birds LC Adélie Penguin Pygoscelis adeliae The Adélie penguin is the classic tuxedoed penguin of the Antarctic coast — a small, pugnacious bird that walks up to 50 km across sea ice to its rocky colonies and steals stones from its neighbours. Read the guide →
Reptiles LC Aesculapian Snake Zamenis longissimus The Aesculapian snake gave its name to the staff of Asclepius, and its coiled image still appears on ambulances and medical symbols worldwide despite being entirely harmless to humans. Read the guide →
Amphibians LC African Bullfrog Pyxicephalus adspersus The African bullfrog is one of the largest frogs on Earth, a pugnacious ambush predator that eats rodents, birds, and other frogs, guards its tadpoles, and sleeps out droughts underground for years. Read the guide →
Mammals LC African Civet Civettictis civetta The African civet is the largest civet species and, unlike its more arboreal Asian relatives, stays almost entirely on the ground while hunting across the African savanna and forest at night. Read the guide →
Amphibians LC African Clawed Frog Xenopus laevis The African clawed frog is a flat, tongueless, fully aquatic frog that shovels food into its mouth with its hands. It was the first pregnancy test and is now a workhorse of biology labs worldwide. Read the guide →
Mammals LC African Crested Rat Lophiomys imhausi The African crested rat is the only mammal known to borrow a poison from a plant. It chews the bark of the arrow-poison tree and licks the toxin into a strip of wick-like hairs along its flanks. Read the guide →
Mammals EN African Elephant Loxodonta africana The African elephant is the largest land animal alive, with a 40,000-muscle trunk and a 22-month pregnancy. Learn how herds are led by matriarchs and why ivory poaching still threatens them. Read the guide →
Mammals CR African Forest Elephant Loxodonta cyclotis The African forest elephant is a Critically Endangered, smaller and darker elephant of the Congo Basin with straight, downward-pointing tusks, whose seed spreading makes it a gardener of the forest. Read the guide →
Mammals LC African Giant Pouched Rat Cricetomys gambianus The African giant pouched rat is one of the largest rats in the world, and trained individuals are used in Africa to sniff out landmines and tuberculosis. Read the guide →
Mammals VU African Golden Cat Caracal aurata The African golden cat is a secretive, medium-sized rainforest cat of Central and West Africa that comes in coats ranging from golden red to grey, and is closely related to the caracal and serval. Read the guide →
Birds LC African Jacana Actophilornis africanus The African jacana strides across floating lily pads on absurdly long toes, and it flips the usual bird script entirely — females hold territories over several males, who alone incubate the eggs. Read the guide →
Mammals LC African Linsang Poiana richardsonii The African linsang moves through the rainforest canopy with a long, slender body and an even longer ringed tail, hunting small prey almost entirely out of sight above the forest floor. Read the guide →
Fish LC African Lungfish Protopterus annectens The African lungfish breathes air with true lungs and drowns if held underwater. When its swamp dries up it burrows into the mud, wraps itself in a cocoon of mucus, and sleeps for months — or years. Read the guide →
Mammals LC African Palm Civet Nandinia binotata The African palm civet spends nearly its entire life in the trees, an important seed disperser distinct enough that some scientists place it in a family of its own. Read the guide →
Birds CR African Penguin Spheniscus demersus The African penguin produces a loud, braying call resembling a donkey, the only penguin species breeding on the African continent, with a population collapsed by over 95 percent since last century. Read the guide →
Reptiles NT African Rock Python Python sebae The African rock python is the largest snake in Africa, a powerful constrictor. Females coil around their eggs and shiver to keep them warm, then guard the hatchlings for weeks. Read the guide →
Reptiles EN African Spurred Tortoise Centrochelys sulcata The African spurred tortoise is the largest mainland tortoise and third-largest overall, a Sahel grazer that digs burrows 3 metres deep and is now a widely kept — and widely surrendered — pet. Read the guide →
Reptiles LC African Twig Snake Thelotornis capensis The African twig snake is a slender tree snake that mimics a dead branch so well it holds its front third rigid in mid-air for an hour. Its venom disrupts blood clotting and there is no antivenom. Read the guide →
Mammals CR African Wild Ass Equus africanus The African wild ass is the Critically Endangered ancestor of the domestic donkey, a slender, striped-legged desert animal now clinging on in Eritrea and Ethiopia. Read the guide →
Mammals EN African Wild Dog Lycaon pictus The African wild dog is the continent's most efficient large predator — a pack hunter that succeeds in most chases, votes on decisions by sneezing, and cares for its sick and old. Read the guide →
Reptiles NE Agama Agamidae An agama is an Old World lizard of the dragon family — bearded dragons, frilled lizard, water dragons, thorny devil — mostly fast, alert, sun-basking insect hunters. Read the guide →
Amphibians LC Agile Frog Rana dalmatina An agile frog is a slender, long-legged brown frog of European woodland whose two-metre leap is the longest of any European frog, now down to a few protected populations on the Channel Islands. Read the guide →
Mammals LC Agile Wallaby Notamacropus agilis The agile wallaby is the most common and widespread wallaby species across northern Australia, often gathering in larger groups than most of its solitary relatives. Read the guide →
Fish LC Alabama Bass Micropterus henshalli The Alabama bass was only recognised as its own species after genetic study split it from the spotted bass, and its wide stocking has since caused hybridisation problems for other black bass. Read the guide →
Reptiles LC Alabama Map Turtle Graptemys pulchra The Alabama map turtle's females grow dramatically wider heads than males, an adaptation that lets them crush thick-shelled mussels the narrower-jawed males of the same species cannot manage. Read the guide →
Reptiles VU Alabama Red-Bellied Cooter Pseudemys alabamensis The Alabama red-bellied cooter is found nowhere on Earth outside a small stretch of coastal Alabama, making it the state reptile of the one place where it actually lives. Read the guide →
Amphibians NT Alabama Waterdog Necturus alabamensis The Alabama waterdog spends its entire life underwater with feathery external gills fanned out behind its head, found naturally in only a small handful of river systems in Alabama and adjacent states. Read the guide →
Birds EN Albatross Diomedeidae An albatross is a seabird with the longest wingspan of any living bird, able to glide for hours without a wingbeat and live for decades, and most species are now threatened by longline fishing. Read the guide →
Reptiles VU Aldabra Giant Tortoise Aldabrachelys gigantea The Aldabra giant tortoise is the last of the Indian Ocean's giant tortoises, with about 100,000 on one Seychelles atoll. It can top 250 kg and live well past 100 years. Read the guide →
Birds LC Alder Flycatcher Empidonax alnorum The alder flycatcher was only recognized as its own species after researchers realized its "free-beer" song never overlaps with its nearly identical relative, the willow flycatcher. Read the guide →
Invertebrates NE Alderfly Sialidae The alderfly's predatory larva breathes through feathery gills in clean streams and ponds, while the short-lived adult barely feeds at all before dying within days. Read the guide →
Fish LC Alewife Alosa pseudoharengus The alewife migrates from the ocean into freshwater to spawn, but landlocked Great Lakes populations sometimes wash ashore in mass die-offs after sudden temperature shifts. Read the guide →
Amphibians LC Allegheny Mountain Dusky Salamander Desmognathus ochrophaeus The Allegheny Mountain dusky salamander ranges higher up mountain slopes than most of its dusky salamander relatives, often found well away from any stream in damp forest litter. Read the guide →
Reptiles NE Alligator Alligatoridae An alligator is a broad-snouted crocodilian of the Americas and China, and the family, which also includes the caimans, split from true crocodiles around 80 million years ago. Read the guide →
Fish LC Alligator Gar Atractosteus spatula The alligator gar is a living fossil almost unchanged for 100 million years, the biggest fish in the Mississippi at up to 2.7 metres. It is armoured in diamond scales and can gulp air to breathe. Read the guide →
Reptiles LC Alligator Lizard Elgaria An alligator lizard is a long-bodied North American lizard with a stiff, armour-like fold of skin along each side that lets its body expand after a big meal without splitting its scales. Read the guide →
Reptiles VU Alligator Snapping Turtle Macrochelys temminckii The alligator snapping turtle is North America's largest freshwater turtle, a 100 kg ambush predator that fishes by lying still with mouth open and twitching a pink, worm-shaped lure on its tongue. Read the guide →
Mammals LC Alpine Marmot Marmota marmota The alpine marmot lives in family groups on the Alps' high meadows, posts sentinels that whistle at danger, and hibernates huddled together through the winter. Read the guide →
Amphibians LC Alpine Newt Ichthyosaura alpestris The alpine newt is a small European newt with a plain dark back and a vivid unmarked orange belly. Breeding males turn steel-blue, and some mountain populations never lose their larval gills. Read the guide →
Amphibians LC Alpine Salamander Salamandra atra The alpine salamander is a jet-black mountain amphibian that never enters water, even to breed, and is pregnant for two to four years before giving birth to fully formed young. Read the guide →
Mammals EN Amami Rabbit Pentalagus furnessi The Amami rabbit is a living fossil found only on two Japanese islands, a primitive rabbit lineage that gives birth inside a burrow rather than a simple surface nest like most of its relatives. Read the guide →
Amphibians VU Amargosa Toad Anaxyrus nelsoni The Amargosa toad survives within one short stretch of desert river in Nevada, a population so confined that local ranchers and conservationists work together to keep its springs intact. Read the guide →
Birds LC Amazon Kingfisher Chloroceryle amazona The Amazon kingfisher is the largest of the green-backed American kingfishers, favouring the wider rivers that its smaller relative the green kingfisher tends to avoid. Read the guide →
Amphibians LC Amazon Milk Frog Trachycephalus resinifictrix The Amazon milk frog is a large, marbled canopy tree frog named for the sticky white poison it oozes when handled. It breeds only in tree-hole water, and the tadpoles will eat each other. Read the guide →
Mammals EN Amazon River Dolphin Inia geoffrensis The Amazon river dolphin can turn pink as it matures, the largest river dolphin in the world, navigating flooded forest and murky river water almost entirely by sound rather than sight. Read the guide →
Reptiles LC Amazon Tree Boa Corallus hortulana The Amazon tree boa shows an extraordinary range of colour variation between individuals, from grey and brown to vivid orange and red, all within the same species. Read the guide →
Invertebrates NE Amazonian Giant Centipede Scolopendra gigantea The Amazonian giant centipede grows past 30 cm and hunts tarantulas, lizards, frogs, and mice. In one Venezuelan cave it hangs from the ceiling and snatches bats out of the air. Read the guide →
Mammals VU Amazonian Manatee Trichechus inunguis The Amazonian manatee is the only manatee species living entirely in fresh water, spending its whole life within the Amazon River basin rather than ever entering the ocean its coastal relatives need. Read the guide →
Fish LC Amberjack Seriola dumerili The amberjack is a large, powerful reef predator nicknamed the reef donkey by anglers for its stubborn fighting strength, a popular sport fish carrying a real food safety risk in some waters. Read the guide →
Invertebrates LC Ambush Bug Phymatidae The ambush bug waits motionless on a flower petal, camouflaged well enough that pollinating insects land right beside it, then seizes prey many times its size with thickened, raptorial front legs. Read the guide →
Reptiles LC American Alligator Alligator mississippiensis The American alligator is a freshwater ambush predator and an ecosystem engineer whose "gator holes" keep wetlands alive. Learn how it survives freezing water and how it came back from the brink. Read the guide →
Birds LC American Avocet Recurvirostra americana The American avocet sweeps its long, distinctly upturned bill side to side through shallow water like a scythe, feeling for prey rather than looking for it directly. Read the guide →
Mammals LC American Badger Taxidea taxus The American badger can dig a rodent out of its own burrow faster than the rodent can escape, a powerful digger that sometimes teams up with hunting coyotes in a genuine cross-species partnership. Read the guide →
Mammals NT American Bison Bison bison The American bison is North America's largest land animal and its greatest conservation comeback — from tens of millions to a few hundred, and back. Learn how it shapes the prairie. Read the guide →
Birds LC American Bittern Botaurus lentiginosus The American bittern is a heron that hides in the reeds by freezing with its bill pointed straight up, and whose deep pumping boom carries across a marsh at dusk. Read the guide →
Mammals LC American Black Bear Ursus americanus The American black bear is the most common bear in the world — a shy, adaptable forest omnivore that mostly eats plants, climbs well, and rarely attacks despite living near millions of people. Read the guide →
Amphibians LC American Bullfrog Lithobates catesbeianus The American bullfrog is the largest frog in North America, a sit-and-wait predator that eats anything it can swallow — and one of the world's most damaging invasive amphibians. Read the guide →
Invertebrates LC American Cockroach Periplaneta americana The American cockroach is one of the largest roaches to live alongside people, it is not American but African, it can run 50 body lengths a second, and it can survive about a week without its head. Read the guide →
Birds LC American Coot Fulica americana The American coot swims with lobed rather than webbed toes, an unusual adaptation among waterbirds, while chicks flash a shock of orange fuzz that parents seem to specifically favour when feeding. Read the guide →
Invertebrates LC American Copper Lycaena phlaeas The American copper flashes a metallic, fiery orange sheen across its wings, a colour striking enough at close range to have given the entire copper butterfly family its common name. Read the guide →
Reptiles VU American Crocodile Crocodylus acutus The American crocodile is a large, salt-tolerant crocodile of the Americas that is far shyer than its Old World relatives. It recovered from near-extinction in Florida to become a conservation win. Read the guide →
Birds LC American Crow Corvus brachyrhynchos The American crow is a glossy black bird of North America known for its harsh caw, its winter roosts of thousands, and its ability to remember and hold a grudge against individual people. Read the guide →
Birds LC American Dipper Cinclus mexicanus The American dipper is the only songbird in North America that swims, walking along the beds of fast mountain streams and diving underwater to hunt insect larvae year-round. Read the guide →
Fish EN American Eel Anguilla rostrata The American eel lives most of its life in fresh water, then travels to the Sargasso Sea to breed and die, the exact reverse of a salmon's migration. Read the guide →
Amphibians LC American Green Tree Frog Dryophytes cinereus The American green tree frog is the bright green, gold-flecked frog of the US Southeast, with sticky toe pads for climbing glass and a loud, bell-like 'quonk' call that fills summer nights near water. Read the guide →
Birds LC American Kestrel Falco sparverius The American kestrel is North America's smallest and most common falcon, a colourful jay-sized raptor that hovers over fields hunting insects and voles, and has been quietly declining for decades. Read the guide →
Invertebrates LC American Lady Vanessa virginiensis The American lady builds a distinctive silk-and-leaf shelter for its caterpillar to hide in while feeding, a protective structure its close relative, the more widespread painted lady, does not build. Read the guide →
Mammals LC American Marten Martes americana The American marten depends so closely on dense, structurally complex forest that logging alone can eliminate it even when plenty of prey remains, a slender hunter tied tightly to old forest. Read the guide →
Mammals LC American Mink Neovison vison The American mink hunts both on land and underwater along streams and marshes, a fierce predator whose introduction to Europe made it one of the more disruptive invasive carnivores there. Read the guide →
Birds LC American Oystercatcher Haematopus palliatus The American oystercatcher uses one of two distinct bill techniques, stabbing a shellfish before it can clamp shut or hammering it open, and a chick learns which method by watching its own parents. Read the guide →
Fish VU American Paddlefish Polyodon spathula The American paddlefish swims mouth-open, straining zooplankton like a tiny whale. Its long paddle snout is covered in electroreceptors that map prey swarms. It is a toothless cousin of the sturgeon. Read the guide →
Mammals LC American Pika Ochotona princeps The American pika spends short mountain summers gathering huge haypiles to survive under deep snow. It has no tolerance for heat and can die within hours if trapped in direct summer sun. Read the guide →
Mammals LC American Red Squirrel Tamiasciurus hudsonicus The American red squirrel defends a conifer-stocked territory year-round with loud, persistent scolding, a small, feisty forager whose central cone cache can grow large enough to last generations. Read the guide →
Birds LC American Redstart Setophaga ruticilla The American redstart flashes bold orange or yellow tail and wing patches while foraging, a display thought to startle hidden insects into moving and giving away their position. Read the guide →
Birds LC American Robin Turdus migratorius The American robin is the orange-breasted thrush of North American lawns — a bird that finds worms partly by ear, can get drunk on fermented berries, and heralds spring with its song. Read the guide →
Invertebrates LC American Rubyspot Hetaerina americana The American rubyspot flashes a patch of deep ruby-red at the base of each wing, a colour bold enough to catch sunlight from across a stream and give this damselfly a striking appearance. Read the guide →
Invertebrates LC American Snout Libytheana carinenta The American snout is named for elongated mouthparts that project forward like a tiny beak, and in Texas it has staged some of the largest butterfly migrations ever documented in North America. Read the guide →
Amphibians LC American Toad Anaxyrus americanus The American toad is a warty backyard toad of eastern North America whose long trilling call rings from ponds each spring. Its glands ooze a toxin that makes dogs foam and drop it. Read the guide →
Mammals LC American Water Shrew Sorex palustris The American water shrew can run briefly across the surface of water, trapped air bubbles under its fringed feet keeping it from sinking for a few crucial seconds. Read the guide →
Birds LC American Woodcock Scolopax minor The American woodcock is a shorebird that lives in the forest, with eyes set so far back it can see behind itself, a bill that probes soil for worms, and a rocking walk that made it an internet star. Read the guide →
Reptiles LC Amethystine Python Simalia amethistina The amethystine python is Australia's largest native snake, a powerful constrictor whose smooth scales flash an iridescent purple sheen in direct sunlight, the source of its gemstone-inspired name. Read the guide →
Invertebrates LC Amphipod Amphipoda An amphipod is a small, flattened crustacean found in nearly every aquatic and damp habitat on Earth, and the beach-dwelling kind can launch itself into the air by snapping its curled body straight. Read the guide →
Amphibians NE Amphiuma Amphiumidae An amphiuma is an eel-like aquatic salamander of the US Southeast with four tiny useless legs, a painful bite, and a red blood cell so large it is a standard biology teaching specimen. Read the guide →
Birds CR Amsterdam Albatross Diomedea amsterdamensis The Amsterdam albatross breeds nowhere on Earth except a single plateau on one remote island, with a total population of only around a hundred and seventy birds remaining. Read the guide →
Reptiles LC Anaconda Eunectes An anaconda is a giant South American boa that hunts from the water, killing by constriction, and the green anaconda is the heaviest snake in the world, though the reticulated python grows longer. Read the guide →
Fish LC Anchovy Engraulidae An anchovy is a silvery schooling fish that strains plankton from coastal water, and the Peruvian anchoveta has in some years been Earth's largest fishery, feeding mostly farmed fish and livestock. Read the guide →
Birds LC Andean Cock-of-the-rock Rupicola peruvianus The male Andean cock-of-the-rock is vividly coloured, a blazing orange body topped by a half-moon crest. Males gather at shared display grounds to compete for females with elaborate dances. Read the guide →
Birds VU Andean Condor Vultur gryphus The Andean condor has the largest wing area of any land bird — over 3 metres across — and can soar 160 km without a single flap. It is the national bird of four countries and lives up to 70 years. Read the guide →
Birds VU Andean Flamingo Phoenicoparrus andinus The Andean flamingo is the rarest flamingo species in the world, breeding on remote high-altitude salt flats where thin air and freezing nights make survival a genuine challenge. Read the guide →
Birds LC Andean Flicker Colaptes rupicola The Andean flicker is a ground-foraging woodpecker of the high Andes, digging nest burrows into earthen banks rather than excavating cavities in wood like most of its relatives. Read the guide →
Birds LC Andean Goose Chloephaga melanoptera The Andean goose lives at higher altitude than any of its Patagonian relatives, grazing the edges of high-Andean lakes and bogs thousands of metres above sea level. Read the guide →
Birds LC Andean Hillstar Oreotrochilus estella The Andean hillstar forages at extreme altitude where the air holds far less oxygen, entering a state of deep torpor overnight to survive freezing temperatures no other hummingbird could withstand. Read the guide →
Birds LC Andean Lapwing Vanellus resplendens The Andean lapwing lives at extreme high altitude across the Andes, its pale grey plumage offering camouflage against the rocky terrain of its cold mountain habitat. Read the guide →
Mammals EN Andean Mountain Cat Leopardus jacobita The Andean mountain cat is one of the rarest wild cats on Earth, hunting mountain vizcachas across the thin air of the high Andes above 4,000 metres. Read the guide →
Amphibians LC Andean Toad Rhinella spinulosa The Andean toad tolerates some of the highest elevations of any toad species in the world, ranging across a vast stretch of the Andes from Peru down into Patagonia. Read the guide →
Mammals DD Andrews' Beaked Whale Mesoplodon bowdoini Andrews' beaked whale is one of the least documented marine mammals in the Southern Hemisphere, known almost entirely from a small number of strandings rather than any confirmed sighting at sea. Read the guide →
Reptiles CR Anegada Iguana Cyclura pinguis The Anegada iguana is a large, pale rock iguana found naturally only on the flat island of Anegada in the British Virgin Islands, once nearly extinct and now recovering through a head-start programme. Read the guide →
Fish CR Angel Shark Squatinidae The angel shark has a flattened, ray-like body that lets it bury itself in sand, ambushing passing prey with a sudden upward lunge and snap rather than actively chasing it down. Read the guide →
Fish NE Angelicus Catfish Synodontis angelicus The angelicus catfish is covered in bold white spots against a dark body, often swimming upside down to graze food from the underside of logs and leaves. Read the guide →
Fish LC Anglerfish Melanocetus johnsonii The deep-sea anglerfish lures prey with a glowing rod on its head in water with no sunlight, and the tiny male fuses permanently to the huge female, becoming a living sperm supply. Read the guide →
Reptiles DD Angolan Python Python anchietae The Angolan python is one of Africa's least-known pythons, a smaller, arid-adapted relative of the African rock python restricted to a narrow, rocky stretch of southwestern Africa. Read the guide →
Mammals LC Angwantibo Arctocebus calabarensis The angwantibo specializes in eating hairy, chemically defended caterpillars that most other predators avoid entirely, moving through the canopy in near silence. Read the guide →
Birds LC Anhinga Anhinga anhinga The anhinga swims almost submerged, only its snaking neck showing, spears fish with a lightning bill-thrust, then perches with wings spread wide to dry its deliberately non-waterproof feathers. Read the guide →
Birds LC Anna's Hummingbird Calypte anna Anna's hummingbird males perform a dramatic courtship dive, climbing high before plunging downward and pulling up sharply enough that specialized tail feathers produce a loud chirp from airflow alone. Read the guide →
Fish LC Annular Seabream Diplodus annularis The annular seabream is a small, silvery sea bream of Mediterranean and eastern Atlantic seagrass beds and sandy bottoms, named for the black ring around the base of its tail. Read the guide →
Reptiles NE Anole Dactyloidae An anole is a small New World lizard with sticky toe pads and a colourful throat fan it flashes to signal; the 400-plus species keep re-evolving the same forms island by island. Read the guide →
Invertebrates NE Ant Formicidae An ant is a member of a colony that works as a single superorganism — a long-lived queen and a sterile female workforce — and the world's ants weigh about as much as all wild birds and mammals. Read the guide →
Mammals LC Antarctic Fur Seal Arctocephalus gazella The Antarctic fur seal was hunted to near extinction by the early 1900s, then rebounded so dramatically it is now one of the most abundant seals in the Southern Ocean, numbering in the millions. Read the guide →
Invertebrates NE Antarctic Krill Euphausia superba Antarctic krill is a small shrimp-like crustacean of the Southern Ocean that swarms in the billions, feeds the whales, seals, and penguins of Antarctica, and grazes algae on the underside of sea ice. Read the guide →
Invertebrates LC Antarctic Limpet Nacella concinna The Antarctic limpet dominates grazing across the Antarctic intertidal zone, scraping algae from rock surfaces despite the constant threat of being crushed by drifting sea ice. Read the guide →
Mammals NT Antarctic Minke Whale Balaenoptera bonaerensis The Antarctic minke whale ventures deeper into pack ice than almost any other baleen whale, following narrow leads and cracks through the frozen Southern Ocean in search of krill. Read the guide →
Birds LC Antarctic Petrel Thalassoica antarctica The Antarctic petrel breeds further south than almost any flying bird, forming enormous colonies on exposed rock outcrops deep within the continent, hundreds of kilometres from open water. Read the guide →
Birds LC Antarctic Prion Pachyptila desolata The Antarctic prion filters tiny planktonic crustaceans directly from the sea surface using comb-like structures lining its bill, feeding in some of the largest flocks of any Southern Ocean seabird. Read the guide →
Fish LC Antarctic Rockcod Notothenia coriiceps The Antarctic rockcod is one of the most studied fish species around the Antarctic Peninsula, tolerating a wider range of temperatures than many of its more narrowly specialised relatives. Read the guide →
Invertebrates LC Antarctic Scallop Adamussium colbecki The Antarctic scallop grows unusually large and lives unusually long for a bivalve, a slow-metabolism strategy that lets it thrive on the cold, food-limited Antarctic seafloor. Read the guide →
Invertebrates LC Antarctic Sea Spider Colossendeis megalonyx The Antarctic sea spider grows far larger than its warm-water relatives, a striking example of polar gigantism linked to how efficiently oxygen dissolves in cold Southern Ocean water. Read the guide →
Invertebrates LC Antarctic Sea Star Odontaster validus The Antarctic sea star is one of the most abundant predators and scavengers on the Antarctic seafloor, feeding on almost anything it can find and playing an outsized role in the local food web. Read the guide →
Invertebrates LC Antarctic Sea Urchin Sterechinus neumayeri The Antarctic sea urchin is one of the most common and widely studied invertebrates of the Antarctic seafloor, grazing algae and scavenging detritus across a remarkably broad depth range. Read the guide →
Fish LC Antarctic Silverfish Pleuragramma antarcticum The Antarctic silverfish is one of the most important prey species in the Southern Ocean food web, feeding an enormous range of penguins, seals, toothfish, and whales despite its own small size. Read the guide →
Birds LC Antarctic Tern Sterna vittata The Antarctic tern breeds on islands and coastlines right around the Southern Ocean, diving for small fish close to shore and staying within the Southern Hemisphere year-round. Read the guide →
Fish LC Antarctic Toothfish Dissostichus mawsoni The Antarctic toothfish produces natural antifreeze proteins that keep its blood from freezing in sub-zero Southern Ocean water, growing large enough to become key prey for colossal squid and seals. Read the guide →
Birds LC Antbird Thamnophilidae An antbird follows swarming army ants through the rainforest, not to eat the ants themselves but to snatch up the insects and small creatures the ants flush out of hiding as they march. Read the guide →
Mammals LC Antelope Jackrabbit Lepus alleni The antelope jackrabbit bounds across the desert with leaps reminiscent of an antelope, using enormous ears to shed excess heat in one of the hottest habitats any hare calls home. Read the guide →
Fish LC Anthias Pseudanthias The anthias forms large, colourful schools over reef drop-offs, with a single dominant male guarding a harem of females that can themselves change sex if that male disappears. Read the guide →
Reptiles CR Antiguan Racer Alsophis antiguae The Antiguan racer is a slender, non-venomous snake once called the world's rarest, which was rescued from near-extinction on a tiny island off Antigua by removing the rats that preyed on it. Read the guide →
Birds EN Antipodean Albatross Diomedea antipodensis The Antipodean albatross was split from the wandering albatross as its own species, and its females have declined sharply after ranging into fishing grounds worked by longline tuna fleets. Read the guide →
Invertebrates NE Antlion Myrmeleontidae The antlion larva digs a conical pit in dry sand and buries itself at the bottom with only its jaws showing, flicking sand to trigger avalanches that drag prey down. Adults resemble weak dragonflies. Read the guide →
Birds LC Antpitta Grallaria An antpitta looks almost like a ball on two long legs, a round-bodied, nearly tailless forest-floor bird so hidden that many species were only recently coaxed into view with earthworms. Read the guide →
Amphibians LC Apalachicola Dusky Salamander Desmognathus apalachicolae The Apalachicola dusky salamander occupies a narrow stretch of ravine and seepage habitat along one river system, tying its survival to the health of a handful of specific streams. Read the guide →
Mammals EN Ape Hominoidea An ape is a tailless primate with a shoulder built for swinging under branches, split into the small, singing gibbons and the great apes, orangutans, gorillas, chimpanzees, bonobos, and humans. Read the guide →
Invertebrates NE Aphid Aphididae The aphid can give birth to genetically identical live young without ever mating, letting a single founder explode into an entire colony within days. Read the guide →
Birds LC Aplomado Falcon Falco femoralis The aplomado falcon is a fast, agile hunter of open grassland stretching from the southern United States to Patagonia, often working in pairs to flush and catch birds in cooperative low-level chases. Read the guide →
Birds LC Arabian Woodpecker Dendrocopos dorae The Arabian woodpecker survives in a handful of mountain woodlands across southwestern Arabia, one of the few woodpeckers anywhere adapted to such an arid, isolated corner of the world. Read the guide →
Fish DD Arapaima Arapaima gigas The arapaima is one of the largest freshwater fish alive — up to 3 metres and 200 kg — and it must surface every 5 to 15 minutes to breathe air, gulping with a loud cough that hunters listen for. Read the guide →
Amphibians LC Arboreal Salamander Aneides lugubris The arboreal salamander is a lungless California salamander built for climbing, with a gripping tail and square toe tips; it lives high in oak and redwood canopies and bites hard enough to draw blood. Read the guide →
Fish LC Archerfish Toxotes jaculatrix The archerfish hunts by spitting a precise jet of water to knock insects off overhanging leaves — correcting for the way light bends at the surface, and learning the skill by watching other fish. Read the guide →
Amphibians CR Archey's Frog Leiopelma archeyi Archey's frog is one of the most ancient frogs alive, barely changed in 150 million years. It has no eardrum, skips the tadpole stage, and the father carries the froglets on his back. Read the guide →
Fish LC Arctic Char Salvelinus alpinus The Arctic char lives further north than any other freshwater fish on Earth, with some populations spawning in near-freezing water and others trapped in lakes since the last ice age. Read the guide →
Mammals LC Arctic Fox Vulpes lagopus The Arctic fox has the warmest fur of any mammal, changes colour with the seasons, and can raise a litter of 18 in a lemming boom. Learn how it survives −50 °C and follows polar bears for scraps. Read the guide →
Fish LC Arctic Grayling Thymallus arcticus The Arctic grayling carries an enormous, sail-like dorsal fin far larger than almost any other freshwater fish its size, displayed by males during courtship in the cold, clear rivers of the far north. Read the guide →
Mammals LC Arctic Ground Squirrel Urocitellus parryii The Arctic ground squirrel is the only mammal known to let its body cool below freezing, dropping to minus three degrees Celsius during its eight-month hibernation without turning to ice. Read the guide →
Mammals LC Arctic Shrew Sorex arcticus The arctic shrew wears three distinct shades across its body, a dark saddle down the back fading to paler sides and belly, despite living well south of the true Arctic across much of its range. Read the guide →
Birds LC Arctic Tern Sterna paradisaea The Arctic tern makes the longest migration of any animal — a zigzag round trip of up to 90,000 km a year between the Arctic and Antarctic, so it sees two summers and endless daylight. Read the guide →
Mammals NT Argali Ovis ammon The argali is the largest wild sheep in the world, with males carrying massive curling horns that can weigh nearly as much as the rest of their skeleton combined. Read the guide →
Amphibians NT Argentine Horned Frog Ceratophrys ornata The Argentine horned frog is a nearly circular, all-mouth ambush predator that lunges at anything it can fit its jaws around, including prey its own size, and bites hard for a frog. Read the guide →
Reptiles LC Argentine Tegu Salvator merianae The Argentine tegu is a large, intelligent lizard that warms its own body several degrees above its surroundings during the breeding season, a partial form of the warm-bloodedness seen in mammals. Read the guide →
Invertebrates LC Argonaut Argonauta argo The argonaut is a small open-ocean octopus whose female builds a thin shell as an egg case and diving weight, while the tiny male's mating arm detaches and swims off on its own. Read the guide →
Reptiles LC Argus Monitor Varanus panoptes The argus monitor digs extensive burrow systems and raids crocodile nests for eggs, one of Australia's largest and most adaptable monitor lizards. Read the guide →
Invertebrates LC Arizona Bark Scorpion Centruroides sculpturatus The Arizona bark scorpion is the most venomous scorpion in North America and the only one there whose sting is a real danger; it also climbs walls, hides in shoes, and glows under ultraviolet light. Read the guide →
Amphibians NT Arizona Toad Anaxyrus microscaphus The Arizona toad depends on clean, flowing desert streams rather than the still ponds most toads favour, making it unusually vulnerable to the damming and diversion projects reshaping the Southwest. Read the guide →
Amphibians LC Arizona Treefrog Dryophytes wrightorum The Arizona treefrog waits out most of the year underground, then breeds explosively in temporary rain pools the moment the summer monsoon arrives. Read the guide →
Reptiles LC Armadillo Girdled Lizard Ouroborus cataphractus When threatened, the armadillo girdled lizard bites its own tail and curls into a spiny armoured ring, protecting its soft belly like an armadillo. It is one of few lizards that gives live birth. Read the guide →
Invertebrates NE Army Ant Eciton burchellii Army ants build no permanent nest. A colony of up to a million marches through the rainforest in raiding swarms, then links legs to form a living nest — walls, chambers and all — out of ant bodies. Read the guide →
Mammals DD Arnoux's Beaked Whale Berardius arnuxii Arnoux's beaked whale is the southern counterpart to Baird's beaked whale, diving to extreme depths in the cold waters around Antarctica and remaining one of the least studied whale species on Earth. Read the guide →
Fish EN Arowana Osteoglossidae An arowana is a long freshwater fish that leaps from the water to grab insects and birds off branches, mouthbroods its young, and, as the Asian dragon fish, sells for tens of thousands of dollars. Read the guide →
Invertebrates LC Arrow Crab Stenorhynchus seticornis The arrow crab moves on impossibly thin, spider-like legs with a sharply pointed head, and reef aquarium keepers prize it specifically for hunting down troublesome bristle worms. Read the guide →
Invertebrates LC Arrow Worm Chaetognatha An arrow worm is a nearly transparent, torpedo-shaped ocean predator that grabs prey with curved spines around its mouth in one of the fastest strikes of any small marine animal. Read the guide →
Amphibians EN Arroyo Toad Anaxyrus californicus The arroyo toad depends on a specific kind of California streambed, open sandy terraces that flood and reshape naturally, a habitat dams and development have made hard to find. Read the guide →
Reptiles CR Aruba Island Rattlesnake Crotalus unicolor The Aruba Island rattlesnake is a pale, venomous rattlesnake found only on the Caribbean island of Aruba, one of the rarest rattlesnakes in the world and Critically Endangered. Read the guide →
Birds LC Ash-Throated Flycatcher Myiarchus cinerascens The ash-throated flycatcher nests inside abandoned woodpecker holes and old cactus cavities, often lining the chamber with shed snake skin rather than building anything from scratch. Read the guide →
Invertebrates LC Ashy Mining Bee Andrena cineraria The ashy mining bee is a striking black solitary bee with two broad grey-white bands of hair that digs nest burrows in bare ground and short turf and is parasitised by a cuckoo bee. Read the guide →
Birds LC Ashy-headed Goose Chloephaga poliocephala The ashy-headed goose is a forest-edge specialist among the Patagonian geese, grazing at woodland margins rather than the open grassland or shoreline favoured by several of its close relatives. Read the guide →
Mammals EN Asian Elephant Elephas maximus The Asian elephant is smaller-eared than its African cousin and more closely related to the extinct mammoth. Fewer than 50,000 remain, and most of the world's working elephants are this species. Read the guide →
Invertebrates NE Asian Giant Hornet Vespa mandarinia The Asian giant hornet is the world's largest hornet, a 4–5 cm predator whose scouts mark a honeybee hive and then return as a squad that can behead 30,000 bees in a few hours. Read the guide →
Mammals LC Asian House Shrew Suncus murinus The Asian house shrew lives alongside people in towns and villages across much of Asia, announcing its presence with a strong musky odour and a distinctive chattering call. Read the guide →
Invertebrates NE Asian Lady Beetle Harmonia axyridis The Asian lady beetle was deliberately released to eat crop-damaging aphids, and it succeeded so well that it now outcompetes native ladybirds and swarms into houses by the thousands each autumn. Read the guide →
Invertebrates NE Asian Longhorned Beetle Anoplophora glabripennis The Asian longhorned beetle bores deep into healthy hardwood trees rather than dead ones, making it one of the most economically destructive invasive forest pests in North America and Europe. Read the guide →
Fish DD Asian Sheepshead Wrasse Semicossyphus reticulatus The Asian sheepshead wrasse is a metre-long reef fish with a bulbous forehead and jutting chin. Every one starts life female, and the largest can switch to male, taking on the big head and a harem. Read the guide →
Mammals VU Asian Small-Clawed Otter Aonyx cinereus The Asian small-clawed otter is the smallest otter species in the world, using unusually dexterous, only partly webbed paws to feel for shellfish and crabs rather than relying on sight. Read the guide →
Reptiles LC Asian Vine Snake Ahaetulla The Asian vine snake is a pencil-thin green snake with horizontal keyhole-shaped pupils, unique among snakes. Grooved binocular vision lets it judge distance well enough to strike moving lizards. Read the guide →
Reptiles LC Asian Water Monitor Varanus salvator The Asian water monitor is the second-longest lizard on Earth after the Komodo dragon — a semi-aquatic generalist that thrives in cities, canals, and mangroves across South and Southeast Asia. Read the guide →
Mammals VU Asiatic Black Bear Ursus thibetanus The Asiatic black bear, or moon bear, is a Vulnerable Asian forest bear with a pale crescent on its chest that climbs trees to feed and is hunted for its parts across much of its range. Read the guide →
Amphibians LC Asiatic Toad Bufo gargarizans The Asiatic toad has long been harvested for traditional Chinese medicine, its dried skin secretions processed into remedies, making it one of the more economically significant toads. Read the guide →
Reptiles LC Asp Viper Vipera aspis The asp viper is a small, variable venomous snake of sunny rocky slopes in western Europe, with a slightly upturned snout and a zigzag pattern, found from the Pyrenees to the Alps. Read the guide →
Invertebrates NE Assassin Bug Reduviidae Assassin bugs stab prey with a curved beak, inject saliva that liquefies the insides, and drink it dry. Some stack the husks of their victims on their backs as camouflage; a few suck human blood. Read the guide →
Invertebrates NE Assassin Snail Clea helena The assassin snail hunts and eats other snails, often kept deliberately in aquariums to control outbreaks of smaller pest snail species that reproduce out of control. Read the guide →
Fish LC Atlantic Bluefin Tuna Thunnus thynnus The Atlantic bluefin tuna is a warm-blooded ocean sprinter that can weigh 700 kg, cross the Atlantic in weeks, and sell for over a million dollars a fish — which nearly wiped it out. Read the guide →
Amphibians NT Atlantic Coast Leopard Frog Lithobates kauffeldi The Atlantic Coast leopard frog was hiding in plain sight around New York City for decades, only formally recognized as its own species in 2014 after its distinct call gave it away. Read the guide →
Amphibians LC Atlantic Coast Slimy Salamander Plethodon chlorobryonis The Atlantic Coast slimy salamander is one of more than a dozen nearly identical species that emerged when genetic study split apart the old, broadly defined slimy salamander complex. Read the guide →
Fish VU Atlantic Cod Gadus morhua The Atlantic cod once existed off Newfoundland in numbers so vast that explorers described dipping baskets into the sea to catch them. Overfishing collapsed the stock so badly it never recovered. Read the guide →
Fish EN Atlantic Halibut Hippoglossus hippoglossus The Atlantic halibut is the largest flatfish in the world, starting life with an eye on each side before one migrates across as it matures. Overfishing has driven it down sharply. Read the guide →
Invertebrates VU Atlantic Horseshoe Crab Limulus polyphemus The Atlantic horseshoe crab is a living fossil older than the dinosaurs, more closely related to spiders than to crabs. Its bright blue blood is used to test almost every injectable drug on Earth. Read the guide →
Fish LC Atlantic Mackerel Scomber scombrus The Atlantic mackerel is a fast, streamlined schooling fish of the North Atlantic, marked with wavy black bars on a blue-green back, that has no swim bladder and must keep swimming to breathe. Read the guide →
Fish LC Atlantic Menhaden Brevoortia tyrannus The Atlantic menhaden is an oily, bony filter-feeding fish that almost nobody eats directly but that feeds striped bass, whales, and ospreys, and is ground up by the millions of tons. Read the guide →
Fish LC Atlantic Mudskipper Periophthalmus barbarus The Atlantic mudskipper is a fish that spends most of its life out of water, walking on its fins across mudflats, breathing through its skin and mouth, and defending a burrow it digs with its jaws. Read the guide →
Birds EN Atlantic Petrel Pterodroma incerta The Atlantic petrel breeds almost entirely on a single island where introduced house mice have evolved into unusually large, aggressive predators that attack chicks in their nests. Read the guide →
Birds VU Atlantic Puffin Fratercula arctica The Atlantic puffin is a small seabird that flies underwater to catch fish, carries dozens of them crosswise in its bill, and spends most of the year alone far out on the open ocean. Read the guide →
Fish LC Atlantic Salmon Salmo salar The Atlantic salmon hatches in a river, migrates thousands of kilometres out to sea, then navigates back to its birth stream to spawn — guided by the Earth's magnetic field and by smell. Read the guide →
Fish EN Atlantic Sturgeon Acipenser oxyrinchus The Atlantic sturgeon is an armoured, bony-plated fish whose lineage stretches back over 100 million years. Its roe once fuelled a caviar boom so intense it nearly wiped the species out. Read the guide →
Fish VU Atlantic Tarpon Megalops atlanticus The Atlantic tarpon, the silver king, is a giant coastal game fish clad in huge mirror-like scales. It gulps air at the surface to breathe and leaps clear of the water when hooked. Read the guide →
Mammals LC Atlantic White-Sided Dolphin Leucopleurus acutus The Atlantic white-sided dolphin tolerates colder water than many relatives, a robust, boldly patterned species of the cool North Atlantic that often travels in mixed groups with other whales. Read the guide →
Fish LC Atlantic Wolffish Anarhichas lupus The Atlantic wolffish looks fearsome — fangs and grinding plates in a blunt head — but it uses those teeth on sea urchins and clams, and makes its own antifreeze to survive near-freezing water. Read the guide →
Birds EN Atlantic Yellow-nosed Albatross Thalassarche chlororhynchos The Atlantic yellow-nosed albatross is the smallest of the mollymawk albatrosses, identified by a thin yellow stripe running along the ridge of its otherwise black bill. Read the guide →
Invertebrates LC Atlas Moth Attacus atlas The atlas moth is one of the largest insects on Earth, with a wingspan up to 30 cm. The adult has no mouth and never eats — it lives about a week on stored energy, purely to find a mate. Read the guide →
Invertebrates NE Atolla Jellyfish Atolla wyvillei The atolla jellyfish is a deep-sea jellyfish that, when attacked, spins a pinwheel of blue light around its bell — thought to summon a bigger predator to attack whatever is attacking the jelly. Read the guide →
Birds NT Auckland Shag Leucocarbo colensoi The Auckland shag breeds only around New Zealand's remote Auckland Islands, diving to considerable depths for bottom-dwelling fish along one of the least visited coastlines in the Southern Ocean. Read the guide →
Amphibians EN Austin Blind Salamander Eurycea waterlooensis The Austin blind salamander lives only within the deep aquifer water beneath a single Texas spring complex and was not formally described until 2001. Read the guide →
Birds LC Austral Blackbird Curaeus curaeus The austral blackbird forages in noisy flocks across Chilean farmland and forest edge, its glossy black plumage flashing a faint purple sheen in sunlight. Read the guide →
Birds LC Austral Canastero Asthenes anthoides The austral canastero ranges further south into Patagonian scrub and forest edge than several of its canastero relatives, weaving the same distinctive domed stick nests shared across the group. Read the guide →
Birds LC Austral Negrito Lessonia rufa The austral negrito shows one of the sharpest differences between the sexes of any Patagonian songbird, males jet black with a white wing patch, females a plain brown. Read the guide →
Birds LC Austral Parakeet Enicognathus ferrugineus The austral parakeet is the southernmost parrot species in the world, surviving in the cold southern beech forests of Tierra del Fuego far beyond the range of any other parrot on Earth. Read the guide →
Birds LC Austral Pygmy-owl Glaucidium nano The austral pygmy-owl hunts during daylight hours unlike most owls, its false eye markings on the back of its head confusing small birds that try to mob it from behind. Read the guide →
Birds LC Austral Thrush Turdus falcklandii The austral thrush thrives everywhere from Falkland Islands pasture to city parks in southern Chile, one of the most adaptable and widespread songbirds found anywhere in southern South America. Read the guide →
Fish EN Australian Lungfish Neoceratodus forsteri The Australian lungfish is a heavy, olive-scaled river fish of Queensland that has barely changed in 100 million years and can breathe air through a single lung when its pool runs low on oxygen. Read the guide →
Mammals EN Australian Sea Lion Neophoca cinerea The Australian sea lion has one of the longest, most irregular breeding cycles of any pinniped, varying considerably between colonies rather than following the predictable annual timing of most seals. Read the guide →
Amphibians CR Axolotl Ambystoma mexicanum The axolotl is a salamander that never grows up — it keeps its gills and stays underwater for life, and it can regrow lost limbs. Learn why it's beloved in labs and nearly extinct in the wild. Read the guide →
Mammals EN Aye-Aye Daubentonia madagascariensis The aye-aye is a nocturnal Madagascan lemur with rodent-like teeth and a long ball-jointed middle finger that it taps on wood to find grubs by echo, then hooks them out — the woodpecker's niche. Read the guide →
Invertebrates LC Azure Damselfly Coenagrion puella The azure damselfly is a slender sky-blue damselfly with black markings, one of the most abundant damselflies of ponds and ditches, told from its relatives by a black U-shaped mark. Read the guide →
Birds LC Azure Kingfisher Ceyx azureus The azure kingfisher flashes along quiet Australian forest streams like a living jewel, its deep blue back and orange underparts visible only in a brief blur before it vanishes back into the shadows. Read the guide →
Mammals LC Baboon Papio A baboon is a large, ground-living African monkey with a dog-like muzzle that lives in big troops with complex politics, and it is a bold crop raider that thrives alongside people. Read the guide →
Invertebrates LC Backswimmer Notonectidae A backswimmer is a predatory water bug that rows through ponds upside down just below the surface, hunting insects, tadpoles, and small fish, and gives a burning bite if handled. Read the guide →
Mammals CR Baiji Lipotes vexillifer The baiji was declared functionally extinct after a 2006 survey found no individuals, a once-thriving Yangtze dolphin whose disappearance is one of the starkest modern conservation losses. Read the guide →
Birds LC Baillon's Crake Zapornia pusilla Baillon's crake ranks among the smallest rails on Earth, a tiny reed-bed specialist found across an enormous range spanning Europe, Africa, Asia, and Australia yet rarely glimpsed anywhere within it. Read the guide →
Mammals LC Baird's Beaked Whale Berardius bairdii Baird's beaked whale is the largest of all beaked whale species, a deep-diving North Pacific specialist that travels in tight social groups and has been targeted by commercial whaling in Japan. Read the guide →
Reptiles LC Baird's Rat Snake Pantherophis bairdi Baird's rat snake is confined to the rugged canyon country of the Trans-Pecos region, an excellent climber with a striking orange-to-gray gradient along its body. Read the guide →
Mammals EN Baird's Tapir Tapirus bairdii Baird's tapir is the largest land mammal of Central America, an Endangered swimmer and seed disperser of tropical forests and wetlands from southern Mexico to northern Colombia. Read the guide →
Reptiles DD Baja California Legless Lizard Anniella geronimensis The Baja California legless lizard moves through loose sand almost like swimming, and unlike a snake it can still blink, thanks to functional eyelids most people never think to check for. Read the guide →
Reptiles LC Baja California Ratsnake Bogertophis rosaliae The Baja California ratsnake survives on a peninsula so dry that most rodent-eating snakes could never make a living there, relying on scattered desert oases most other reptiles pass by entirely. Read the guide →
Birds LC Bald Eagle Haliaeetus leucocephalus The bald eagle is a fish-hunting sea eagle and a rare conservation success — back from near-extinction in the US. Learn about its huge nests, its eyesight, and why it isn't actually bald. Read the guide →
Fish LC Bald Notothen Pagothenia borchgrevinki The bald notothen lives permanently in the underside of the Antarctic sea ice, using natural antifreeze proteins to survive in water cold enough to freeze most other fish solid. Read the guide →
Mammals VU Bald Uakari Cacajao calvus The bald uakari's bright red bald face signals good health to potential mates, since illness and parasites cause the skin to fade to a duller shade. Read the guide →
Invertebrates LC Bald-Faced Hornet Dolichovespula maculata The bald-faced hornet is not a true hornet at all, but a large, aggressive yellowjacket relative that builds a fully enclosed paper nest and can spray venom toward a threat's eyes. Read the guide →
Reptiles NT Ball Python Python regius The ball python is a small, shy West African constrictor that curls into a ball when frightened. It is the world's most popular pet snake, bred into thousands of colour morphs. Read the guide →
Fish LC Ballan Wrasse Labrus bergylta The ballan wrasse is the largest wrasse of north-eastern Atlantic rocky shores, a thick-lipped, long-lived, colour-variable fish that crushes shellfish and changes sex from female to male. Read the guide →
Invertebrates LC Baltimore Checkerspot Euphydryas phaeton The Baltimore checkerspot depends heavily on turtlehead, a wetland plant, for its caterpillars to survive their first winter huddled together in a communal silk web spun onto the host plant. Read the guide →
Birds LC Baltimore Oriole Icterus galbula The Baltimore oriole is a flame-orange songbird of eastern North America that weaves a hanging pouch nest and comes to backyard feeders for orange halves and grape jelly. Read the guide →
Birds LC Band-tailed Sierra-finch Phrygilus alaudinus The band-tailed sierra-finch ranges across a far broader stretch of the Andes than its Patagonian relative, identified by a distinctive pale band crossing its tail feathers. Read the guide →
Birds LC Band-winged Nightjar Systellura longirostris The band-winged nightjar hunts insects at dusk across high Andean grassland, identified in flight by a pale band crossing each wing. Read the guide →
Invertebrates LC Banded Coral Shrimp Stenopus hispidus The banded coral shrimp runs a cleaning station in a fixed reef territory, waving long white antennae to advertise its services to fish willing to hold still for a scrub. Read the guide →
Fish LC Banded Darter Etheostoma zonale The banded darter grazes algae directly off submerged rocks in fast-flowing riffles, an unusual feeding habit among darters that sets it apart from most of its strictly invertebrate-hunting relatives. Read the guide →
Invertebrates LC Banded Demoiselle Calopteryx splendens The banded demoiselle is a metallic blue damselfly of slow rivers whose male has a broad dark band across each wing and flutters through the air like a butterfly. Read the guide →
Reptiles LC Banded Gecko Coleonyx variegatus The banded gecko has movable eyelids unlike most other gecko species, a small desert lizard that blinks normally while its close relatives instead lick their permanently exposed eyes clean. Read the guide →
Mammals EN Banded Hare-Wallaby Lagostrophus fasciatus The banded hare-wallaby is the last living member of its entire subfamily, surviving naturally only on two small islands off the coast of Western Australia. Read the guide →
Fish LC Banded Killifish Fundulus diaphanus The banded killifish forms large, tight schools that swim just beneath the surface of clear, weedy shallows, its narrow vertical bars breaking up the outline of any single fish within the group. Read the guide →
Birds LC Banded Kingfisher Lacedo pulchella The banded kingfisher shows an unusually large difference between males and females, a blue-and-black banded male paired with a rufous, black-barred female. Read the guide →
Reptiles LC Banded Krait Bungarus fasciatus The banded krait is a boldly striped black-and-yellow snake of South and Southeast Asia that hunts other snakes at night, with a deadly neurotoxic venom but a placid nature by day. Read the guide →
Mammals LC Banded Linsang Prionodon linsang The banded linsang is believed to be one of the closest living relatives of true cats despite looking almost exactly like a civet, an extremely agile Southeast Asian tree climber. Read the guide →
Mammals LC Banded Mongoose Mungos mungo The banded mongoose lives in tight packs that raise pups communally, mob predators together, and even kill cobras. All the females in a group give birth on the same night. Read the guide →
Amphibians LC Banded Newt Ommatotriton A banded newt is a small Middle Eastern newt whose breeding male grows a tall, smooth-edged crest and a striking blue-and-white-striped tail, unlike the jagged crest of most other crested newts. Read the guide →
Fish LC Banded Pygmy Sunfish Elassoma zonatum The banded pygmy sunfish rarely grows longer than an inch and a half, a tiny predator of vegetation-choked swamps and ditches that spends its entire life hidden among dense aquatic plants. Read the guide →
Fish LC Banded Sculpin Cottus carolinae The banded sculpin favours cool spring-fed streams and cave-adjacent waters of the Ozark and Appalachian highlands, its dark banding blending into the same gravel it hides against. Read the guide →
Fish LC Banded Sunfish Enneacanthus obesus The banded sunfish shares its acidic blackwater habitat with the more boldly patterned blackbanded sunfish, wearing a softer, more diffuse version of the same vertical striping. Read the guide →
Fish EN Banggai Cardinalfish Pterapogon kauderni The Banggai cardinalfish is found naturally only around a small group of Indonesian islands, with males carrying developing eggs and young in their mouths until the fry can fend for themselves. Read the guide →
Amphibians LC Banjo Frog Limnodynastes A banjo frog is a stout burrowing Australian frog whose call is a single resonant bonk like a plucked banjo string, and a full chorus of them across a wetland sounds like a band tuning up. Read the guide →
Mammals LC Bank Vole Myodes glareolus The bank vole is a key food source for owls and foxes across European woodland, though it also carries a hantavirus that can occasionally spread to people. Read the guide →
Mammals LC Banner-tailed Kangaroo Rat Dipodomys spectabilis The banner-tailed kangaroo rat builds large dirt mounds in the southwestern desert and thumps its hind feet in rhythmic drumming patterns to send messages through the ground. Read the guide →
Fish LC Bantam Sunfish Lepomis symmetricus The bantam sunfish is one of the least commonly seen members of its genus, confined to swampy Mississippi River floodplain backwaters that most anglers rarely fish. Read the guide →
Birds NT Bar-tailed Godwit Limosa lapponica The bar-tailed godwit makes the longest non-stop flight of any bird — tracked from Alaska to New Zealand across the open Pacific in about 11 days without landing, resting, or feeding once. Read the guide →
Mammals VU Barasingha Rucervus duvaucelii The barasingha takes its name from antlers that can carry twelve or more points, an Indian swamp deer brought back from the edge of extinction through decades of protection. Read the guide →
Fish LC Barb Puntius and relatives A barb is a small, active, schooling cyprinid fish of Africa and Asia named for its mouth barbels, a community aquarium mainstay that needs a proper school to keep its fin-nipping in check. Read the guide →
Reptiles CR Barbados Threadsnake Tetracheilostoma carlae The Barbados threadsnake is the smallest known snake in the world, about as long and thin as a strand of spaghetti. It burrows in soil, eats ant and termite larvae, and lays a single large egg. Read the guide →
Mammals EN Barbary Macaque Macaca sylvanus The Barbary macaque is the only primate living wild in Europe, its Gibraltar population surviving centuries as the sole non-human primate on the continent. Read the guide →
Birds LC Barbary Partridge Alectoris barbara The Barbary partridge wears a distinctive chestnut collar across the upper breast, setting it apart from its barred-flanked North African and southern European Alectoris relatives. Read the guide →
Mammals NT Barbastelle Barbastella barbastellus The barbastelle is a dark, pug-faced woodland bat that hunts moths with very quiet calls, a stealthy approach that helps it avoid being heard by its prey. Read the guide →
Fish LC Barbel Barbus barbus The barbel is a powerful, torpedo-shaped river fish of fast, gravelly water, with four whisker-like barbels around its mouth that it uses to find food on the bottom, and a poisonous roe. Read the guide →
Birds LC Barbet Lybiidae, Megalaimidae, Capitonidae The barbet excavates its own tree-cavity nest like a woodpecker, then defends it with a loud, relentlessly repeated call, some species even duetting in tight synchrony. Read the guide →
Birds LC Bare-faced Ibis Phimosus infuscatus The bare-faced ibis probes damp South American grassland and wetland soil with a curved bill, its reddish facial skin visible from a distance against dark plumage. Read the guide →
Birds VU Bare-necked Umbrellabird Cephalopterus glabricollis The bare-necked umbrellabird carries a crest that overhangs its bill like an umbrella, along with an inflatable bare throat wattle used in display. Read the guide →
Reptiles LC Bark Anole Anolis distichus The bark anole spends most of its life on tree trunks rather than leaves or twigs, its mottled grey-brown pattern blending so well with bark that it can be nearly impossible to spot until it moves. Read the guide →
Amphibians LC Barking Frog Craugastor augusti The barking frog is a dog-voiced, rock-dwelling amphibian that skips the tadpole stage entirely, laying eggs on land that hatch directly into fully formed froglets. Read the guide →
Amphibians LC Barking Tree Frog Dryophytes gratiosus The barking tree frog is the largest tree frog native to the US, a plump spotted climber of southern pinewoods that barks like a dog from the treetops and digs into sand in dry spells. Read the guide →
Birds LC Barn Owl Tyto alba The barn owl hunts in total darkness by sound alone, guided by its heart-shaped face and lopsided ears. Learn how its silent flight works and why farmers put up nest boxes for it. Read the guide →
Birds LC Barn Swallow Hirundo rustica The barn swallow is the most widespread swallow on Earth, a steel-blue bird with a deeply forked tail that catches insects on the wing and builds its mud-cup nest inside barns and under bridges. Read the guide →
Invertebrates NE Barnacle Cirripedia A barnacle is a crustacean that glues its own head to a rock for life, then lies on its back raking food in with feathery legs, and it has the longest penis relative to body size of any animal. Read the guide →
Fish NE Barracuda Sphyraena A barracuda is a long, silver, torpedo-shaped ocean predator with a jutting jaw of fang-like teeth that ambushes fish in an explosive burst; the great barracuda grows longer than a person. Read the guide →
Fish LC Barramundi Lates calcarifer A barramundi is a fish of Indo-Pacific rivers and estuaries that migrates between fresh and salt water, starts life as a male and later turns female, and is a prized Australian sport and food fish. Read the guide →
Birds LC Barred Antshrike Thamnophilus doliatus The barred antshrike raises a shaggy crest and flicks its tail when alarmed, one of the most common and widely tolerant antshrike species in the Americas. Read the guide →
Birds LC Barred Owl Strix varia The barred owl's expansion into the Pacific Northwest has put it in direct competition with the threatened northern spotted owl, turning one owl's success into another's crisis. Read the guide →
Amphibians LC Barred Tiger Salamander Ambystoma mavortium The barred tiger salamander is the largest terrestrial salamander in North America, a burrowing amphibian bold enough to eat other salamanders and even small snakes when the chance arises. Read the guide →
Invertebrates NE Barrel Jellyfish Rhizostoma pulmo The barrel jellyfish is one of the largest jellyfish of north-eastern Atlantic coasts, a dome-shaped, tentacle-less giant with frilly oral arms and a mild sting that shelters young fish. Read the guide →
Invertebrates DD Barrel Sponge Xestospongia muta The barrel sponge grows large enough for a diver to fit inside, and some individuals are believed to have lived for well over a thousand years, among the oldest animals on the reef. Read the guide →
Fish NE Barreleye Macropinna microstoma The barreleye is a small deep-sea fish with a transparent, fluid-filled dome for a forehead. Its tubular green eyes sit inside the dome and rotate to look straight up through the fish's own head. Read the guide →
Amphibians CR Barton Springs Salamander Eurycea sosorum The Barton Springs salamander exists nowhere on Earth except one spring complex in the middle of Austin, Texas, making its entire global population dependent on one urban waterway. Read the guide →
Reptiles LC Basilisk Lizard Basiliscus A basilisk lizard is a crested Central American lizard that escapes by sprinting across open water on its hind legs, staying up for several metres before it sinks and swims. Read the guide →
Invertebrates LC Basket Star Gorgonocephalus A basket star unfurls arms that branch dozens of times into a dense, tangled net, transforming from a tightly curled ball by day into a filter-feeding basket spread against the current by night. Read the guide →
Fish EN Basking Shark Cetorhinus maximus The basking shark is the second-largest fish alive — a 7-to-8-metre plankton strainer that swims with its metre-wide mouth open, filtering 2,000 tonnes of water an hour, and gathers in mysterious. Read the guide →
Fish NE Bass Micropterus, Morone, and others A bass is any of many unrelated spiny-finned fish that share the name, from the freshwater largemouth bass, the top sport fish in North America, to striped bass, sea bass, and the invasive Nile perch. Read the guide →
Mammals NE Bat Chiroptera A bat is the only mammal that truly flies, using a wing of skin stretched over long finger bones, and most bats navigate and hunt in total darkness by shouting and listening to the echoes. Read the guide →
Mammals LC Bat-eared Fox Otocyon megalotis The bat-eared fox uses enormous ears to hear insects moving underground, an unusual termite-eating canid with more teeth than any other fox or dog. Read the guide →
Birds EN Bateleur Terathopius ecaudatus The bateleur has such a short tail that it can barely perch normally, spending nearly its entire life airborne instead, rocking side to side in flight like a tightrope walker balancing overhead. Read the guide →
Fish LC Batfish Ogcocephalidae The batfish walks across the seafloor on leg-like fins instead of swimming, luring prey close with a built-in fishing rod on its snout before snapping it up with barely a movement. Read the guide →
Invertebrates NE Bath Sponge Spongia officinalis The bath sponge is a dark, lumpy Mediterranean sponge with a soft, elastic skeleton of spongin fibres that divers have harvested for washing since ancient times, and which disease has devastated. Read the guide →
Mammals EN Bay Cat Catopuma badia The bay cat is a small, reddish-brown cat found only on the island of Borneo, one of the least known and most rarely photographed wild cats in the world. Read the guide →
Birds LC Bay-Headed Tanager Tangara gyrola The bay-headed tanager pairs a rich chestnut head with a green body and blue underparts, one more vivid face within the sprawling Tangara genus. Read the guide →
Invertebrates NE Beadlet Anemone Actinia equina The beadlet anemone is the red jelly blob of European rock pools, a small anemone ringed with blue beads that it uses as weapons against rival anemones, and that gives birth to live young. Read the guide →
Mammals NE Bear Ursidae A bear is a large, heavily built mammal that walks on the soles of its feet, and most bears are opportunistic omnivores that spend the warm months building fat for a winter of dormancy in a den. Read the guide →
Reptiles LC Bearded Dragon Pogona A bearded dragon is a calm Australian lizard, the world's top pet lizard, that flares a black throat when threatened, waves an arm in submission, and can be sex-reversed by incubation heat. Read the guide →
Mammals LC Bearded Seal Erignathus barbatus The bearded seal uses extraordinarily long, dense facial whiskers to feel for prey in soft sediment, the largest Arctic seal species and a food source for polar bears alongside the ringed seal. Read the guide →
Birds NT Bearded Vulture Gypaetus barbatus The bearded vulture lives almost entirely on bone. It carries large bones high into the air and drops them onto rock to shatter them, then swallows the fragments, which its stomach acid dissolves. Read the guide →
Invertebrates LC Beautiful Demoiselle Calopteryx virgo The beautiful demoiselle is a damselfly of fast, clean streams whose male has deep violet-blue wings and body, and whose presence is a sign of good water quality. Read the guide →
Mammals LC Beaver Castor A beaver is a large, dam-building rodent that reshapes whole river valleys, felling trees with self-sharpening orange teeth and flooding land to make the deep pond it needs to stay safe. Read the guide →
Mammals NT Bechstein's Bat Myotis bechsteinii Bechstein's bat is a rare, long-eared woodland bat that depends on old broadleaved forest with tree holes and gleans insects from leaves and the ground. Read the guide →
Invertebrates NE Bedbug Cimex lectularius A bedbug is a small, flat, wingless insect that hides in mattresses and furniture by day and comes out at night to drink human blood, and after decades of near-absence it has surged back worldwide. Read the guide →
Invertebrates NE Bee Anthophila A bee is a wasp that turned vegetarian, feeding itself and its young on pollen and nectar, and in doing so became the most important pollinator of wild plants and crops on Earth. Read the guide →
Birds NT Bee Hummingbird Mellisuga helenae The bee hummingbird of Cuba is the smallest bird in the world — about 5.5 cm and 2 grams, lighter than a penny. Its heart beats up to 1,200 times a minute and its wings hum at 80 beats a second. Read the guide →
Birds LC Bee-eater Meropidae A bee-eater catches bees and wasps in mid-flight, then rubs the insect against a perch to squeeze out its venom and remove the stinger before eating it, a routine practised with remarkable precision. Read the guide →
Invertebrates NE Bee-fly Bombylius major The bee-fly is a furry, bumblebee-like spring fly with a long rigid snout that hovers at primroses and violets, and whose larvae parasitise the nests of solitary mining bees. Read the guide →
Invertebrates NE Bee-wolf Philanthus triangulum The bee-wolf is a yellow-and-black digger wasp that hunts honeybees, paralyses them with its sting, and carries them to a sandy burrow to feed its larvae, and which is expanding across Britain. Read the guide →
Invertebrates NE Beetle Coleoptera A beetle is an insect with its front wings hardened into a case over its back, a design so durable that around one in every four named animal species on Earth is a kind of beetle. Read the guide →
Mammals VU Beira Dorcatragus megalotis The beira is the sole member of its genus, a tiny, large-eared antelope that bounds across the steep, rocky mountains of the Horn of Africa with a build similar to the klipspringer. Read the guide →
Birds LC Bell's Vireo Vireo bellii One subspecies of Bell's vireo declined so severely from habitat loss and cowbird parasitism that it was listed as federally endangered, while other subspecies of the species remain common elsewhere. Read the guide →
Birds LC Belted Kingfisher Megaceryle alcyon The belted kingfisher patrols North American rivers with a loud rattle, dives headfirst for fish, nests in a tunnel in an earth bank, and has a female more colourful than the male. Read the guide →
Fish CR Beluga Sturgeon Huso huso The beluga sturgeon is the largest fish that runs up rivers to breed — historically over 7 metres — and the source of the most expensive caviar on Earth. Wild populations have nearly vanished. Read the guide →
Mammals LC Beluga Whale Delphinapterus leucas The beluga is a small white Arctic whale with a flexible neck, a squishy forehead it can reshape, and a vocal range so wide that whalers called it the "sea canary." Read the guide →
Reptiles LC Bengal Monitor Varanus bengalensis The Bengal monitor is a large, widespread lizard of South Asia that forages in forests, farmland, and village edges, and is protected under international trade law because it has been heavily hunted. Read the guide →
Reptiles LC Berber Skink Eumeces algeriensis The Berber skink is one of the largest skink species in North Africa, a heavily built, glossy lizard that forages openly for both plants and animal prey across semi-arid scrubland. Read the guide →
Invertebrates LC Beroe Beroe Beroe has no tentacles at all, instead swimming with its huge mouth open and engulfing other comb jellies whole, gripping them with rows of stiffened cilia that work like teeth. Read the guide →
Amphibians EN Berry Cave Salamander Gyrinophilus gulolineatus The Berry Cave salamander lives entirely within a handful of Tennessee cave systems, keeping its larval gills and reduced eyes into adulthood in permanent underground darkness. Read the guide →
Invertebrates LC Bess Beetle Passalidae The bess beetle lives in family colonies inside rotting logs, pre-chewing wood for its own larvae and communicating with them through a surprisingly varied vocabulary of squeaks. Read the guide →
Mammals LC Bharal Pseudois nayaur The bharal sits taxonomically between true sheep and goats, a blue-grey Himalayan specialist that ranks as the primary prey of the elusive snow leopard. Read the guide →
Fish LC Bichir Polypterus The bichir is an ancient African fish with a row of finlets down its back, thick armour scales, a pair of true lungs, and stout fins it can walk on across land between pools. Read the guide →
Fish LC Bicolor Blenny Ecsenius bicolor The bicolor blenny splits its body neatly into two zones, a dark front half and a warm orange rear half, darting from a small burrow to graze algae before retreating again. Read the guide →
Birds LC Bicolored Antbird Gymnopithys bicolor The bicolored antbird depends entirely on army ant swarms for food, following the ants to catch insects they flush rather than eating the ants themselves. Read the guide →
Mammals LC Big Brown Bat Eptesicus fuscus The big brown bat has proven far more resistant to white-nose syndrome than many smaller bat relatives, a hardy, adaptable insect hunter equally at home roosting in a cave, an attic, or a hollow tree. Read the guide →
Mammals LC Big-eared Woolly Bat Chrotopterus auritus The big-eared woolly bat is one of the largest carnivorous bats of the Americas, a woolly-coated predator of rodents, birds, lizards, and other bats that roosts in caves and hollow trees. Read the guide →
Reptiles CR Big-headed Turtle Platysternon megacephalum The big-headed turtle of Asian mountain streams has a head too big to pull into its shell, so it is armoured instead, and the turtle climbs rocks and trees using its long tail as a brace. Read the guide →
Fish LC Bigeye Shiner Notropis boops The bigeye shiner has unusually large eyes for a small minnow, an adaptation that lets it feed effectively in clear water even during the dim light of dawn and dusk. Read the guide →
Invertebrates NE Bigfin Squid Magnapinna The bigfin squid trails ten arms of nearly equal length, each bent at a sharp right angle partway along, drifting through the deep sea in a posture unlike any other known cephalopod. Read the guide →
Fish LC Bighead Carp Hypophthalmichthys nobilis The bighead carp filters plankton from the water using an enormous mouth, growing large enough and spreading fast enough since its introduction to threaten the food supply of native fish. Read the guide →
Mammals LC Bighorn Sheep Ovis canadensis The bighorn sheep's massive curled horns can weigh more than all the bones in its body combined, weight males slam together in head-butting contests to establish dominance on steep mountain terrain. Read the guide →
Fish LC Bigmouth Buffalo Ictiobus cyprinellus The bigmouth buffalo is North America's largest sucker, often mistaken for a carp, and a fish that turned out to live longer than any other, with some individuals over 110 years old. Read the guide →
Mammals VU Binturong Arctictis binturong The binturong is a shaggy Southeast Asian tree-dweller with a fully prehensile tail and urine that smells like buttered popcorn. It is a key disperser of strangler fig seeds and is now Vulnerable. Read the guide →
Birds LC Bird-of-paradise Paradisaeidae A bird-of-paradise is a New Guinea forest bird in which generations of female choice have produced the most extravagant plumes, colours, and courtship dances of any bird. Read the guide →
Amphibians LC Bird-Voiced Treefrog Hyla avivoca The bird-voiced treefrog produces a whistling call so bird-like that it regularly fools observers into scanning the trees above rather than the swamp water below where the frog is actually calling. Read the guide →
Mammals CR Black Bearded Saki Chiropotes satanas The black bearded saki is a Critically Endangered Amazonian monkey with a thick black beard and powerful jaws that crack open hard seeds, found in the shrinking forests of eastern Brazil. Read the guide →
Fish LC Black Bullhead Ameiurus melas The black bullhead tolerates water so poor in oxygen that most other fish would suffocate, and its young form a tight, parent-guarded schooling ball. Read the guide →
Reptiles LC Black Caiman Melanosuchus niger The black caiman is the Amazon's largest predator, reaching 5 metres, its dark skin aiding warmth and night camouflage. Hunted almost to extinction for its hide by the 1970s, it has recovered. Read the guide →
Invertebrates LC Black Coral Antipatharia The black coral is named not for the colour of its living tissue but for its dark, thorn-covered skeleton, some colonies estimated to be among the oldest living animals on Earth. Read the guide →
Fish LC Black Crappie Pomoxis nigromaculatus The black crappie carries irregular black speckling rather than the vertical bars of its close relative, and its extra dorsal spines are the most reliable way to tell the two apart. Read the guide →
Fish LC Black Dragonfish Idiacanthus atlanticus The black dragonfish produces one of the only red lights in the deep sea, an invisible beam most prey cannot see, letting it hunt like a sniper using night-vision no other predator shares. Read the guide →
Fish LC Black Drum Pogonias cromis The black drum produces its own drumming sound by vibrating muscles against its swim bladder, then crushes oysters and crabs whole with powerful plate-like teeth in its throat. Read the guide →
Mammals LC Black Flying Fox Pteropus alecto The black flying fox is a large, russet-collared fruit bat of northern Australia, New Guinea, and Indonesia that forms noisy camps, pollinates eucalypts, and is a natural host of Hendra virus. Read the guide →
Fish NE Black Ghost Knifefish Apteronotus albifrons The black ghost knifefish swims entirely backward and forward with a single rippling fin, generating a weak electric field around its body to navigate and hunt in total darkness. Read the guide →
Fish NT Black Grouper Mycteroperca bonaci The black grouper grows large and powerful enough to become one of the most sought-after trophy catches on Caribbean and Gulf reefs, a dark, heavily built ambush predator. Read the guide →
Birds LC Black Hawk-eagle Spizaetus tyrannus The black hawk-eagle ranges across Neotropical forest from Mexico to Argentina, a mostly black raptor with a banded tail and a sharp, piercing call. Read the guide →
Birds LC Black Heron Egretta ardesiaca The black heron hunts by forming its wings into an umbrella-like canopy over the water, a highly unusual behaviour that creates shade to help it spot fish hiding beneath. Read the guide →
Mammals LC Black Howler Monkey Alouatta caraya Male and female black howler monkeys look like two different species entirely, the males solid black and the females a striking golden-blonde. Read the guide →
Mammals EN Black Lion Tamarin Leontopithecus chrysopygus The black lion tamarin is an Endangered Brazilian monkey with a jet-black coat and a golden rump, confined to a few fragments of Atlantic forest in the state of Sao Paulo. Read the guide →
Reptiles LC Black Mamba Dendroaspis polylepis The black mamba is Africa's most feared snake — long, fast, and armed with a fast-acting neurotoxic venom. Learn where the name comes from, how dangerous it really is, and why it usually flees. Read the guide →
Fish DD Black Marlin Istiompax indica The black marlin is one of the fastest fish in the ocean, propelled by rigid, fixed pectoral fins that cannot be folded flat against the body the way most other billfish can manage. Read the guide →
Amphibians LC Black Mountain Salamander Desmognathus welteri The black mountain salamander shares its Appalachian range with several similar dusky salamander relatives, making genetics and precise location more reliable for identification than appearance. Read the guide →
Birds VU Black Petrel Procellaria parkinsoni The black petrel breeds only on two small New Zealand islands, nesting in burrows dug high on forested peaks and facing significant mortality from longline fishing across its wide foraging range. Read the guide →
Birds LC Black Phoebe Sayornis nigricans The black phoebe rarely strays more than a few feet from water, perching low over streams and ponds to sally out after flying insects before returning to the exact same favoured perch again and again. Read the guide →
Birds NT Black Rail Laterallus jamaicensis The black rail is the smallest rail in North America, a sparrow-sized marsh bird so secretive that most of what is known about it comes from its distinctive nighttime calls. Read the guide →
Amphibians LC Black Rain Frog Breviceps fuscus The black rain frog is a round, perpetually grumpy-looking burrowing frog from South Africa's southern mountains. It cannot hop or swim, and puffs itself into a hard ball when threatened. Read the guide →
Fish LC Black Redhorse Moxostoma duquesnei The black redhorse requires cleaner, faster-flowing water than most of its redhorse relatives, making it one of the more reliable indicators of good stream health within its range. Read the guide →
Invertebrates LC Black Saddlebags Tramea lacerata The black saddlebags carries a bold dark patch at the base of each hindwing, like saddlebags slung over a horse, and travels farther and faster than almost any other dragonfly in North America. Read the guide →
Amphibians LC Black Salamander Aneides flavipunctatus The black salamander is a dark, secretive lungless salamander from the Pacific coast that can climb using a semi-prehensile tail and defends its territory with genuine, sometimes injurious bites. Read the guide →
Fish LC Black Scorpionfish Scorpaena porcus The black scorpionfish is a mottled, spiny, perfectly camouflaged ambush predator of rocky Mediterranean and Black Sea shores whose venomous dorsal spines give a painful sting. Read the guide →
Fish LC Black Seabream Spondyliosoma cantharus The black seabream is a dark, deep-bodied, shoaling fish of reefs and wrecks in the north-eastern Atlantic whose male clears a nest in the sand, turns blue-black, and guards the eggs. Read the guide →
Birds NT Black Skimmer Rynchops niger The black skimmer's lower bill is longer than its upper one, a feature found in no other North American bird, sliced through the water's surface to catch fish by touch alone. Read the guide →
Mammals VU Black Spider Monkey Ateles paniscus The black spider monkey has no thumbs at all, relying instead on long hook-like fingers and a fingerprint-patterned tail tip for its grip through the canopy. Read the guide →
Reptiles LC Black Spiny-tailed Iguana Ctenosaura similis The black spiny-tailed iguana holds the record for the fastest recorded lizard sprint on Earth, and its heavily spined tail can deliver a surprisingly forceful strike when threatened. Read the guide →
Fish LC Black Swallower Chiasmodon niger The black swallower can eat prey many times its own body weight in a single meal, a small deep-sea fish with a stomach so expandable it sometimes overestimates what it can handle. Read the guide →
Invertebrates LC Black Swallowtail Papilio polyxenes The black swallowtail caterpillar extends a bright orange, forked organ from behind its head when threatened, releasing a foul smell strong enough to deter birds and other predators. Read the guide →
Birds LC Black Tern Chlidonias niger The black tern breaks the usual seabird mould, breeding on freshwater marshes far from any coast and wearing an almost entirely black breeding plumage unlike beach-dwelling terns. Read the guide →
Amphibians VU Black Toad Anaxyrus exsul The black toad exists nowhere on Earth except one isolated desert valley in California, one of the narrowest ranges of any vertebrate, its whole population tied to a handful of springs. Read the guide →
Reptiles NT Black Tree Monitor Varanus beccarii The black tree monitor turns almost entirely black as it matures, an arboreal Indonesian lizard with a prehensile tail that spends nearly its whole life gripping branches high above the forest floor. Read the guide →
Mammals NT Black Wallaroo Osphranter bernardus The black wallaroo is confined to a small, rugged stretch of rocky escarpment in Arnhem Land, the smallest and least studied member of the wallaroo group. Read the guide →
Amphibians EN Black Warrior Waterdog Necturus alabamensis The Black Warrior waterdog survives only in one Alabama river already altered by dams and pollution, one of the more critically endangered aquatic salamanders in North America. Read the guide →
Invertebrates LC Black Widow Spider Latrodectus mactans The black widow's venom is about 15 times stronger than a rattlesnake's, drop for drop, but she injects so little that healthy adults almost always survive. The red hourglass is a warning. Read the guide →
Mammals LC Black Wildebeest Connochaetes gnou The black wildebeest was hunted to the edge of extinction during the nineteenth century, a smaller, darker relative of the blue wildebeest saved through protection on private land. Read the guide →
Invertebrates LC Black Witch Moth Ascalapha odorata The black witch moth is one of the largest moths in North America and can turn up thousands of miles from home after being swept north on storm winds. Read the guide →
Birds LC Black Woodpecker Dryocopus martius The black woodpecker is the largest woodpecker in Europe, carving out nest holes so large that they later become homes for owls, martens, and other animals unable to make cavities of their own. Read the guide →
Birds EN Black-and-chestnut Eagle Spizaetus isidori The black-and-chestnut eagle hunts through Andean cloud forest, one of the rarest and least-studied eagles in the Americas, requiring vast, undisturbed territories to survive. Read the guide →
Mammals NT Black-And-Rufous Elephant Shrew Rhynchocyon petersi The black-and-rufous elephant shrew splits its body into two bold colours, black in front giving way sharply to deep rufous-red behind, a striking pattern found in coastal East African forest. Read the guide →
Mammals LC Black-and-White Colobus Colobus guereza The black-and-white colobus has a cow-like multi-chambered stomach for digesting tough leaves, and newborns are born pure white before darkening with age. Read the guide →
Birds LC Black-and-white Owl Ciccaba nigrolineata The black-and-white owl hunts bats and large insects through Neotropical forest at night, identified by bold black-and-white barring across its entire body. Read the guide →
Mammals CR Black-and-White Ruffed Lemur Varecia variegata The black-and-white ruffed lemur gives birth to litters of up to six young at once, then parks them in a nest rather than carrying them like most other primates. Read the guide →
Birds LC Black-and-White Warbler Mniotilta varia The black-and-white warbler forages like a nuthatch, creeping headfirst down tree trunks and along branches to probe bark crevices, a foraging style unlike almost any other North American warbler. Read the guide →
Amphibians LC Black-bellied Salamander Desmognathus quadramaculatus The black-bellied salamander is the biggest Appalachian stream salamander, a heavy, aggressive lungless hunter that takes insects, crayfish, and even other salamanders in fast mountain water. Read the guide →
Amphibians LC Black-Bellied Slender Salamander Batrachoseps nigriventris The black-bellied slender salamander squeezes through gaps barely wider than its own head, its thread-thin body suited to a life spent almost entirely underground. Read the guide →
Birds LC Black-bellied Storm-petrel Fregetta tropica The black-bellied storm-petrel is one of the largest of the storm-petrels, marked by a dark stripe down its belly, and forages far from land, often near the edge of the Antarctic sea ice. Read the guide →
Birds LC Black-browed Albatross Thalassarche melanophris The black-browed albatross has a dark streak of feathers around each eye resembling an angry eyebrow, and is the most widespread and numerous of the smaller albatross species called mollymawks. Read the guide →
Birds LC Black-chested Buzzard-eagle Geranoaetus melanoleucus The black-chested buzzard-eagle is one of the largest birds of prey in South America, soaring over open Andean and Patagonian terrain in search of rabbits, rodents, and other mammals. Read the guide →
Birds LC Black-Chinned Hummingbird Archilochus alexandri The black-chinned hummingbird's throat looks plain black in most light, but at the right angle a thin iridescent purple band flashes along its lower edge, then vanishes. Read the guide →
Birds LC Black-chinned Siskin Spinus barbatus The black-chinned siskin forms conspicuous flocks across southern beech forest and garden alike, males marked by a distinctive black patch beneath the bill that gives the species its name. Read the guide →
Birds LC Black-collared Barbet Lybius torquatus A pair of black-collared barbets calls in such tightly timed alternation that the two voices can sound to a human ear like a single bird calling. Read the guide →
Birds LC Black-crowned Night-Heron Nycticorax nycticorax The black-crowned night-heron is one of the most widespread herons in the world, a stocky, red-eyed hunter that does most of its feeding after dark while other herons sleep. Read the guide →
Birds LC Black-crowned Tityra Tityra inquisitor The black-crowned tityra shows a solid black crown against pale grey-white body plumage, a quieter relative of the masked tityra found across a broader stretch of the Neotropics. Read the guide →
Birds LC Black-Faced Antthrush Formicarius analis The black-faced antthrush walks upright with its tail cocked like a tiny chicken, flipping leaf litter on the forest floor in search of hidden insects. Read the guide →
Birds LC Black-faced Ibis Theristicus melanopis The black-faced ibis forages across high-altitude Andean grassland and lowland Patagonian pasture alike, probing soil for worms and insects with the same curved bill as its close relative. Read the guide →
Birds NT Black-faced Sheathbill Chionis minor The black-faced sheathbill has bare, dark, warty facial skin, setting it apart from its all-white relative the snowy sheathbill, and scavenges around sub-Antarctic seabird and seal colonies. Read the guide →
Birds NT Black-footed Albatross Phoebastria nigripes The black-footed albatross is the darkest of the North Pacific albatross species, feeding heavily at night on squid and fish eggs that rise toward the surface after dark. Read the guide →
Mammals VU Black-footed Cat Felis nigripes The black-footed cat is Africa's smallest cat and, by hunt success, the deadliest of all cats — it makes a kill roughly every 50 minutes through the night. Read the guide →
Mammals EN Black-Footed Ferret Mustela nigripes The black-footed ferret was declared extinct in the wild in 1987 before one surviving colony made a captive breeding recovery possible, a prairie dog specialist tied directly to prairie dog towns. Read the guide →
Mammals VU Black-Footed Rock-Wallaby Petrogale lateralis The black-footed rock-wallaby shelters among sun-baked desert boulders, its genetically distinct populations scattered across isolated rocky outcrops of arid Australia. Read the guide →
Birds LC Black-headed Duck Heteronetta atricapilla The black-headed duck is the only duck species known to be an obligate brood parasite, laying every egg in the nests of other birds and never raising its own young. Read the guide →
Birds LC Black-headed Gull Chroicocephalus ridibundus Despite its name, the black-headed gull's breeding hood is chocolate-brown rather than true black, and for much of the year it wears a plain white head with a small dark ear spot instead. Read the guide →
Reptiles LC Black-Knobbed Map Turtle Graptemys nigrinoda The black-knobbed map turtle carries a row of raised, dark-tipped knobs along its shell's central ridge, an unusually pronounced feature that makes it one of the more recognisable map turtles. Read the guide →
Birds VU Black-legged Kittiwake Rissa tridactyla The black-legged kittiwake is a true ocean-going gull, spending most of the year far out at sea and returning to land only to nest on narrow cliff ledges, its wingtips looking as if dipped in ink. Read the guide →
Mammals LC Black-Legged Mongoose Bdeogale nigripes The black-legged mongoose carries dark, almost black legs that contrast sharply against its paler body, a poorly studied rainforest species of West and Central Africa. Read the guide →
Reptiles LC Black-Necked Garter Snake Thamnophis cyrtopsis The black-necked garter snake carries a pair of dark blotches just behind its head, and it sticks closer to rocky canyon streams than almost any other garter snake in its range. Read the guide →
Reptiles LC Black-necked Spitting Cobra Naja nigricollis The black-necked spitting cobra defends itself by firing two fine jets of venom from its fangs at an attacker's eyes from 3 metres, causing intense pain and, untreated, blindness. It bites too. Read the guide →
Birds LC Black-Necked Stilt Himantopus mexicanus The black-necked stilt wades on the longest legs relative to body size of almost any bird, and a pair defending a nest will fake a broken wing to lure a predator far away from their eggs. Read the guide →
Birds LC Black-necked Swan Cygnus melancoryphus The black-necked swan is South America's only swan species, marked by a striking white body and jet-black neck and head that set it apart from the all-white swans of the Northern Hemisphere. Read the guide →
Amphibians VU Black-Spotted Newt Notophthalmus meridionalis The black-spotted newt often skips the terrestrial eft stage that defines its famous eastern relative, in some populations staying aquatic for essentially its entire life. Read the guide →
Mammals LC Black-Tailed Jackrabbit Lepus californicus The black-tailed jackrabbit sheds excess body heat through enormous, thinly furred ears packed with blood vessels, a desert-adapted hare that relies on speed rather than burrows to escape predators. Read the guide →
Mammals LC Black-Tailed Prairie Dog Cynomys ludovicianus The black-tailed prairie dog lives in sprawling underground towns once home to millions, a highly social burrower whose grazing and digging shape prairie habitat for dozens of other species. Read the guide →
Reptiles LC Black-Tailed Rattlesnake Crotalus molossus The black-tailed rattlesnake is widely considered one of the calmer rattlesnake species, often choosing to sit quietly and rely on camouflage rather than rattling or striking when approached. Read the guide →
Invertebrates LC Black-tailed Skimmer Orthetrum cancellatum The black-tailed skimmer is a dragonfly whose mature male has a powder-blue abdomen ending in a black tip, basking on bare ground beside gravel pits, ponds, and slow rivers. Read the guide →
Birds LC Black-tailed Trogon Trogon melanurus The black-tailed trogon is one of the larger trogon species, males showing a glossy green head and back, a bright yellow bill, and a deep red belly. Read the guide →
Birds LC Black-Throated Blue Warbler Setophaga caerulescens The male and female black-throated blue warbler look so different that early naturalists once classified them as two entirely separate species. Read the guide →
Birds LC Black-throated Huet-huet Pteroptochos castaneus The black-throated huet-huet is a large, ground-dwelling forest bird named for its distinctive repeated call, more often heard echoing through dense undergrowth than seen by observers. Read the guide →
Birds LC Black-Throated Sparrow Amphispiza bilineata The black-throated sparrow can survive almost entirely on the moisture it gets from insects and seeds, sometimes going extended periods in extreme desert heat without ever drinking water directly. Read the guide →
Fish LC Blackbanded Darter Percina nigrofasciata The blackbanded darter is marked with a row of bold, dark, saddle-like blotches along its back, a pattern that helps it disappear against the dappled shade and gravel bottom of its home stream. Read the guide →
Fish NT Blackbanded Sunfish Enneacanthus chaetodon The blackbanded sunfish wears bold vertical black bars over a silvery body, an ornamental pattern striking enough to make it a favorite in the home aquarium trade. Read the guide →
Amphibians LC Blackbelly Salamander Desmognathus quadramaculatus The blackbelly salamander is the largest member of its genus, a powerful predator of fast Appalachian mountain streams that will readily eat smaller salamanders, including its own close relatives. Read the guide →
Birds LC Blackbird Turdus merula and Icteridae A blackbird is really two unrelated birds sharing one name, a European thrush that sings from rooftops and the mostly American Icteridae, glossy birds like the red-winged blackbird. Read the guide →
Mammals LC Blackbuck Antilope cervicapra The blackbuck male darkens to a deep brown-black as he matures, an Indian antelope ranked among the fastest land animals and known for tightly spiralled horns. Read the guide →
Birds LC Blackburnian Warbler Setophaga fusca The male Blackburnian warbler's flame-orange throat glows so brightly against the dark conifer canopy that the species has earned the nickname firethroat. Read the guide →
Birds LC Blackcap Sylvia atricapilla A blackcap is a small European warbler named for the male's neat black cap, prized for its rich song, and one of the best-documented examples of a wild bird evolving new migratory behaviour. Read the guide →
Fish NT Blackfin Icefish Chaenocephalus aceratus The blackfin icefish has pale, colourless blood, lacking the oxygen-carrying pigment haemoglobin found in nearly every other vertebrate, yet still thrives in the freezing Southern Ocean. Read the guide →
Birds LC Blackish Oystercatcher Haematopus ater The blackish oystercatcher is entirely dark-plumaged unlike its pied Magellanic relative, prying mussels and limpets directly from rocky Pacific and Atlantic shorelines. Read the guide →
Fish LC Blacknose Dace Rhinichthys atratulus The blacknose dace is one of the most reliable indicators of a healthy small stream, thriving in clean, cool water and disappearing once pollution or warming pushes conditions too far. Read the guide →
Birds NT Blackpoll Warbler Setophaga striata The blackpoll warbler flies nonstop over open ocean for up to three days during migration, one of the longest continuous flights of any songbird, first roughly doubling its body weight in fat. Read the guide →
Fish LC Blackside Darter Percina maculata The blackside darter carries a row of squarish dark blotches down its flank, a pattern that helps it disappear against gravel and sand in the moderate-current streams it prefers. Read the guide →
Fish LC Blackstripe Topminnow Fundulus notatus The blackstripe topminnow spends its life just beneath the water's surface, a bold dark stripe down its body making it one of the easiest small fish to identify in the streams it calls home. Read the guide →
Fish VU Blacktip Shark Carcharhinus limbatus The blacktip shark is a fast, energetic hunter known for leaping completely out of the water while spinning through the air, a spectacular hunting technique used to catch schooling fish from below. Read the guide →
Mammals LC Blainville's Beaked Whale Mesoplodon densirostris Blainville's beaked whale has the densest bone of any mammal, a skull so heavy it barely floats, and males carry teeth that erupt through the jaw rather than staying hidden like most whale teeth. Read the guide →
Amphibians DD Blanco Blind Salamander Eurycea robusta The Blanco blind salamander is known from only a single well and has not been documented in the wild since its initial discovery, making it one of the most poorly known amphibians in North America. Read the guide →
Reptiles EN Blanding's Turtle Emydoidea blandingii Blanding's turtle carries a bright yellow chin and throat that makes it look like it is always smiling, an appearance that belies how long-lived and slow to reproduce it actually is. Read the guide →
Mammals LC Blanford's Fox Vulpes cana Blanford's fox is an exceptionally agile climber among canids, scaling steep, rocky desert cliffs with cat-like ease using semi-retractable claws and a long balancing tail. Read the guide →
Invertebrates NE Blanket Octopus Tremoctopus violaceus In the open ocean the female blanket octopus trails a vast sheet of webbing between her arms, while the walnut-sized male dies soon after mating. Both carry stolen man o' war stingers. Read the guide →
Fish LC Bleak Alburnus alburnus The bleak is a slender, silvery surface-shoaling fish of European rivers and lakes whose scales were once used to make the shimmering coating of artificial pearls. Read the guide →
Fish LC Blenny Blenniidae A blenny is a small, big-eyed reef and tide-pool fish, and one group has evolved fangs and a genuinely aggressive habit of impersonating a harmless cleaner fish just to bite unsuspecting victims. Read the guide →
Mammals LC Blesbok Damaliscus pygargus phillipsi The blesbok carries a bold white blaze down its face, a South African grassland antelope brought back from the edge of extinction almost entirely through private game ranching. Read the guide →
Reptiles LC Blind Snake Typhlopidae A blind snake is a tiny, shiny, worm-like burrowing snake with eyes reduced to dark spots under the scales, that eats ant and termite brood, and one kind is the most widespread land snake on Earth. Read the guide →
Invertebrates LC Blister Beetle Meloidae The blister beetle produces cantharidin, a toxin potent enough to raise painful blisters on human skin and occasionally kill livestock that swallow the beetles hidden in baled hay. Read the guide →
Fish NE Blobfish Psychrolutes marcidus The blobfish looks gelatinous and mournful only after being hauled up from the deep sea, where its body is actually a normal, firm-looking fish. Low-density flesh lets it drift near the seafloor. Read the guide →
Fish NT Blonde Ray Raja brachyura The blonde ray is a large, pale, leopard-spotted ray of sandy north-eastern Atlantic seabeds that hunts fish and crustaceans and lays big egg cases, and is now Near Threatened. Read the guide →
Birds LC Blood Pheasant Ithaginis cruentus The blood pheasant carries splashes of vivid crimson across its chest and face, as though freshly wounded, an unusual colour pattern found at altitudes higher than almost any other pheasant tolerates. Read the guide →
Reptiles LC Blood Python Python brongersmalis A blood python is a stout, short-tailed Southeast Asian constrictor named for the deep red blotches often marking its body, and it is among the heaviest snakes relative to its length. Read the guide →
Invertebrates LC Bloody-Belly Comb Jelly Lampocteis cruentiventer The bloody-belly comb jelly hides a glowing red stomach inside its body, a colour that swallows light in the deep sea and conceals any bioluminescent prey glowing from within. Read the guide →
Fish LC Blue Acara Andinoacara pulcher The blue acara is speckled with iridescent turquoise flecks across a stout, hardy body, one of the more peaceful medium-sized cichlids widely recommended as an introduction to the family. Read the guide →
Invertebrates NE Blue Button Porpita porpita The blue button is often mistaken for a jellyfish but is actually a colony of specialized individual organisms, a flat, disc-shaped drifter found floating across warm ocean surfaces worldwide. Read the guide →
Fish LC Blue Catfish Ictalurus furcatus The blue catfish has grown into one of the biggest invasive species headaches in the Chesapeake Bay, a massive predator that eats nearly anything and thrives in both fresh and brackish water. Read the guide →
Invertebrates LC Blue Crab Callinectes sapidus The blue crab swims as readily as it walks, its flattened rear legs working like a pair of paddles, powering a Chesapeake Bay fishery so central to the region it shaped an entire local food culture. Read the guide →
Invertebrates LC Blue Dasher Pachydiplax longipennis The blue dasher perches with its wings angled forward and down, a distinctive posture that helps it regulate body temperature by controlling how much sunlight reaches its body. Read the guide →
Invertebrates NE Blue Dragon Sea Slug Glaucus atlanticus The blue dragon is a 3-cm sea slug that floats upside down on the sea surface, eats the Portuguese man o' war, and stores its prey's stinging cells to fire a sting worse than the original. Read the guide →
Birds LC Blue Jay Cyanocitta cristata The blue jay is a loud, crested North American crow relative whose blue is a trick of light rather than a pigment, and whose acorn-burying habit helped oak forests spread north after the last ice age. Read the guide →
Invertebrates LC Blue Land Crab Cardisoma guanhumi The blue land crab digs burrows far inland from the shore, only returning to the ocean to release its eggs, bridging land and sea for most of its adult life. Read the guide →
Invertebrates NE Blue Linckia Sea Star Linckia laevigata The blue Linckia sea star is one of the few naturally bright blue animals in the ocean, and a detached arm can sometimes regrow an entirely new body of its own. Read the guide →
Fish VU Blue Marlin Makaira nigricans The blue marlin is one of the largest and fastest bony fish, a deep-blue predator that can top 4 metres and 800 kg. It slashes its bill through schools of tuna and squid to stun them before feeding. Read the guide →
Mammals LC Blue Monkey Cercopithecus mitis The blue monkey is a common guenon of Central and East African forests with a blue-grey coat, a white throat, and troops of females led by a single adult male. Read the guide →
Invertebrates LC Blue Morpho Butterfly Morpho peleides The blue morpho butterfly flashes brilliant iridescent blue wings in flight, a colour produced entirely by microscopic scale structures rather than any blue pigment. Read the guide →
Invertebrates NE Blue Mussel Mytilus edulis The blue mussel is the dark blue-black shellfish that forms dense beds on cold northern shores, anchored by tough threads and filtering huge volumes of water, and farmed around the world for food. Read the guide →
Invertebrates LC Blue Orchard Bee Osmia lignaria The blue orchard bee pollinates fruit trees so efficiently that a few hundred individuals can do the work of tens of thousands of honeybees, a favorite among orchard growers. Read the guide →
Birds NT Blue Petrel Halobaena caerulea The blue petrel closely resembles a prion at a distance but is set apart by a distinctive white-tipped tail, and is the only member of its genus among all Southern Ocean seabirds. Read the guide →
Amphibians NT Blue Ridge Gray-Cheeked Salamander Plethodon amplus The Blue Ridge gray-cheeked salamander is confined to a small stretch of the southern Blue Ridge Mountains, told apart from its close relatives mainly by muted cheek colouring. Read the guide →
Amphibians LC Blue Ridge Two-Lined Salamander Eurycea wilderae The Blue Ridge two-lined salamander is one of several nearly identical species dividing the eastern United States, distinguished from close relatives mainly by which mountain streams it occupies. Read the guide →
Fish NT Blue Shark Prionace glauca The blue shark is a slender, indigo-backed, long-finned shark that roams every ocean, makes vast migrations, bears large litters, and is caught in greater numbers than any other shark. Read the guide →
Reptiles LC Blue Spiny Lizard Sceloporus serrifer The blue spiny lizard displays some of the most vivid blue colouration of any North American lizard, a striking contrast to the muted browns and greys most desert lizards rely on to stay hidden. Read the guide →
Fish LC Blue Tang Paracanthurus hepatus The blue tang is the electric-blue reef fish made famous as Dory. It plays dead when threatened, carries a scalpel-sharp blade at the base of its tail, and is one of the hardest marine fish to breed. Read the guide →
Birds LC Blue Tit Cyanistes caeruleus The blue tit is a tiny, acrobatic blue-and-yellow bird of European woods and gardens that hangs upside down to feed and times its single brood to the spring rush of caterpillars. Read the guide →
Reptiles EN Blue Tree Monitor Varanus macraei The blue tree monitor was unknown to science until recently, a vividly blue, fully arboreal lizard restricted to one small Indonesian island and now facing pressure from its own popularity. Read the guide →
Mammals EN Blue Whale Balaenoptera musculus The blue whale is the largest animal that has ever lived — bigger than any dinosaur — yet it eats some of the ocean's smallest creatures. Learn how it feeds, communicates, and is recovering. Read the guide →
Fish LC Blue Whiting Micromesistius poutassou The blue whiting is a small, slender, large-eyed, deep-water cod relative that swims in huge shoals over the north-eastern Atlantic slope and supports one of the largest fisheries in Europe. Read the guide →
Mammals LC Blue Wildebeest Connochaetes taurinus The blue wildebeest drives the largest land-mammal migration on Earth — over a million animals looping through the Serengeti and Mara after the rains, past lions, hyenas, and river crocodiles. Read the guide →
Birds LC Blue-And-Gold Macaw Ara ararauna The blue-and-gold macaw pairs a sky-blue back with a golden-yellow chest, one of the most recognisable large parrots of South American rainforest and a familiar sight at riverside clay licks. Read the guide →
Birds LC Blue-crowned Manakin Lepidothrix coronata The blue-crowned manakin is a small, mostly black forest bird whose males display a brilliant blue crown patch at traditional courtship arenas called leks. Read the guide →
Birds LC Blue-crowned Motmot Momotus momota The blue-crowned motmot swings its long, racket-tipped tail like a pendulum, a vivid blue crown patch standing out against otherwise green plumage. Read the guide →
Birds LC Blue-footed Booby Sula nebouxii The blue-footed booby's turquoise feet are a health badge — the bluer the feet, the better-fed the bird — and males flaunt them in a high-stepping courtship parade. Read the guide →
Birds LC Blue-Gray Tanager Thraupis episcopus The blue-gray tanager is one of the most common birds across its range, a familiar sight in gardens and parks throughout the Neotropics. Read the guide →
Birds LC Blue-headed Pionus Pionus menstruus The blue-headed pionus shows a bright blue head and neck against a green body, a relatively quiet parrot compared to many of its noisier Neotropical relatives. Read the guide →
Birds LC Blue-Headed Vireo Vireo solitarius The blue-headed vireo was once lumped with two other vireo species as a single bird before careful study of their songs and ranges revealed three genuinely distinct species hiding under one name. Read the guide →
Invertebrates NE Blue-ringed Octopus Hapalochlaena maculosa The blue-ringed octopus is a golf-ball-sized animal whose bite carries enough tetrodotoxin to paralyse and kill a person. It flashes 50–60 iridescent blue rings as a warning before it strikes. Read the guide →
Fish LC Blue-spotted Ribbontail Ray Taeniura lymma The blue-spotted ribbontail ray is a small coral-reef stingray marked with electric-blue spots that warn of two venomous tail spines. It rarely buries itself, sheltering under coral ledges instead. Read the guide →
Amphibians LC Blue-spotted Salamander Ambystoma laterale A blue-spotted salamander is a small, dark, blue-flecked salamander of the Great Lakes region that breeds with a relative to produce all-female hybrid lineages found in almost no other vertebrate. Read the guide →
Invertebrates LC Blue-tailed Damselfly Ischnura elegans The blue-tailed damselfly is a slender black damselfly with a single bright blue segment at the tip of the tail, tolerant of small and polluted waters and found around ponds and ditches. Read the guide →
Reptiles LC Blue-tongued Skink Tiliqua scincoides The blue-tongued skink is a stout, short-legged Australian lizard that startles predators by flashing a broad ultraviolet-blue tongue. It eats snails and fruit, bears live young, and makes a calm pet. Read the guide →
Birds LC Blue-winged Kookaburra Dacelo leachii The blue-winged kookaburra shares its larger relative's land-hunting habits, but gives a harsher call and shows a flash of blue in the wing that the laughing kookaburra lacks. Read the guide →
Birds LC Blue-Winged Warbler Vermivora cyanoptera The blue-winged warbler has expanded so successfully that it now regularly interbreeds with its declining relative, the golden-winged warbler, gradually absorbing it wherever the two ranges overlap. Read the guide →
Fish NT Blueback Herring Alosa aestivalis The blueback herring migrates from the ocean into freshwater rivers in enormous numbers each spring to spawn, a journey that once supported major fisheries and still feeds many predators. Read the guide →
Birds LC Bluebird Sialia A bluebird is a small, brilliant-blue North American thrush that nests in tree holes and hunts insects from a low perch, and its 20th-century decline was reversed by a nest-box movement. Read the guide →
Invertebrates NE Bluebottle Calliphora vomitoria The bluebottle is a loud, metallic blue blowfly that finds carrion by smell, whose fast-growing maggots recycle dead animals and are used by forensic scientists to estimate time of death. Read the guide →
Fish LC Bluebreast Darter Etheostoma camurum The bluebreast darter's breeding males flush a vivid blue chest and orange-red fins, a display so demanding on clean, fast-flowing water that the species disappears quickly once a stream is polluted. Read the guide →
Fish LC Bluefin Killifish Lucania goodei A breeding male bluefin killifish develops fins so vividly blue that the species is kept purely for its colour in home aquariums, despite being a small, unassuming wild fish most of the year. Read the guide →
Fish LC Bluegill Lepomis macrochirus The bluegill is the small, deep-bodied sunfish behind more first fish caught in North America than any other species, and its breeding colonies feature a classic case of three different kinds of male. Read the guide →
Fish LC Bluehead Chub Nocomis leptocephalus The bluehead chub builds a large gravel mound nest that other minnow species deliberately spawn over, making this one fish's construction project a shared nursery for an entire local fish community. Read the guide →
Fish LC Bluespotted Sunfish Enneacanthus gloriosus The bluespotted sunfish is scattered with iridescent blue flecks across its dark body, a pattern so fine it looks hand-painted, and it thrives in slow, tannin-stained waters most other sunfish avoid. Read the guide →
Reptiles EN Blunt-Nosed Leopard Lizard Gambelia sila The blunt-nosed leopard lizard has lost more than half its historical San Joaquin Valley grassland to agriculture, making it one of the few lizards protected under the US Endangered Species Act. Read the guide →
Fish LC Bluntnose Minnow Pimephales notatus The bluntnose minnow gets its name from a rounded snout that overhangs its small mouth, and breeding males grow a fleshy pad used to clean and guard the nest. Read the guide →
Fish NT Bluntnose Sixgill Shark Hexanchus griseus The bluntnose sixgill shark has six gill slits instead of five, a body plan barely changed since before the dinosaurs. It hides in cold deep water by day, rises at night, and can top five metres. Read the guide →
Reptiles NE Boa Boidae A boa is a non-venomous constrictor that mostly gives birth to live young rather than laying eggs, and includes the green anaconda, the heaviest snake in the world. Read the guide →
Reptiles LC Boa Constrictor Boa constrictor The boa constrictor is a large non-venomous snake of the Americas that kills by cutting off blood flow, not by suffocation, and gives birth to live young. It is a popular but long-lived, powerful pet. Read the guide →
Birds LC Boat-billed Heron Cochlearius cochlearius The boat-billed heron carries an enormously broad, shovel-shaped bill unlike any other heron, a tool suited to a nocturnal life spent hunting through dark mangrove waters. Read the guide →
Mammals LC Bobak Marmot Marmota bobak The bobak marmot is a stocky marmot of the Eurasian steppe that digs deep family burrows, hibernates for much of the year, and has vanished from parts of its former range. Read the guide →
Invertebrates NE Bobbit Worm Eunice aphroditois The bobbit worm buries its long body in the seafloor with only antennae and jaws exposed, then strikes passing fish so fast it can slice them in half. Buried individuals may exceed three metres. Read the guide →
Mammals LC Bobcat Lynx rufus The bobcat is North America's most abundant wild cat, a tufted-eared, bob-tailed predator twice the size of a house cat that thrives from swamps to deserts to the edges of cities. Read the guide →
Birds LC Bobolink Dolichonyx oryzivorus The bobolink wears its breeding plumage backwards by songbird standards, pale on top and black below, and migrates roughly 20,000 kilometres round trip between two continents' grasslands. Read the guide →
Invertebrates LC Bobtail Squid Euprymna scolopes The bobtail squid hosts glowing bacteria in a special light organ, matching moonlight filtering down from above to erase its own shadow from predators hunting on the seafloor below. Read the guide →
Fish EN Boesemani Rainbowfish Melanotaenia boesemani The boesemani rainbowfish shows a sharp colour split along its body, blue-grey at the front and vivid orange-yellow at the back, native to only one small lake system in Indonesia. Read the guide →
Reptiles CR Bog Turtle Glyptemys muhlenbergii The bog turtle is North America's smallest turtle, a palm-sized species with an orange neck blaze, now one of the continent's most endangered, clinging to scattered spring-fed bogs. Read the guide →
Invertebrates NE Bolas Spider Mastophoreae The bolas spider builds no web. It hangs from a thread holding a sticky blob of silk, releases a chemical copy of a female moth's scent, and swings the blob like a lasso to catch the males that come. Read the guide →
Invertebrates LC Boll Weevil Anthonomus grandis The boll weevil devastated American cotton so thoroughly after arriving from Mexico that one Alabama town built a monument honoring the pest for forcing farmers to diversify. Read the guide →
Reptiles EN Bolson Tortoise Gopherus flavomarginatus The bolson tortoise is the largest terrestrial reptile native to North America, digging burrows deep enough to shelter other desert species while its own population has shrunk to a single wild region. Read the guide →
Invertebrates NE Bombardier Beetle Brachinus The bombardier beetle defends itself by mixing two chemicals in an internal reaction chamber and firing the boiling, caustic result out of its rear in rapid pulses, aimed with a swivelling nozzle. Read the guide →
Birds LC Bonaparte's Gull Chroicocephalus philadelphia Bonaparte's gull breaks one of the most consistent rules in the gull family by nesting in trees, a habit almost unheard of among gulls, which overwhelmingly nest on open ground. Read the guide →
Fish NT Bonefish Albula vulpes The bonefish is the grey ghost of tropical shallows, a fast, silver, spook-prone fish that is the most prized target in saltwater fly fishing and almost always released. Read the guide →
Mammals NT Bongo Tragelaphus eurycerus The bongo is one of the largest forest antelope in the world, a striking chestnut-coated animal whose mountain population has become one of the most critically endangered large mammals in Africa. Read the guide →
Mammals LC Bonnet Macaque Macaca radiata The bonnet macaque is named for a whorl of hair radiating from the crown of its head like a woven cap, a common sight around temples across southern India. Read the guide →
Fish LC Bonnethead Shark Sphyrna tiburo The bonnethead is the smallest hammerhead shark and the only shark confirmed to be genuinely omnivorous, digesting seagrass as well as eating crabs and shrimp with its shovel-shaped head. Read the guide →
Mammals EN Bonobo Pan paniscus The bonobo is one of humanity's two closest living relatives, sharing about 98.7% of our DNA. Its societies are led by females, largely peaceful, and famous for defusing conflict with sex. Read the guide →
Invertebrates LC Booklouse Psocoptera A booklouse is a tiny, harmless insect that feeds on mould on damp paper and stored food, often appearing suddenly in new or humid buildings, and true lice evolved from within this same group. Read the guide →
Reptiles LC Boomslang Dispholidus typus The boomslang is a slender, big-eyed African tree snake with rear fangs and a slow-acting haemotoxic venom. It killed the herpetologist Karl Schmidt in 1957 after a bite from a juvenile. Read the guide →
Birds LC Booted Racket-tail Ocreatus underwoodii The booted racket-tail carries fluffy white leg puffs resembling tiny boots and a long tail ending in bare rackets, among the most distinctively adorned small hummingbirds in the Andes. Read the guide →
Invertebrates NE Bootlace Worm Lineus longissimus The bootlace worm may be the longest animal on Earth. One washed up in Scotland was recorded at around 55 metres, though it is only a few millimetres wide and coils into a dark, slimy knot. Read the guide →
Amphibians LC Boreal Chorus Frog Pseudacris maculata The boreal chorus frog calls before almost any other frog each spring, sometimes trilling from beneath a thin layer of ice, and it can even survive being partly frozen solid during a late cold snap. Read the guide →
Amphibians EN Bornean Flat-headed Frog Barbourula kalimantanensis The Bornean flat-headed frog is the only frog known to have no lungs at all. It breathes entirely through its skin, and its flattened body lets it stay pinned to the bed of cold, fast forest streams. Read the guide →
Mammals CR Bornean Orangutan Pongo pygmaeus The Bornean orangutan is the largest tree-living animal on Earth and the most solitary great ape. It maps hundreds of fruiting trees from memory and is Critically Endangered from forest loss. Read the guide →
Mammals LC Botta's Pocket Gopher Thomomys bottae Botta's pocket gopher spends nearly its whole life in self-dug tunnels, using fur-lined cheek pouches to carry food and lips that close behind its teeth to keep out soil. Read the guide →
Mammals LC Bottlenose Dolphin Tursiops truncatus The bottlenose dolphin hunts with sound, calls other dolphins by name, and uses tools. Learn how echolocation works, why pods cooperate, and what threatens this widespread ocean mammal. Read the guide →
Birds VU Bounty Shag Leucocarbo ranfurlyi The Bounty shag breeds only on the Bounty Islands, a tiny cluster of bare granite rocks in the Southern Ocean, making it one of the most narrowly confined blue-eyed shag species alive. Read the guide →
Birds LC Bowerbird Ptilonorhynchidae A male bowerbird builds and decorates an elaborate structure of sticks and colour-sorted objects purely to impress a mate, one of the most complex construction behaviours in the animal kingdom. Read the guide →
Fish LC Bowfin Amia calva The bowfin is the last survivor of a fish order otherwise extinct for tens of millions of years. It gulps air to live in stagnant swamps, and the male guards a swarm of thousands of young for weeks. Read the guide →
Mammals LC Bowhead Whale Balaena mysticetus The bowhead whale can live well over 200 years, likely the longest-lived mammal on Earth, an Arctic specialist with the thickest blubber of any whale, capable of breaking through sea ice from below. Read the guide →
Invertebrates LC Box Elder Bug Boisea trivittata The box elder bug gathers by the hundreds on sun-warmed walls each autumn, a harmless nuisance that invades homes without biting, stinging, or causing damage. Read the guide →
Invertebrates NE Box Jellyfish Chironex fleckeri The Australian box jellyfish carries enough venom to kill a person in minutes, hunts actively with 24 eyes, and swims rather than drifts. Learn what makes this cube-shaped animal so deadly. Read the guide →
Reptiles VU Box Turtle Terrapene A box turtle is a small North American land turtle whose hinged lower shell folds like a box to seal it inside, and it may spend its whole life within a few hundred metres of where it hatched. Read the guide →
Invertebrates LC Boxer Crab Lybia The boxer crab holds a small sea anemone in each claw like a pair of stinging boxing gloves, waving them at threats and even splitting one anemone in half to grow a matching second glove. Read the guide →
Fish LC Boxfish Ostraciidae The boxfish encases its body in a rigid, bony carapace of fused hexagonal plates, leaving only its fins free to move and its stiff, boxy shape a genuine engineering curiosity. Read the guide →
Reptiles LC Brahminy Blind Snake Indotyphlops braminus The brahminy blind snake is a tiny, shiny, earthworm-like snake with no working eyes that has spread to warm regions worldwide inside potted plants, and every one of them is female. Read the guide →
Invertebrates NT Brain Coral Diploria A brain coral grows as a rounded dome covered in winding, maze-like grooves that resemble the folds of an actual brain, a colony of thousands of tiny polyps that can live for centuries. Read the guide →
Fish EN Bramble Shark Echinorhinus brucus The bramble shark is covered in scattered, thorn-like denticles rather than the smooth, evenly spaced scales of most sharks, giving its skin a bramble-like texture that inspired its common name. Read the guide →
Reptiles LC Brazilian Rainbow Boa Epicrates cenchria The Brazilian rainbow boa's smooth scales carry microscopic ridges that split light into a shimmering rainbow sheen across its reddish body. It hunts warm-blooded prey at night by heat-sensing pits. Read the guide →
Invertebrates NE Brazilian Salmon Pink Birdeater Lasiodora parahybana The Brazilian salmon pink birdeater ranks among the largest tarantulas in the world by leg span, yet remains surprisingly docile and slow-moving for a spider its size. Read the guide →
Birds LC Brazilian Teal Amazonetta brasiliensis The Brazilian teal is one of South America's most common ducks, identified by a bright red bill and legs in males against otherwise brown plumage. Read the guide →
Invertebrates NE Brazilian Wandering Spider Phoneutria nigriventer The Brazilian wandering spider is a large, aggressive nocturnal hunter of the American tropics with one of the most potent venoms of any spider. It builds no web and roams the forest floor. Read the guide →
Reptiles LC Brazos Water Snake Nerodia harteri The Brazos water snake exists naturally only along a single Texas river system, favoring rocky, fast-flowing riffles over the still water most water snakes prefer. Read the guide →
Amphibians LC Brimley's Chorus Frog Pseudacris brimleyi Brimley's chorus frog is confined to a narrow strip of the Atlantic coastal plain, calling from grassy ditches with a rasping call easily confused with its more widespread upland relative. Read the guide →
Invertebrates LC Brimstone Butterfly Gonepteryx rhamni The brimstone is a leaf-shaped, sulphur-yellow butterfly that can live for about a year, hibernating among ivy and holly and often the first butterfly seen on the wing in spring. Read the guide →
Fish LC Brindled Madtom Noturus miurus The brindled madtom carries a mottled, saddle-like blotch pattern along its back, and like its close relatives it packs a genuinely painful venomous sting into a fish barely longer than a finger. Read the guide →
Invertebrates LC Brine Fly Ephydridae The brine fly develops inside water many times saltier than the ocean, surviving alkaline lakes lethal to nearly every other insect, its sheer numbers feeding entire flocks of migratory birds. Read the guide →
Invertebrates LC Brine Shrimp Artemia A brine shrimp is a tiny crustacean of salt lakes that filters algae from the water, lays eggs that survive years of drying, and is sold worldwide as fish food and, as sea monkeys, as a novelty pet. Read the guide →
Invertebrates LC Bristle Worm Polychaeta A bristle worm moves using rows of paired, leg-like paddles fringed with fine, sometimes stinging bristles, and some species detach a section of their body packed with eggs to spawn at the surface. Read the guide →
Fish LC Bristlemouth Gonostomatidae The bristlemouth may be the single most numerous vertebrate on the planet, a finger-length deep-sea fish found in numbers likely reaching the hundreds of trillions across the world's oceans. Read the guide →
Fish NE Bristlenose Pleco Ancistrus cirrhosus The bristlenose pleco stays far smaller than giant pleco relatives, making it a practical algae-eating catfish for home aquariums, with males growing fleshy tentacles on the face. Read the guide →
Invertebrates LC Bristletail Archaeognatha A bristletail is a wingless jumping insect older in lineage than the silverfish, with a humped back and huge eyes, that flings itself airborne to escape and can survive being washed by the tide. Read the guide →
Invertebrates LC Brittle Star Ophiuroidea A brittle star moves with a fast, snake-like wriggle of its five thin arms, a much quicker escape than its slower starfish relatives, and will readily shed an arm to a predator and regrow it. Read the guide →
Birds LC Broad-billed Prion Pachyptila vittata The broad-billed prion is the largest prion species, with an unusually wide bill packed with fine comb-like structures that filter plankton from the sea surface almost like a miniature baleen whale. Read the guide →
Invertebrates LC Broad-bodied Chaser Libellula depressa The broad-bodied chaser is a stocky, flat-bodied dragonfly whose male is dusted pale blue, and one of the first species to colonise new garden ponds. Read the guide →
Reptiles VU Broad-headed Snake Hoplocephalus bungaroides The broad-headed snake is a rare, venomous Australian snake restricted to the sandstone country around Sydney, sheltering under rock slabs in winter and in tree hollows in summer. Read the guide →
Reptiles LC Broad-snouted Caiman Caiman latirostris The broad-snouted caiman is a South American crocodilian with a wide, short snout suited to crushing snails, and one of the species managed by a sustainable ranching programme in Argentina. Read the guide →
Reptiles LC Broadhead Skink Plestiodon laticeps The male broadhead skink develops a strikingly wide, bright orange head during breeding season, a visible signal backed by a genuinely powerful bite for the largest skink in the eastern US. Read the guide →
Fish LC Brook Lamprey Lampetra planeri The brook lamprey is a small, eel-like freshwater lamprey that spends years as a blind, silt-dwelling larva, then transforms, spawns in gravel, and dies without ever feeding as an adult. Read the guide →
Fish LC Brook Silverside Labidesthes sicculus The brook silverside is capable of skittering across the water's surface in a series of rapid skips when startled, a behaviour distinctive enough to give the species one of its alternate common names. Read the guide →
Fish LC Brook Stickleback Culaea inconstans The brook stickleback lacks the pelvic spines and armour plating of its well-known marine relative, a small, spineless freshwater fish whose males build and defend a woven nest of plant material. Read the guide →
Fish LC Brook Trout Salvelinus fontinalis The brook trout is a marbled, red-spotted fish of cold, clean streams in eastern North America that is really a char, an emblem of unspoilt water that vanishes when its streams warm or silt up. Read the guide →
Fish LC Brotula Bythitidae The brotula gives birth to live young rather than laying eggs, setting it apart from its close relative the cusk-eel, with some species living out their entire lives deep inside dark underwater caves. Read the guide →
Reptiles LC Brown Anole Anolis sagrei The brown anole is a small Caribbean lizard whose invasion of the southern US pushed the native green anole up into the treetops, driving one of the clearest recorded cases of rapid evolution. Read the guide →
Mammals LC Brown Antechinus Antechinus stuartii The brown antechinus is a small Australian marsupial whose males mate frantically for two weeks each year and then all die, their bodies destroyed by their own stress hormones. Read the guide →
Reptiles LC Brown Basilisk Basiliscus vittatus The brown basilisk can sprint across the surface of water on its hind legs alone, slapping specialized fringed toes down fast enough to avoid sinking before momentum runs out. Read the guide →
Mammals LC Brown Bear Ursus arctos The brown bear is the most widespread bear on Earth, from Spain to Alaska, and includes the grizzly and the giant Kodiak. Learn how it hibernates, what it eats, and how a cub is born mid-sleep. Read the guide →
Fish LC Brown Bullhead Ameiurus nebulosus The brown bullhead can taste food before it even reaches its mouth, using sensitive barbels and skin covered in taste buds, and it tolerates water so low in oxygen it would kill most other fish. Read the guide →
Invertebrates LC Brown Hawker Aeshna grandis The brown hawker is a large dragonfly with a rich brown body and amber-tinted wings that glow golden in the sun, patrolling ponds and canals from midsummer into autumn. Read the guide →
Mammals NT Brown Hyena Parahyaena brunnea The brown hyena is a shaggy, dark scavenger of southern Africa's deserts and savannas that travels long distances alone at night and carries food back to a communal den. Read the guide →
Mammals LC Brown Long-eared Bat Plecotus auritus The brown long-eared bat has ears nearly as long as its body, listens for the faint rustle of moths on leaves, and curls its ears like ram's horns when it rests. Read the guide →
Mammals LC Brown Mongoose Urva fusca The brown mongoose keeps to the cool, wet hill forests of India's Western Ghats and Sri Lanka, a uniformly dark, poorly studied species rarely seen away from dense cover. Read the guide →
Mammals LC Brown Rat Rattus norvegicus The brown rat is one of the most successful mammals on Earth — a smart, social, adaptable rodent that reached every continent by ship, shows empathy and ticklishness, and became the lab rat. Read the guide →
Invertebrates NE Brown Recluse Spider Loxosceles reclusa The brown recluse carries a dark violin-shaped mark on its back and hides in quiet dry corners. Its bite can occasionally cause a slow-spreading, tissue-destroying wound, though most bites are minor. Read the guide →
Invertebrates NE Brown Shrimp Crangon crangon The brown shrimp is a small, sandy-coloured shrimp of European estuaries and sandy shores that matches its background, buries itself in sand, and is the source of potted shrimps. Read the guide →
Birds LC Brown Skua Stercorarius antarcticus The brown skua is the largest of the skuas, an aggressive predator and scavenger that raids penguin colonies for eggs and chicks across subantarctic islands and the Antarctic Peninsula. Read the guide →
Mammals CR Brown Spider Monkey Ateles hybridus The brown spider monkey is a Critically Endangered, long-limbed fruit eater of Colombia and Venezuela that has lost most of its forest and ranks among the world's most threatened primates. Read the guide →
Birds LC Brown Thrasher Toxostoma rufum The brown thrasher can sing over a thousand distinct phrases, one of the largest song repertoires of any North American bird, typically repeating each one exactly twice. Read the guide →
Reptiles LC Brown Tree Snake Boiga irregularis The brown tree snake is an ordinary night-hunting tree snake in its native range, but as a stowaway on Guam it wiped out most of the island's forest birds and still causes power blackouts. Read the guide →
Fish LC Brown Trout Salmo trutta The brown trout is the trout of European rivers and the birthplace of fly fishing, one species ranging from small stream fish to sea-run giants, and a major invasive threat where it was introduced. Read the guide →
Reptiles LC Brown Water Snake Nerodia taxispilota The brown water snake is the largest North American water snake, so frequently mistaken for the venomous cottonmouth that it carries the nickname false moccasin despite lacking any venom of its own. Read the guide →
Birds LC Brown-hooded Kingfisher Halcyon albiventris The brown-hooded kingfisher announces itself with a loud, descending call from woodland edges across southern Africa, a mostly insect-eating hunter that rarely bothers with fish at all. Read the guide →
Amphibians LC Brownback Salamander Eurycea aquatica The brownback salamander was only recognised as its own species after genetic study separated it from the wider dwarf salamander complex, a distinction invisible from appearance alone. Read the guide →
Mammals VU Brush-Tailed Rock-Wallaby Petrogale penicillata The brush-tailed rock-wallaby bounds across near-vertical cliff faces with astonishing agility, using its long, thick tail purely for balance rather than support. Read the guide →
Mammals LC Bryde's Whale Balaenoptera brydei Bryde's whale is one of the only baleen whales that remains in warm tropical waters year-round rather than migrating to polar feeding grounds, identifiable by three parallel ridges atop its head. Read the guide →
Invertebrates LC Bryozoan Bryozoa A bryozoan colony is built from thousands of genetically identical microscopic animals, each living in its own tiny box-like chamber, working together as a single encrusting or branching structure. Read the guide →
Invertebrates NE Bubble-tip Anemone Entacmaea quadricolor The bubble-tip anemone can grow bulb-shaped swellings at the ends of its tentacles, and hosts more species of clownfish than any other anemone found on coral reefs. Read the guide →
Birds LC Budgerigar Melopsittacus undulatus The budgerigar roams the Australian outback in nomadic flocks that can number in the thousands, chasing unpredictable rainfall across the interior rather than settling permanently anywhere. Read the guide →
Amphibians LC Budgett's Frog Lepidobatrachus laevis Budgett's frog is a flat, wide-mouthed aquatic frog of the South American Chaco that screams and lunges with its mouth gaping when threatened, and has two fangs on its lower jaw. Read the guide →
Birds LC Buff-necked Ibis Theristicus caudatus The buff-necked ibis forages across open grassland rather than wading through deep water like most ibis species, using its long curved bill to probe soil for worms and insects. Read the guide →
Birds LC Buff-throated Woodcreeper Xiphorhynchus guttatus The buff-throated woodcreeper spirals up tree trunks probing bark for insects, identified by pale buff spotting across the throat and underparts. Read the guide →
Invertebrates NE Buff-tip Phalera bucephala The buff-tip is a silvery-grey moth that looks remarkably like a snapped birch twig when at rest, and whose yellow-and-black caterpillars feed together in groups on trees. Read the guide →
Birds LC Bulbul Pycnonotidae The bulbul fills forests and gardens across Africa and Asia with one of the more familiar, cheerful bird calls around, an adaptable songbird equally at home in wilderness or busy urban parks. Read the guide →
Fish VU Bull Shark Carcharhinus leucas The bull shark is the shark that swims up rivers — hundreds or thousands of kilometres into fresh water. Learn how it survives there, why it's rated among the most dangerous sharks, and its status. Read the guide →
Fish VU Bull Trout Salvelinus confluentus The bull trout needs colder, cleaner water than any of its relatives, and unlike most trout it keeps eating other fish as an adult instead of switching mainly to invertebrates. Read the guide →
Birds NT Buller's Albatross Thalassarche bulleri Buller's albatross has a distinctive pale grey head topped with a darker cap and a two-toned black-and-yellow bill, breeding on a small number of remote New Zealand islands. Read the guide →
Invertebrates NE Bullet Ant Paraponera clavata The bullet ant delivers the most painful insect sting on Earth — victims compare it to being shot, and the agony comes in waves for up to a day. Read the guide →
Amphibians NE Bullfrog Lithobates, Pyxicephalus, and others A bullfrog is any of several large, loud, predatory frogs on different continents that share a booming call and an appetite for anything they can swallow, from insects to birds and snakes. Read the guide →
Fish LC Bullhead Minnow Pimephales vigilax The bullhead minnow shares its common name with an entirely unrelated group of catfish, a small, tolerant minnow that thrives in murky, silty water many other minnow species avoid. Read the guide →
Invertebrates LC Bumblebee Bombus terrestris The bumblebee is a large, furry bee that shivers to warm up, flies in cold and rain, and shakes pollen loose with a burst of vibration that many crops depend on and honeybees cannot do. Read the guide →
Fish LC Bumblebee Cichlid Pseudotropheus crabro The bumblebee cichlid wears the yellow-and-black bands of its insect namesake, a pattern that closely resembles a bottom-dwelling catfish and may help it sneak close to mouthbrooding females. Read the guide →
Invertebrates NE Bumblebee Millipede Anadenobolus monilicornis The bumblebee millipede carries bold yellow and black banding across its body, a harmless detritivore from the Caribbean popular in the terrarium hobby for its vivid colouring. Read the guide →
Fish VU Bumphead Parrotfish Bolbometopon muricatum The bumphead parrotfish is the giant of its family, a metre-long reef grazer that headbutts living coral, grinds it up, and turns it into the white sand of a tropical beach. Read the guide →
Birds LC Bunting Emberizidae Bunting is a name shared by two unrelated songbird groups, dumpy Old World seed-eaters in one family and brilliantly coloured New World finches in another, with almost nothing but the name in common. Read the guide →
Fish LC Burbot Lota lota The burbot is the only member of the cod family that lives in fresh water, a mottled, barbel-chinned predator of cold northern lakes that spawns in a writhing ball under midwinter ice. Read the guide →
Mammals DD Burmeister's Porpoise Phocoena spinipinnis Burmeister's porpoise is found along the coasts of South America from Peru to Argentina, a small, shy porpoise rarely seen at the surface and often caught as accidental bycatch. Read the guide →
Reptiles VU Burmese Python Python bivittatus The Burmese python is one of the largest snakes in the world, a heavy-bodied constrictor from Southeast Asia that has become a devastating invasive predator in the Florida Everglades. Read the guide →
Reptiles CR Burmese Star Tortoise Geochelone platynota The Burmese star tortoise is a domed Myanmar tortoise with a star-patterned shell, driven almost extinct in the wild by the pet trade and now being brought back by captive breeding. Read the guide →
Mammals VU Burrowing Bettong Bettongia lesueur The burrowing bettong, or boodie, is the only kangaroo relative that lives underground in burrows, a species now extinct across the entire Australian mainland. Read the guide →
Birds LC Burrowing Owl Athene cunicularia The burrowing owl is a small, long-legged owl that lives underground in prairie dog holes and is active by day. It lines its nest with dung to attract dung beetles to eat. Read the guide →
Birds NT Burrowing Parrot Cyanoliseus patagonus The burrowing parrot nests in colonies of tens of thousands of cliffside burrows, forming some of the largest parrot colonies found anywhere on Earth across the open steppe of Patagonia. Read the guide →
Invertebrates LC Burying Beetle Nicrophorus spp. The burying beetle detects a dead animal from remarkable distances, then works with a mate to bury and preserve the carcass and feed the larvae directly, rare parental care for an insect. Read the guide →
Mammals NT Bush Dog Speothos venaticus The bush dog is a small, stocky South American canid that hunts cooperatively in packs and swims readily, pursuing prey through water as confidently as it does on land. Read the guide →
Mammals LC Bush Rat Rattus fuscipes The bush rat is a native Australian forest rat, distinct from the introduced black and brown rats, that forages at night and eats underground fungi whose spores it helps to spread. Read the guide →
Reptiles LC Bush Viper Atheris A bush viper is an African tree-dwelling venomous snake with unusually rough, keeled, sometimes bristle-like scales, with species ranging in colour from vivid green to bright yellow and orange. Read the guide →
Mammals LC Bushbuck Tragelaphus sylvaticus The bushbuck is the smallest of the spiral-horned antelope, a solitary, secretive forest dweller marked with white spots and stripes that freezes rather than flees when threatened. Read the guide →
Reptiles VU Bushmaster Lachesis muta The bushmaster is the longest venomous snake in the Americas and the longest pit viper on Earth — to 3.6 m. Unusually for a viper it lays eggs and guards them, and can ambush one trail for weeks. Read the guide →
Mammals LC Bushpig Potamochoerus larvatus The bushpig is a shaggy, nocturnal wild pig of eastern and southern Africa with a pale crest of hair along its back, a notorious raider of crops, and a favourite prey of leopards. Read the guide →
Birds LC Bushtit Psaltriparus minimus The bushtit weaves a hanging, sock-shaped nest from spiderweb and moss that takes weeks to build, then travels in large, constantly chattering flocks the rest of the year. Read the guide →
Mammals LC Bushveld Elephant Shrew Elephantulus intufi The bushveld elephant shrew ranges across open savanna woodland in southern Africa, a monogamous, trail-patrolling insectivore sharing dry thornveld habitat with far larger grazers. Read the guide →
Mammals LC Bushy-Tailed Mongoose Bdeogale crassicauda The bushy-tailed mongoose carries an unusually thick, fox-like tail rather than the slender tail typical of most mongoose species, a poorly studied East African forest dweller. Read the guide →
Mammals LC Bushy-tailed Woodrat Neotoma cinerea The bushy-tailed woodrat, or packrat, hoards sticks and objects in nests whose layered ancient remains let scientists reconstruct past climates and plant communities. Read the guide →
Birds LC Butcherbird Cracticus spp. The butcherbird impales captured prey on thorns or wedges it into forked branches, a genuine larder-building habit that gives this richly-voiced Australasian songbird its unusually grim common name. Read the guide →
Reptiles LC Butler's Garter Snake Thamnophis butleri Butler's garter snake stays remarkably close to home for life, rarely straying far from where it was born, a stationary lifestyle unusual among North American garter snakes. Read the guide →
Invertebrates NE Butterfly Papilionoidea A butterfly is a day-flying insect of the moth order, feeding through a coiled tongue, tasting with its feet, and beginning life as a leaf-eating caterpillar that rebuilds itself inside a chrysalis. Read the guide →
Invertebrates LC By-the-Wind Sailor Velella velella The by-the-wind sailor drifts across the open ocean surface on a stiff, diagonal sail, a colony of specialized individuals often mistaken for a small jellyfish or a miniature Portuguese man o' war. Read the guide →
Invertebrates LC Cabbage White Pieris rapae The cabbage white was accidentally introduced to North America in the 19th century and has since become one of its most widespread butterflies, its caterpillar a well-known pest of garden cabbage. Read the guide →
Mammals LC Cacomistle Bassariscus sumichrasti The cacomistle spends nearly its entire life in the forest canopy, a close relative of the ringtail with a much longer tail, used for balance while leaping between branches high above the ground. Read the guide →
Birds LC Cactus Wren Campylorhynchus brunneicapillus The cactus wren builds a football-shaped nest tucked deep inside a spiny cholla or saguaro cactus, using the plant's own defenses to keep predators away from its eggs and chicks. Read the guide →
Invertebrates LC Caddisfly Trichoptera A caddisfly larva builds a protective case from silk and whatever is around, sand, gravel, twigs, or shells, and artists exploit the trick by giving them gold and gems to build with instead. Read the guide →
Amphibians VU Caddo Mountain Salamander Plethodon caddoensis The Caddo Mountain salamander survives only in a small cluster of mountains in the Ouachita range of Arkansas, one of several extremely narrow-range lungless salamanders found nowhere else on Earth. Read the guide →
Amphibians NE Caecilian Gymnophiona Caecilians are the third, least-known amphibian order — limbless burrowers that look like large earthworms, feel their way with a pair of tentacles, and in some the young eat the mother's skin. Read the guide →
Reptiles LC Caiman Caimaninae A caiman is a Central and South American crocodilian, mostly smaller than a true alligator, ranging from the metre-long dwarf caiman to the black caiman, which rivals the largest crocodiles. Read the guide →
Reptiles LC Caiman Lizard Dracaena guianensis The caiman lizard is a large semi-aquatic South American lizard that eats almost nothing but snails, crushing the shells with broad molar-like back teeth and spitting out the fragments. Read the guide →
Amphibians LC Cajun Chorus Frog Pseudacris fouquettei The Cajun chorus frog was only recently recognized as its own species, split from the upland chorus frog after genetic evidence showed the western Gulf Coast population was genuinely distinct. Read the guide →
Invertebrates LC Calico Pennant Celithemis elisa The calico pennant carries a row of small heart-shaped red or yellow markings down the middle of its abdomen, a pattern distinctive enough among dragonflies to make identification almost immediate. Read the guide →
Birds CR California Condor Gymnogyps californianus The California condor is the largest flying bird in North America, with a 3-metre wingspan. In 1987 just 22 were left; the wild population is now over 300 after decades of captive breeding. Read the guide →
Mammals LC California Ground Squirrel Otospermophilus beecheyi The California ground squirrel faces down rattlesnakes by fluffing and heating its tail to send an infrared warning, and is partly resistant to the snake's venom. Read the guide →
Reptiles LC California Kingsnake Lampropeltis californiae The California kingsnake is a glossy, banded constrictor of the western US that eats rodents, birds, and other snakes, including rattlesnakes, whose venom it is largely immune to. Read the guide →
Reptiles LC California Legless Lizard Anniella pulchra The California legless lizard spends nearly its life swimming through loose sandy soil, and its smooth, silvery scales and missing legs leave it constantly mistaken for a snake. Read the guide →
Reptiles LC California Mountain Kingsnake Lampropeltis zonata The California mountain kingsnake mimics venomous coral snakes across much of a range where no coral snake actually lives, a mimicry puzzle without an obvious model. Read the guide →
Amphibians LC California Newt Taricha torosa A California newt is a coast-range salamander whose skin holds enough tetrodotoxin to kill a person if eaten, locked in an evolutionary arms race with the garter snakes that eat it anyway. Read the guide →
Birds LC California Quail Callipepla californica The California quail wears a single forward-curving black plume above its head like a tiny question mark, an emblem distinctive enough to make the species the official state bird of California. Read the guide →
Amphibians VU California Red-legged Frog Rana draytonii The California red-legged frog is the largest native frog in the western US and the model for Mark Twain's jumping-frog story; introduced bullfrogs and lost wetlands have made it a threatened species. Read the guide →
Mammals LC California Sea Lion Zalophus californianus The California sea lion is the barking pinniped of Pacific piers and marine parks — a fast, agile, intelligent swimmer that walks on all fours on land and can learn abstract logic. Read the guide →
Birds LC California Thrasher Toxostoma redivivum The California thrasher rarely flies more than a short distance at a time, preferring to run through dense chaparral on foot, a ground-hugging lifestyle unusual for a bird capable of flight. Read the guide →
Amphibians VU California Tiger Salamander Ambystoma californiense The California tiger salamander spends most of the year in rodent burrows, surfacing on rainy nights to breed in vernal pools; farmland, sprawl, and an invasive cousin have made it threatened. Read the guide →
Amphibians LC California Treefrog Pseudacris cadaverina The California treefrog's dull, cadaver-gray coloring, the source of its unflattering scientific name, camouflages it perfectly against the granite boulders of canyon streams. Read the guide →
Birds LC Calliope Hummingbird Selasphorus calliope The calliope hummingbird is the smallest breeding bird in North America, yet it migrates thousands of kilometers each year between mountain meadows and Mexican wintering grounds. Read the guide →
Invertebrates LC Camel Cricket Rhaphidophoridae A camel cricket is a humpbacked, long-legged, wingless cricket of caves, cellars, and damp leaf litter that has no song and no ears, and defends itself by leaping straight at whatever startles it. Read the guide →
Invertebrates NE Camel Spider Solifugae Camel spiders are neither spiders nor scorpions but a separate arachnid order. They have no venom and do not chase people, but their jaws are among the largest of any animal for their size. Read the guide →
Birds VU Campbell Albatross Thalassarche impavida The Campbell albatross breeds only on a single New Zealand island and is one of the only albatross species with a pale golden-yellow eye instead of the dark iris typical of most mollymawks. Read the guide →
Birds NT Campbell Shag Leucocarbo campbelli The Campbell shag breeds only around New Zealand's Campbell Island, one of several closely related blue-eyed shag species that each occupy their own single subantarctic island group. Read the guide →
Mammals LC Campbell's Dwarf Hamster Phodopus campbelli Campbell's dwarf hamster is a small, striped steppe hamster of Mongolia and southern Siberia, so similar to the Djungarian hamster that the two are often confused. Read the guide →
Birds LC Canada Goose Branta canadensis The Canada goose migrates in noisy V-formations, but many populations no longer migrate at all — they have settled year-round on lawns, golf courses, and city parks across North America and Europe. Read the guide →
Mammals LC Canada Lynx Lynx canadensis The Canada lynx depends so heavily on snowshoe hares that its own population rises and falls tracking hare abundance, an oversized-pawed predator built specifically to hunt across deep boreal snow. Read the guide →
Birds NT Canada Warbler Cardellina canadensis The Canada warbler is one of the last warblers to arrive each spring and one of the first to leave each fall, packing its entire breeding season into an unusually short window each year. Read the guide →
Amphibians LC Canadian Toad Anaxyrus hemiophrys The Canadian toad ranges further north than any other North American toad species, tolerating long, cold prairie winters and carrying a distinctive bony ridge between its eyes. Read the guide →
Fish NE Candiru Vandellia cirrhosa The candiru is a tiny, translucent Amazonian catfish that darts into the gills of larger fish, hooks in with backward spines, and drinks blood. Its reputation for entering humans is mostly a myth. Read the guide →
Fish EN Candy Darter Etheostoma osburni The candy darter shows some of the most vivid coloring of any North American freshwater fish, and hybridization with an introduced relative threatens to erase its genetics. Read the guide →
Amphibians LC Cane Toad Rhinella marina The cane toad was released in Australia in 1935 to eat beetles and became one of the worst invasive species in the world. Learn why it is toxic, how far it has spread, and what is being done. Read the guide →
Invertebrates LC Cannonball Jellyfish Stomolophus meleagris The cannonball jellyfish trades long stinging tentacles for a smooth, round bell and a mild sting, and it is harvested by the ton and hunted by leatherback sea turtles in equal measure. Read the guide →
Reptiles LC Canyon Lizard Sceloporus merriami The canyon lizard clings flat against sun-baked rock in desert canyons, its small body and pale colouration blending so well with limestone and rhyolite that it can be nearly invisible. Read the guide →
Amphibians LC Canyon Treefrog Hyla arenicolor The canyon treefrog matches the colour of the rock it sits on, a desert amphibian so effectively camouflaged against sandstone and granite it can be nearly invisible up close. Read the guide →
Birds LC Canyon Wren Catherpes mexicanus The canyon wren's cascading, descending song echoes distinctively off canyon walls, a sound so tied to its rocky habitat that the bird itself is often heard long before it's ever seen. Read the guide →
Mammals CR Cao Vit Gibbon Nomascus nasutus The Cao Vit gibbon is a Critically Endangered ape of limestone forest on the Vietnam-China border, rediscovered in 2002 after being feared extinct, with only about a hundred animals left. Read the guide →
Reptiles LC Cape Cobra Naja nivea The Cape cobra is a hooded, golden to copper-coloured cobra of southern Africa's dry scrub and fynbos, with a highly neurotoxic venom, that hunts by day and often enters farm buildings for rodents. Read the guide →
Mammals LC Cape Elephant Shrew Elephantulus edwardii The Cape elephant shrew is found only within a corner of South Africa's fynbos and rocky uplands, patrolling a network of trails through vegetation found nowhere else in the world. Read the guide →
Mammals LC Cape Grey Mongoose Herpestes pulverulentus The Cape grey mongoose is one of southern Africa's smallest solitary mongoose species, a grizzled, secretive hunter of scrubland and fynbos rarely seen far from cover. Read the guide →
Mammals LC Cape Ground Squirrel Xerus inauris The Cape ground squirrel holds its own bushy tail up like a parasol for shade, a highly social burrowing rodent of southern Africa's hottest, driest terrain. Read the guide →
Mammals LC Cape Mole-rat Georychus capensis The Cape mole-rat is a solitary South African digger that lives almost entirely underground and sends messages to neighbours by drumming its hind feet on the tunnel floor. Read the guide →
Birds LC Cape Petrel Daption capense The Cape petrel has a bold, checkered black-and-white pattern across its wings and back, making it one of the most visually distinctive and easily recognised seabirds of the Southern Ocean. Read the guide →
Fish LC Capelin Mallotus villosus Capelin spawn in numbers so enormous that beaches in Newfoundland and Iceland turn silver with rolling fish, a spectacle that also feeds nearly every major predator in the North Atlantic. Read the guide →
Birds LC Capuchinbird Perissocephalus tricolor The capuchinbird is a large Amazonian cotinga with a bare blue head like a monk's cowl. Males gather at treetop leks and give a bizarre call that sounds like a distant mooing cow or a chainsaw. Read the guide →
Mammals LC Capybara Hydrochoerus hydrochaeris The capybara is the world's largest rodent — a 50-kilogram, semi-aquatic grazer famous for its calm tolerance of almost every other animal. Learn how it lives in the wetlands of South America. Read the guide →
Mammals LC Caracal Caracal caracal The caracal is a medium-sized wild cat with tufted black ears and the highest vertical leap of any cat — able to spring nearly three metres straight up to knock birds out of the air. Read the guide →
Fish LC Cardinal Tetra Paracheirodon axelrodi The cardinal tetra carries a brilliant blue-red stripe running the entire length of its body, a small schooling fish from the Amazon's blackwater rivers popular in home aquariums worldwide. Read the guide →
Fish LC Cardinalfish Apogonidae The cardinalfish family includes hundreds of mostly nocturnal reef species, many of them mouthbrooders in which the male carries a mouthful of eggs until they hatch. Read the guide →
Invertebrates LC Carolina Mantis Stagmomantis carolina The Carolina mantis is one of the few praying mantises actually native to North America, smaller and less often noticed than the larger introduced species that share its gardens. Read the guide →
Fish VU Carolina Pygmy Sunfish Elassoma boehlkei The Carolina pygmy sunfish is known from only a small number of blackwater streams along the Carolina coastal plain, a tiny, rarely seen fish confined to a narrow strip of vegetated wetland habitat. Read the guide →
Fish VU Carp Cyprinus carpio A carp is a hardy freshwater fish that roots through mud, shrugs off water that would kill most fish, and has been farmed for thousands of years while wrecking wetlands where it is introduced. Read the guide →
Invertebrates LC Carpenter Ant Camponotus The carpenter ant excavates smooth galleries through wood rather than eating it, and one specialized soldier caste can rupture its own body to spray a sticky, toxic defensive secretion at attackers. Read the guide →
Invertebrates LC Carpenter Bee Xylocopa The carpenter bee drills a near-perfectly round tunnel straight into solid wood using its own jaws, and a male will aggressively hover near the entrance despite being physically unable to sting. Read the guide →
Amphibians LC Carpenter Frog Lithobates virgatipes The carpenter frog of the US Atlantic coast is named for a call like carpenters hammering nails, and it is one of the few frogs that breeds in the harsh acid water of a sphagnum bog. Read the guide →
Invertebrates NE Carpet Anemone Stichodactyla and relatives The carpet anemone spreads a broad, flattened disc covered in short tentacles across the reef floor, among the most powerfully stinging anemones a diver can encounter. Read the guide →
Reptiles LC Carpet Chameleon Furcifer lateralis The carpet chameleon lives fast even by chameleon standards, reaching sexual maturity within months, a survival strategy for a small Madagascar species with a naturally short lifespan. Read the guide →
Reptiles LC Carpet Python Morelia spilota A carpet python is a medium-sized, non-venomous Australian constrictor with a bold gold-and-brown pattern, at home in trees and roof spaces, and a widely kept pet valued for its calm nature. Read the guide →
Birds LC Carunculated Caracara Phalcoboenus carunculatus The carunculated caracara is identified by fleshy orange-red facial caruncles, foraging across high Andean grassland further north than its Patagonian relatives. Read the guide →
Amphibians VU Cascade Caverns Salamander Eurycea latitans The Cascade Caverns salamander lives entirely within cave streams and springs of the Texas Hill Country, sometimes retaining tiny remnants of eyes despite spending its whole life in total darkness. Read the guide →
Amphibians NT Cascade Torrent Salamander Rhyacotriton cascadae The Cascade torrent salamander is the last of four species split from a single wide-ranging ancestor, surviving only in the coldest streams of the Washington Cascades. Read the guide →
Amphibians NT Cascades Frog Rana cascadae A Cascades frog is a mountain frog of the Pacific Northwest that breeds in meltwater pools at the snow line, and it has vanished from the south of its range as stocked trout and disease moved in. Read the guide →
Birds LC Caspian Tern Hydroprogne caspia The Caspian tern is the largest tern in the world, armed with a massive, blood-red bill powerful enough to seize fish that would challenge much smaller tern species entirely. Read the guide →
Birds LC Cassowary Casuarius A cassowary is a huge flightless rainforest bird often called the world's most dangerous, for the dagger claw on each inner toe, and a key disperser of the biggest rainforest seeds. Read the guide →
Birds LC Catbird Dumetella carolinensis A catbird is a slim, slate-grey American songbird named for its cat-like mewing call, a mimid relative of the mockingbird that is one of the few birds able to reliably reject a cowbird's egg. Read the guide →
Invertebrates NE Caterpillar Lepidoptera A caterpillar is the larva of a butterfly or moth, an eating machine that can multiply its weight thousands of times, moults its skin several times, and then dissolves itself inside a pupa. Read the guide →
Fish NE Catfish Siluriformes A catfish is one of a vast group of mostly bottom-living, scaleless fish that carry whiskery barbels, taste with their whole skin, and defend themselves with sharp locking fin spines. Read the guide →
Birds LC Cattle Egret Bubulcus ibis The cattle egret is a small white heron that followed grazing herds out of Africa, crossed the Atlantic on its own around 1877, and now trails cattle and tractors across most of the world. Read the guide →
Mammals LC Cave Nectar Bat Eonycteris spelaea The cave nectar bat is a Southeast Asian nectar-feeding bat that roosts in huge cave colonies and pollinates durian and other tropical fruit trees on its nightly flights. Read the guide →
Amphibians LC Cave Salamander Eurycea lucifuga The cave salamander is a bright orange, long-tailed climber living at the edge of cave systems, gripping rock walls with a prehensile tail most salamanders lack. It never leaves the twilight zone. Read the guide →
Invertebrates LC Cecropia Moth Hyalophora cecropia The cecropia moth is the largest native moth in North America, and its adult stage has no working mouthparts at all — it lives about a week on stored fat, existing purely to find a mate before dying. Read the guide →
Birds LC Cedar Waxwing Bombycilla cedrorum The cedar waxwing is a sleek, crested songbird with waxy red tips on its wing feathers. Flocks sometimes become visibly intoxicated after eating overripe, fermented berries. Read the guide →
Fish LC Celebes Rainbowfish Marosatherina ladigesi The celebes rainbowfish carries unusually elongated, flag-like fins for its small size, native to a limited area of Sulawesi, Indonesia, and distinct enough to sit in its own genus. Read the guide →
Fish LC Celestial Pearl Danio Danio margaritatus The celestial pearl danio was unknown to science until 2006, and within months of its discovery a tiny, star-speckled fish barely two centimetres long had become a global aquarium sensation. Read the guide →
Invertebrates NE Centipede Chilopoda A centipede is a fast, flattened predator with one pair of legs per body segment and a pair of venom claws under the head, and despite the name no centipede has exactly one hundred legs. Read the guide →
Reptiles LC Central Bearded Dragon Pogona vitticeps The central bearded dragon is an Australian desert lizard that puffs a spiky black "beard" to threaten rivals, waves one arm to signal submission, and has become one of the world's top pet reptiles. Read the guide →
Fish LC Central Stoneroller Campostoma anomalum The central stoneroller grazes algae off rocks using a hard ridge on its lower jaw, and a breeding male develops a crown of large, sharp head tubercles used to battle rivals for spawning territory. Read the guide →
Birds NT Cerulean Warbler Setophaga cerulea The cerulean warbler has declined faster than almost any other North American warbler, tied to the loss of both the tall forest canopy it breeds in and the shaded coffee plantations it winters in. Read the guide →
Mammals LC Chacma Baboon Papio ursinus The chacma baboon ranges further south than any other baboon species, its long-studied troops helping researchers understand primate social intelligence. Read the guide →
Birds EN Chaco Eagle Buteogallus coronatus The chaco eagle is one of South America's most threatened raptors, hunting armadillos and reptiles across the open woodland of the Gran Chaco and Argentine pampas. Read the guide →
Reptiles VU Chaco Tortoise Chelonoidis chilensis The Chaco tortoise burrows underground to escape both the scorching heat of summer and the freezing cold of winter across the dry grassland and scrubland of Argentina. Read the guide →
Amphibians LC Chacoan Horned Frog Ceratophrys cranwelli The Chacoan horned frog is nearly all mouth, an ambush predator that buries itself in soil with only its eyes exposed and strikes at anything that moves close enough, regardless of size. Read the guide →
Fish LC Chain Pickerel Esox niger The chain pickerel is the small pike of eastern North America, a slim green ambush fish marked with a dark chain-link pattern that explodes from weed cover onto passing prey. Read the guide →
Birds LC Chalk-browed Mockingbird Mimus saturninus The chalk-browed mockingbird mimics the songs of other bird species with remarkable accuracy, a bold and vocal presence across open habitat throughout central South America. Read the guide →
Invertebrates LC Chambered Nautilus Nautilus pompilius The chambered nautilus is a shelled relative of the octopus and squid whose body plan has survived roughly 500 million years. It jets backward, has up to 90 tentacles, and pinhole eyes with no lens. Read the guide →
Amphibians LC Chamberlain's Dwarf Salamander Eurycea chamberlaini Chamberlain's dwarf salamander was only recognized as its own species after genetic study split it away from the wider dwarf salamander group it had long been lumped into. Read the guide →
Reptiles NE Chameleon Chamaeleonidae A chameleon is a tree lizard that grips branches with pincer feet, aims each eye on its own, fires a spring-loaded tongue longer than its body, and changes colour mainly to signal mood. Read the guide →
Mammals LC Chamois Rupicapra rupicapra The chamois can leap nearly two metres straight up and sprint down steep alpine slopes at speed, a European mountain goat-antelope whose hide gave chamois leather its name. Read the guide →
Fish LC Channel Catfish Ictalurus punctatus The channel catfish is the most fished-for and most farmed catfish in the United States, a whiskered, scaleless fish that tastes the world with its entire skin and finds food in total darkness. Read the guide →
Amphibians LC Channel Islands Slender Salamander Batrachoseps pacificus The Channel Islands slender salamander survives on a handful of islands off southern California, an eel-like, lungless amphibian that reached its island home long before humans ever set foot there. Read the guide →
Birds LC Channel-billed Toucan Ramphastos vitellinus The channel-billed toucan carries a bold black bill with a pale, channel-like ridge running along its base, a large fruit-eating bird whose deep croaking call carries far across the Amazon canopy. Read the guide →
Birds VU Chatham Albatross Thalassarche eremita The Chatham albatross breeds nowhere on Earth except a single rock stack in New Zealand's Chatham Islands, concentrating its entire world population onto one small site. Read the guide →
Birds VU Chatham Petrel Pterodroma axillaris The Chatham petrel breeds only on a single Chatham Islands island, where returning birds must compete with broad-billed prions already nesting in the same burrows. Read the guide →
Birds EN Chatham Shag Leucocarbo onslowi The Chatham shag breeds only on New Zealand's Chatham Islands, one of the rarer blue-eyed shag species and among the small-ranged cormorant relatives most exposed to localised threats. Read the guide →
Amphibians LC Chattahoochee Slimy Salamander Plethodon chattahoochee The Chattahoochee slimy salamander occupies its own corner of the southern Appalachians, one of more than a dozen distinct species revealed when the old slimy salamander complex was split apart. Read the guide →
Amphibians VU Cheat Mountain Salamander Plethodon nettingi The Cheat Mountain salamander survives on a handful of high ridges in West Virginia, a lungless amphibian so narrowly restricted its entire range fits within a few isolated mountaintops. Read the guide →
Birds LC Checker-Throated Antwren Epinecrophylla fulviventris The checker-throated antwren is a dead-leaf specialist, manipulating curled, suspended dead leaves in the understorey to find insects most other birds never think to look for. Read the guide →
Mammals LC Checkered Elephant Shrew Rhynchocyon cirnei The checkered elephant shrew wears a mottled, checkerboard-like pattern across its back, camouflage that helps it blend into the dappled light of the Central African forest floor. Read the guide →
Reptiles LC Checkered Garter Snake Thamnophis marcianus The checkered garter snake tolerates heat and drought better than most of its garter snake relatives, surviving comfortably in arid habitat that would leave many close relatives struggling. Read the guide →
Reptiles LC Checkered Whiptail Aspidoscelis tesselata The checkered whiptail exists entirely as an all-female species that reproduces by parthenogenesis, its origin traced to a single ancient hybridization event between two separate whiptail species. Read the guide →
Birds VU Cheer Pheasant Catreus wallichii The cheer pheasant announces its territory with loud, distinctive calls at dawn and dusk, a habit that has made this Vulnerable Himalayan bird easier to survey by ear than by sight. Read the guide →
Mammals VU Cheetah Acinonyx jubatus The cheetah is the fastest land animal, built entirely for the sprint. Learn how it hits 100 km/h, why the chase costs so much, and why only about 6,500 remain in the wild. Read the guide →
Amphibians LC Cheoah Bald Salamander Plethodon cheoah The Cheoah Bald salamander is confined to a single high-elevation stretch of the southern Appalachians, one of the most narrowly distributed woodland salamanders in North America. Read the guide →
Invertebrates NE Cherry Shrimp Neocaridina davidi The cherry shrimp has been selectively bred into a deep, solid red colour from a naturally plainer wild form, now one of the most popular small shrimp kept in freshwater aquariums. Read the guide →
Birds LC Chestnut-Crowned Antpitta Grallaria ruficapilla Some chestnut-crowned antpittas have been trained to visit feeding stations for worms, offering rare close views of an otherwise painfully shy family. Read the guide →
Birds LC Chestnut-mandibled Toucan Ramphastos ambiguus The chestnut-mandibled toucan is one of the largest toucans in the world, closely related to the keel-billed toucan but identified by the warm chestnut-brown lower half of its otherwise dark bill. Read the guide →
Birds LC Chestnut-Sided Warbler Setophaga pensylvanica The chestnut-sided warbler was rare before European settlement and only became common after widespread logging created the shrubby, second-growth habitat the species actually prefers. Read the guide →
Birds LC Chestnut-throated Huet-huet Pteroptochos castaneus The chestnut-throated huet-huet forages through the leaf litter of central-southern Chilean forest, identified by the warm chestnut patch on its throat. Read the guide →
Birds LC Chickadee Poecile A chickadee is a small, bold North American woodland bird that caches food by the thousand, grows extra brain cells each autumn to remember where, and codes threat detail into its namesake call. Read the guide →
Reptiles LC Chicken Turtle Deirochelys reticularia The chicken turtle carries a neck nearly as long as its own shell, and in parts of its range it nests in autumn rather than spring, an unusual reversal among turtles. Read the guide →
Mammals NT Chilean Dolphin Cephalorhynchus eutropia The Chilean dolphin is one of the smallest dolphin species in the world, found only in the coastal waters of Chile, where it favours shallow bays, fjords, and river mouths close to shore. Read the guide →
Birds NT Chilean Flamingo Phoenicopterus chilensis The Chilean flamingo is the southernmost breeding flamingo species in the world, filtering tiny crustaceans and algae from soda lakes and coastal lagoons across southern South America. Read the guide →
Birds LC Chilean Flicker Colaptes pitius The Chilean flicker forages for ants on open ground rather than climbing tree trunks, an unusual habit among woodpeckers found across the open woodland and scrubland of Chile and Argentina. Read the guide →
Birds NT Chilean Pigeon Patagioenas araucana The Chilean pigeon depends heavily on the fruit of the Chilean wine palm and native southern beech trees, its populations declining alongside the temperate rainforest it calls home. Read the guide →
Invertebrates LC Chilean Recluse Spider Loxosceles laeta The Chilean recluse spider carries one of the most medically significant venoms of any spider species, capable of causing severe tissue damage in rare bite cases. Read the guide →
Invertebrates LC Chilean Rose Tarantula Grammostola rosea The Chilean rose tarantula is one of the most popular pet tarantulas in the world thanks to its calm temperament, with females capable of living for two decades or more. Read the guide →
Birds LC Chilean Skua Stercorarius chilensis The Chilean skua has distinctive warm cinnamon-toned underparts unlike any other skua species, breeding along the coasts of southern Chile and Argentina before migrating north for the winter. Read the guide →
Invertebrates LC Chilean Stag Beetle Chiasognathus grantii Male Chilean stag beetles carry enormous mandibles longer than their own body, wielded in ritualised combat with rivals and first described to science by Charles Darwin himself. Read the guide →
Birds LC Chilean Swallow Tachycineta meyeni The Chilean swallow migrates seasonally across southern South America, nesting in tree cavities and abandoned woodpecker holes rather than building a nest from scratch. Read the guide →
Birds LC Chilean Tinamou Nothoprocta perdicaria The Chilean tinamou relies on strong legs and a weak, reluctant flight to escape danger, spending nearly all of its time on the ground across central Chile's grassland and scrubland. Read the guide →
Fish LC Chili Rasbora Boraras brigittae The chili rasbora is barely two centimetres long yet burns with an intense red colour, one of the smallest schooling fish kept in aquariums and a favourite for tiny nano tanks. Read the guide →
Birds LC Chiloe Wigeon Mareca sibilatrix The Chiloe wigeon grazes on grass like a goose more than it dabbles like a typical duck, sporting a metallic green head patch unlike the rufous heads of most other wigeon species. Read the guide →
Fish LC Chimaera Chimaeriformes The chimaera split from the shark lineage some 400 million years ago, a smooth-skinned, cartilaginous deep-sea fish with tooth plates instead of individual teeth and a venomous spine for defence. Read the guide →
Birds LC Chimango Caracara Milvago chimango The chimango caracara is an adaptable scavenger and opportunist of southern South America, thriving equally well in wild grassland, farmland, and urban areas, feeding on almost anything it can find. Read the guide →
Birds VU Chimney Swift Chaetura pelagica The chimney swift nests and roosts almost entirely inside chimneys today, a species declining steeply as old, uncapped chimneys disappear from the landscape. Read the guide →
Mammals EN Chimpanzee Pan troglodytes The chimpanzee is one of our two closest living relatives, sharing about 98.8% of our DNA. Learn how chimp societies work, how they use tools and hunt, and why they're Endangered. Read the guide →
Mammals EN Chinchilla Chinchilla lanigera The chinchilla has the densest fur of any land mammal — up to 60 hairs per follicle — which nearly caused its extinction. It bathes in volcanic dust and lives on cold, barren Andean slopes. Read the guide →
Reptiles CR Chinese Alligator Alligator sinensis The Chinese alligator is one of the smallest and rarest crocodilians — a 1.5-metre, burrow-digging, cold-tolerant alligator down to perhaps 150 wild adults in a few ponds in eastern China. Read the guide →
Reptiles EN Chinese Crocodile Lizard Shinisaurus crocodilurus The Chinese crocodile lizard is a semi-aquatic lizard named for the raised, bony-looking scales down its tail. It hunts in cool forest streams and is the only surviving species of an ancient family. Read the guide →
Mammals LC Chinese Ferret-Badger Melogale moschata The Chinese ferret-badger tolerates disturbed farmland and village edges as readily as forest, a small, adaptable Asian carnivore identified by bold facial markings. Read the guide →
Amphibians NT Chinese Fire-belly Newt Cynops orientalis The Chinese fire-belly newt is a small black newt with an orange-blotched belly it flashes as a warning. Its skin holds tetrodotoxin, and it is one of the most heavily traded amphibians in the world. Read the guide →
Amphibians CR Chinese Giant Salamander Andrias davidianus The Chinese giant salamander is the largest amphibian on Earth, reaching 1.8 m, and a survivor of a lineage 170 million years old. Farming and hunting have all but wiped it from the wild. Read the guide →
Mammals LC Chinese Hamster Cricetulus griseus The Chinese hamster is a slender, long-tailed hamster of northern China and Mongolia whose cells became one of the most important tools in modern medicine and biotechnology. Read the guide →
Invertebrates LC Chinese Mantis Tenodera sinensis The Chinese mantis is the largest mantis in North America, an East Asian species introduced in the 1890s that hunts across gardens and is big enough to snatch a hummingbird from a feeder. Read the guide →
Mammals CR Chinese Pangolin Manis pentadactyla The Chinese pangolin is a Critically Endangered, scaly anteater that curls into an armoured ball, digs deep burrows, and is among the world's most trafficked mammals. Read the guide →
Reptiles VU Chinese Water Dragon Physignathus cocincinus A Chinese water dragon is a green, long-tailed lizard of Southeast Asian streams that dives and swims to escape danger, has a light-sensing third eye on its head, and is a popular but demanding pet. Read the guide →
Fish LC Chinook Salmon Oncorhynchus tshawytscha The Chinook is the largest Pacific salmon, a fish that carries ocean nutrients far inland and feeds bears, eagles, and orcas, and whose river runs are among the most dammed in North America. Read the guide →
Birds LC Chinstrap Penguin Pygoscelis antarcticus The chinstrap penguin has a thin black band running beneath its chin, resembling a helmet strap, and forms some of the largest and loudest penguin colonies in the Southern Ocean. Read the guide →
Birds LC Chipping Sparrow Spizella passerina The chipping sparrow lines its nest almost exclusively with animal hair, historically horsehair, and will still travel considerable distances to find a suitable source if none is close by. Read the guide →
Amphibians VU Chiricahua Leopard Frog Lithobates chiricahuensis The Chiricahua leopard frog survives in isolated pools scattered across southwestern sky-island mountains, a federally threatened species also facing a lethal amphibian fungus. Read the guide →
Mammals LC Chital Axis axis The chital keeps its bright white spots for life, an Indian deer that often forages beneath troops of langur monkeys, relying on the primates' sharper eyesight to warn of approaching tigers. Read the guide →
Invertebrates LC Chiton Polyplacophora A chiton is an armoured mollusk covered in eight overlapping shell plates, and its teeth are reinforced with one of the hardest biological materials ever measured, harder than human tooth enamel. Read the guide →
Invertebrates NE Chocolate Chip Sea Star Protoreaster nodosus The chocolate chip sea star carries rows of dark, cone-shaped bumps across a pale body that make it look edible, a slow, armoured seafloor predator popular in the aquarium trade for that resemblance. Read the guide →
Fish VU Chocolate Gourami Sphaerichthys osphromenoides The chocolate gourami is a shy, small-bodied labyrinth fish of Southeast Asian blackwater swamps that carries its eggs and young inside its mouth rather than building a bubble nest. Read the guide →
Birds LC Chocolate-backed Kingfisher Halcyon badia The chocolate-backed kingfisher spends its life deep within African rainforest, so secretive that its rich, warm-brown back is more often described from museum specimens than from live sightings. Read the guide →
Amphibians LC Chorus Frog Pseudacris A chorus frog is a small striped North American frog whose spring call sounds like a finger run down the teeth of a stiff comb, multiplied by hundreds of males in a flooded field. Read the guide →
Fish LC Christmas Darter Etheostoma hopkinsi The Christmas darter's breeding males flash festive red and green bands along the body, a combination bright enough to have given this small Southeastern fish its holiday-themed common name. Read the guide →
Invertebrates LC Christmas Island Red Crab Gecarcoidea natalis Around 50 million red crabs live in Christmas Island's rainforest, and once a year the first wet-season rains send them marching to the sea to breed — closing roads and covering beaches red. Read the guide →
Invertebrates NE Christmas Tree Worm Spirobranchus giganteus The Christmas tree worm spends its whole adult life anchored inside living coral, showing only two brightly coloured spiral crowns that filter food and vanish in a flash at the first shadow. Read the guide →
Fish LC Chub Squalius cephalus The chub is a wary, thick-bodied river fish with a broad head and big mouth that eats almost anything, from insects and crayfish to small fish and berries that fall into the water. Read the guide →
Birds LC Chucao Tapaculo Scelorchilus rubecula The chucao tapaculo is a loud, ground-dwelling bird of southern beech forest that rarely flies, more often heard through its explosive call than actually seen scurrying through dense undergrowth. Read the guide →
Reptiles LC Chuckwalla Sauromalus ater The chuckwalla is a chunky desert lizard that escapes predators by wedging into a rock crack and gulping air until it cannot be pulled out. It is a strict vegetarian that never drinks water. Read the guide →
Birds LC Chukar Partridge Alectoris chukar The chukar partridge has been introduced so successfully to rocky, arid terrain worldwide that hunters in places as far apart as Hawaii and Nevada now consider it a familiar local game bird. Read the guide →
Fish LC Chum Salmon Oncorhynchus keta The chum salmon develops dramatic canine-like teeth during spawning season, earning it the nickname dog salmon, and undertakes one of the widest-ranging migrations of any Pacific salmon species. Read the guide →
Invertebrates NE Cicada Cicadidae A cicada is a loud sap-feeding insect whose males make the shrill summer drone with a pair of drumhead organs, and whose young spend years underground before emerging to breed and die within weeks. Read the guide →
Invertebrates NE Cicada Killer Sphecius speciosus The eastern cicada killer is a wasp as long as a thumb that looks frightening but almost never stings people, the female stocking her burrow with paralysed cicadas. Read the guide →
Fish NE Cichlid Cichlidae A cichlid is a freshwater fish of a huge, fast-evolving family famous for elaborate parental care, mouthbrooding, and explosive bursts of new species in the African Great Lakes. Read the guide →
Birds LC Cinereous Harrier Circus cinereus The cinereous harrier hunts by flying low over Patagonian marshes and grassland, males pale grey and females a streaked brown, a difference typical of harriers worldwide. Read the guide →
Invertebrates NE Cinnabar Moth Tyria jacobaeae The cinnabar moth is a black-and-crimson, day-flying moth whose orange-and-black banded caterpillars eat poisonous ragwort and store its toxins, and which has been used to control ragwort overseas. Read the guide →
Birds LC Cinnamon Becard Pachyramphus cinnamomeus The cinnamon becard shows warm cinnamon-brown plumage throughout, building a large, globular hanging nest in lowland Neotropical forest. Read the guide →
Birds LC Cinnamon Teal Spatula cyanoptera The cinnamon teal male displays some of the deepest, most saturated red-brown plumage of any North American duck, a colour so intense that it can appear almost glowing in strong sunlight. Read the guide →
Mammals LC Civet Viverridae A civet is a small, nocturnal, cat-like carnivore of Africa and Asia, valued for its musky scent-gland secretion in perfume and, controversially, for coffee its Asian relative partly digests. Read the guide →
Invertebrates LC Clam Shrimp Spinicaudata A clam shrimp is a small crustacean enclosed within a hinged, two-part shell that makes it look almost exactly like a tiny clam, though the two animals are not closely related at all. Read the guide →
Birds LC Clapper Rail Rallus crepitans The clapper rail thrives in salt marsh where few other rails can survive, its harsh clattering call carrying across the exposed, tidal grasslands it calls home along the Atlantic and Gulf coasts. Read the guide →
Birds LC Clark's Nutcracker Nucifraga columbiana Clark's nutcracker is a mountain crow that buries tens of thousands of pine seeds each autumn and remembers where, and the whitebark pine now depends on it to plant the next forest. Read the guide →
Reptiles LC Clark's Spiny Lizard Sceloporus clarkii Clark's spiny lizard is a genuinely capable climber, spending far more time in trees than most of its ground-dwelling spiny lizard relatives. Read the guide →
Amphibians NE Clawed Frog Pipidae A clawed frog is a flat, fully aquatic frog with no tongue and small black claws on its hind feet, and the African clawed frog is one of the most studied animals in biology and a widespread invader. Read the guide →
Invertebrates LC Cleaner Shrimp Lysmata A cleaner shrimp runs a parasite-removal station on the reef, waving its antennae to advertise, and fish line up to have it pick dead skin and parasites from their bodies and open mouths. Read the guide →
Fish LC Cleaner Wrasse Labroides dimidiatus The cleaner wrasse runs a service station on the reef, picking parasites and dead skin off other fish that queue up for it. It passed the mirror mark test, a result once thought to be beyond fish. Read the guide →
Invertebrates LC Click Beetle Elateridae The click beetle flips itself upright with a sudden spring-loaded snap when stuck on its back, launching into the air with an audible click, a mechanism some tropical species also use to glow. Read the guide →
Amphibians LC Cliff Chirping Frog Eleutherodactylus marnockii The cliff chirping frog skips the tadpole stage entirely, hatching from eggs laid in limestone crevices directly into miniature froglets, a genuinely rare life history among North American amphibians. Read the guide →
Birds LC Cliff Swallow Petrochelidon pyrrhonota The cliff swallow builds an enclosed, gourd-shaped nest from mud pellets, packing hundreds of beakfuls onto a cliff face or bridge to construct a structure unlike any other North American bird's nest. Read the guide →
Fish LC Climbing Perch Anabas testudineus The climbing perch breathes air, survives days on land, and lurches overland on its gill covers to reach new pools. In Australia it is feared as an invader that chokes the predators that eat it. Read the guide →
Invertebrates NE Clothes Moth Tineola bisselliella The adult clothes moth cannot eat and never damages fabric; every hole chewed into a sweater is the work of its light-avoiding larva, which feeds exclusively on keratin from wool, fur, and feathers. Read the guide →
Mammals VU Clouded Leopard Neofelis nebulosa The clouded leopard has the longest canine teeth relative to skull size of any living cat — like a modern sabre-tooth — and can climb down trees head-first and hang from a branch by one hind foot. Read the guide →
Amphibians LC Clouded Salamander Aneides ferreus The clouded salamander climbs trees and rotting logs with an ease unusual among salamanders, using enlarged toe tips and a strong grip to move through coastal Pacific Northwest forests. Read the guide →
Invertebrates LC Clouded Sulphur Colias philodice The clouded sulphur is one of the most commonly seen butterflies across North America, gathering by the dozens at mud puddles and roadside clover in a behaviour that gives large groups their nickname. Read the guide →
Invertebrates LC Clouded Yellow Colias croceus The clouded yellow is a deep-yellow migratory butterfly that flies north each year from southern Europe and North Africa, in some years arriving in huge numbers in Britain. Read the guide →
Invertebrates LC Cloudless Sulphur Phoebis sennae The cloudless sulphur undertakes a purposeful southward migration each autumn, flying a straight, determined line low over open ground rather than the meandering flight typical of most butterflies. Read the guide →
Invertebrates NE Clown Nudibranch Triopha catalinae The clown nudibranch carries bright orange projections across a pale, translucent body, a colourful bryozoan-eating sea slug found in the cold coastal waters of the northeastern Pacific. Read the guide →
Fish LC Clown Triggerfish Balistoides conspicillum The clown triggerfish pairs a black body covered in large white polka dots with a bold yellow-netted pattern across its back, among the most strikingly patterned fish on any coral reef. Read the guide →
Fish LC Clownfish Amphiprion ocellaris The clownfish lives inside the stinging tentacles of a sea anemone, protected by a special mucus coat. Every clownfish is born male, and the largest in each group turns female. Read the guide →
Birds LC Club-winged Manakin Machaeropterus deliciosus The club-winged manakin is the only bird known to sing with its wings like a cricket, rubbing twisted, thickened feather shafts together over 100 times a second to make a pure violin-like tone. Read the guide →
Mammals LC Clymene Dolphin Stenella clymene The Clymene dolphin was long assumed a form of the spinner dolphin before genetic evidence confirmed it as its own distinct species, performing its own smaller-scale version of the spinning leap. Read the guide →
Reptiles LC Coachwhip Masticophis flagellum The coachwhip is the fastest snake in North America, a slender racer that hunts with its head held high above the grass, and the animal behind the myth that a snake will chase and whip you. Read the guide →
Reptiles LC Coal Skink Plestiodon anthracinus The coal skink carries just two dark stripes rather than the five typical of its close relatives, and it will dive into a stream to escape a predator more readily than most other skinks. Read the guide →
Fish LC Coalfish Pollachius virens The coalfish, or saithe, is a dark-backed, open-water shoaling cod relative of the cold North Atlantic that hunts small fish in schools and is a major food fish across northern Europe. Read the guide →
Reptiles VU Coast Horned Lizard Phrynosoma blainvillii The coast horned lizard has declined sharply across coastal California as the native harvester ants it needs are pushed out by invasive Argentine ants of little nutritional value. Read the guide →
Amphibians LC Coastal Giant Salamander Dicamptodon tenebrosus The coastal giant salamander is North America's largest land salamander, a heavy-bodied predator of Pacific streams that eats mice and snakes — and is one of the few salamanders that can bark. Read the guide →
Reptiles LC Coastal Taipan Oxyuranus scutellatus The coastal taipan is Australia's longest venomous snake and, before antivenom, its most lethal. It strikes prey in a fast flurry, releases it, and tracks it down once the venom takes hold. Read the guide →
Mammals LC Coati Nasua The coati is a long-nosed, ring-tailed raccoon relative that travels in noisy bands of up to 30, tail held straight up like a flag. Its ankles reverse so it can climb down trees head-first. Read the guide →
Invertebrates NE Cobalt Blue Tarantula Cyriopagopus lividus The cobalt blue tarantula shows a vivid metallic blue coloring on its legs, a defensive, fast-moving burrowing spider from Southeast Asia rarely seen out in the open. Read the guide →
Birds NT Cobb's Wren Troglodytes cobbi Cobb's wren survives mainly on rat-free outer islands of the Falklands, foraging along the shoreline for invertebrates left behind by the retreating tide. Read the guide →
Fish LC Cobia Rachycentron canadum The cobia is a large, fast-growing coastal fish often mistaken for a shark or a remora at a distance, and it is the only living species in its entire family, with no close living relatives anywhere. Read the guide →
Reptiles NE Cobra Naja and relatives A cobra is a venomous snake that rears up and spreads a hood of loose neck skin as a warning, and several species can spray venom from the fangs straight at an attacker's eyes. Read the guide →
Birds LC Cockatiel Nymphicus hollandicus The cockatiel roams the outback in loose nomadic flocks like its budgerigar relative, but has become one of the most commonly kept pet parrots worldwide through its calm temperament and whistling. Read the guide →
Invertebrates NE Cockchafer Melolontha melolontha The cockchafer, or May bug, is a large brown beetle with fan-shaped antennae that blunders into lights at dusk, whose white grubs spend three or four years underground eating roots. Read the guide →
Invertebrates LC Cockeyed Squid Histioteuthis heteropsis The cockeyed squid has one large, bulging, upward-facing eye for spotting silhouettes above and one smaller, downward-facing eye for detecting flashes of bioluminescence in the darkness below. Read the guide →
Invertebrates NE Cockroach Blattodea A cockroach is an ancient, flattened, fast-running insect; of about 4,600 species only around 30 live near people, and the rest are harmless recyclers of leaf litter and rotting wood. Read the guide →
Birds LC Cocoi Heron Ardea cocoi The cocoi heron is South America's largest heron, standing motionless at the water's edge before spearing fish with a rapid strike of its long bill. Read the guide →
Invertebrates VU Coconut Crab Birgus latro The coconut crab is the largest land invertebrate on Earth, a 4-kilogram hermit crab relative that climbs trees, husks coconuts with the strongest pinch ever measured, and drowns if held underwater. Read the guide →
Invertebrates NE Coconut Octopus Amphioctopus marginatus The coconut octopus carries empty coconut and clam shells stacked beneath its body, then assembles them into a portable suit of armour — one of the clearest cases of tool use in an invertebrate. Read the guide →
Fish NE Cod Gadidae A cod is a cool-water bottom fish with a chin barbel and a huge appetite, and the Atlantic cod fishery, once thought endless, became the textbook example of a stock fished to collapse. Read the guide →
Fish CR Coelacanth Latimeria chalumnae The coelacanth is a metre-and-a-half deep-sea fish thought extinct for 66 million years until one was caught in 1938. Its lobed, limb-like fins link it to the ancestors of all land vertebrates. Read the guide →
Amphibians LC Coeur d'Alene Salamander Plethodon idahoensis The Coeur d'Alene salamander lives in the spray zone of waterfalls and seeps in the northern Rockies, staying pressed against wet rock where the mist never lets the surface fully dry out. Read the guide →
Fish NT Coho Salmon Oncorhynchus kisutch The coho salmon spends far longer as a freshwater juvenile than most Pacific salmon before heading to sea, and breeding males develop a distinctive hooked jaw. Read the guide →
Invertebrates VU Cold-Water Coral Desmophyllum pertusum Cold-water coral builds enormous reef structures in total darkness without any help from sunlight-loving algae, growing so slowly that a single reef can take centuries to form. Read the guide →
Birds LC Collared Aracari Pteroglossus torquatus The collared aracari is a smaller, highly social relative of the large toucans, marked by a chestnut band across the chest and known for roosting together in tight groups inside a single tree cavity. Read the guide →
Birds LC Collared Dove Streptopelia decaocto The collared dove is a pale sandy pigeon with a black neck ring and a soft three-note coo that spread across Europe in a few decades and then colonised most of North America from a small escape. Read the guide →
Birds LC Collared Kingfisher Todiramphus chloris The collared kingfisher holds one of the widest ranges of any kingfisher, thriving in mangroves, gardens, and coastal towns from the Red Sea to Australia and the Pacific. Read the guide →
Mammals LC Collared Lemming Dicrostonyx groenlandicus The collared lemming turns white in winter and grows enlarged, split winter claws for digging through snow, a rare seasonal change among rodents of the Arctic tundra. Read the guide →
Reptiles LC Collared Lizard Crotaphytus collaris The collared lizard is a bright, big-headed lizard of rocky country in the American Southwest that sprints on its hind legs like a tiny dinosaur and hunts other lizards, including its own kind. Read the guide →
Mammals VU Collared Mongoose Urva semitorquata The collared mongoose carries a pale, collar-like marking around its neck, a rarely observed rainforest species restricted to the islands of Borneo and Sumatra. Read the guide →
Mammals LC Collared Peccary Pecari tajacu The collared peccary travels in tight, cooperative herds that mark each other with scent from a tail gland, a pig-like desert forager that is not actually a true pig despite the striking resemblance. Read the guide →
Mammals LC Collared Pika Ochotona collaris The collared pika spends the short alpine summer racing to gather and dry an enormous hay pile of vegetation, storing enough food beneath the rocks to survive winter without ever hibernating at all. Read the guide →
Birds LC Collared Trogon Trogon collaris The collared trogon sits upright and still for long stretches before making short sallies for insects and fruit, males showing a bright white band across the chest like a collar. Read the guide →
Reptiles VU Colorado Desert Fringe-Toed Lizard Uma notata The Colorado Desert fringe-toed lizard races across loose sand on snowshoe-like fringed toes, then dives beneath the surface to vanish from view entirely. Read the guide →
Invertebrates LC Colorado Potato Beetle Leptinotarsa decemlineata The Colorado potato beetle switched from wild desert plants to cultivated potatoes in the 1800s and has since evolved resistance to nearly every insecticide used against it. Read the guide →
Invertebrates LC Colossal Squid Mesonychoteuthis hamiltoni The colossal squid is the heaviest invertebrate on Earth — up to half a tonne — with the largest eyes of any animal and hooks on its arms. Most of what is known comes from sperm-whale stomachs. Read the guide →
Mammals LC Colugo Galeopterus variegatus The colugo is the champion gliding mammal, sailing 100-plus metres between trees on a membrane reaching its fingertips, toe tips and tail. It is not a lemur and cannot fly. Read the guide →
Amphibians LC Columbia Spotted Frog Rana luteiventris A Columbia spotted frog is a widespread brown frog of the American Northwest and Rockies, tied to permanent water, more terrestrial than its coastal cousin, and hibernating underwater at springs. Read the guide →
Amphibians NT Columbia Torrent Salamander Rhyacotriton kezeri The Columbia torrent salamander lives only in the splash zone of the coldest, cleanest headwater streams, and its presence signals genuinely undisturbed old-growth forest. Read the guide →
Mammals LC Columbian Ground Squirrel Urocitellus columbianus The Columbian ground squirrel is a social meadow squirrel of the northern Rockies region that spends most of the year hibernating and is a key meal for badgers, eagles, and bears. Read the guide →
Amphibians VU Comal Blind Salamander Eurycea tridentifera The Comal blind salamander spends its entire life underground in Texas cave water, with no eyes, no pigment, and external gills it never outgrows. Read the guide →
Amphibians EN Comal Springs Salamander Eurycea sp. The Comal Springs salamander survives entirely within one Texas spring system, spending much of its life deep in the Edwards Aquifer that feeds it. Read the guide →
Birds LC Comb Duck Sarkidiornis sylvicola The comb duck is named for the large fleshy knob breeding males grow atop the bill, one of the most distinctive ornaments of any South American waterfowl. Read the guide →
Invertebrates NE Comb Jelly Pleurobrachia pileus A comb jelly is not a jellyfish but a fragile, transparent ocean drifter that swims with eight rows of beating hair-plates, which scatter light into running rainbows along its body. Read the guide →
Invertebrates NE Comet Moth Argema mittrei The comet moth is a yellow Madagascan silk moth with tails up to 15 centimetres long, one of the longest of any moth, and adults have no mouth and live for only about a week. Read the guide →
Mammals LC Commerson's Dolphin Cephalorhynchus commersonii Commerson's dolphin displays a black-and-white pattern so bold it has earned the nickname skunk dolphin, a small, fast species found in cold coastal waters at the southern tip of South America. Read the guide →
Mammals LC Common Agouti Dasyprocta leporina The common agouti is one of the few animals capable of cracking open a Brazil nut pod, burying extras it can't finish and inadvertently planting new trees. Read the guide →
Reptiles LC Common Basilisk Basiliscus basiliscus The common basilisk of Central America is the original Jesus Christ lizard, able to sprint upright across the surface of a stream on its hind legs for a few metres before it sinks and swims off. Read the guide →
Birds LC Common Blackbird Turdus merula The common blackbird is a European thrush, the glossy black bird with the orange bill that sings from the rooftops at dawn; it is one of the first birds to have fully colonised towns and cities. Read the guide →
Invertebrates LC Common Blue Polyommatus icarus The common blue is a small, widespread butterfly whose males are bright violet-blue and whose brown females are tended by ants, which guard the caterpillars in return for sweet secretions. Read the guide →
Invertebrates LC Common Blue Damselfly Enallagma cyathigerum The common blue damselfly is a bright blue damselfly of lakes and ponds across the Northern Hemisphere, recognised by a mushroom-shaped black mark near the base of the abdomen. Read the guide →
Fish LC Common Bream Abramis brama The common bream is a deep, slab-sided, bronze fish that grubs for worms and snails on the bottom of slow rivers and lakes in large shoals, and is one of the most abundant fish of northern Europe. Read the guide →
Mammals LC Common Brushtail Possum Trichosurus vulpecula The common brushtail possum is Australia's most widespread native marsupial, yet the very same adaptability makes it one of New Zealand's most damaging invasive forest pests. Read the guide →
Invertebrates LC Common Buckeye Junonia coenia The common buckeye carries six enormous false eyespots across its wings, a startling pattern that can flash open in an instant to momentarily confuse or intimidate an approaching predator. Read the guide →
Invertebrates LC Common Carder Bee Bombus pascuorum The common carder bee is a ginger-brown, long-tongued bumblebee of gardens and meadows that nests above ground in grass tussocks and combs moss and grass into a covering for its nest. Read the guide →
Fish VU Common Carp Cyprinus carpio Farmed for two thousand years and bred into koi, the common carp has been released across the world, where its habit of rooting up the bottom makes it one of the most damaging of all invasive fish. Read the guide →
Birds LC Common Chaffinch Fringilla coelebs Common chaffinches sing in distinct regional dialects passed down between generations, a genuine form of cultural learning in one of Europe's commonest birds. Read the guide →
Invertebrates NE Common Cockle Cerastoderma edule The common cockle is a ribbed, heart-shaped bivalve of northeast Atlantic sandflats that filters food from the water, leaps away from predators with its foot, and feeds huge flocks of wading birds. Read the guide →
Birds LC Common Cuckoo Cuculus canorus The common cuckoo lays its eggs in other birds' nests and leaves. The chick hatches first, heaves out the host's eggs, and is raised by foster parents a fraction of its size. Read the guide →
Mammals LC Common Cusimanse Crossarchus obscurus The common cusimanse forages in noisy, highly social groups through West African rainforest, using an elongated snout to root out insects and small prey from the forest floor. Read the guide →
Fish LC Common Dab Limanda limanda The common dab is a small, rough-scaled, right-eyed flatfish of sandy European seas, sandy brown with a strongly arched side line, and one of the most abundant flatfish of the North Sea. Read the guide →
Fish LC Common Dace Leuciscus leuciscus The common dace is a slender, silvery shoaling fish of fast, clear rivers that rises to catch flies at the surface, and is one of the quickest and liveliest of the European carp family. Read the guide →
Invertebrates LC Common Darter Sympetrum striolatum The common darter is a small dragonfly whose male turns orange-red, a late-season species that darts out from a perch to catch prey and is often the last dragonfly on the wing in autumn. Read the guide →
Reptiles LC Common Death Adder Acanthophis antarcticus The common death adder looks and hunts like a viper but is actually an elapid, related to cobras. It lies buried in leaf litter and twitches a grub-like tail tip to lure prey into a lightning strike. Read the guide →
Mammals LC Common Degu Octodon degus The common degu lives in highly social family groups within complex burrow systems, a Chilean rodent valued by scientists for studying circadian rhythms and social behaviour. Read the guide →
Fish VU Common Dentex Dentex dentex The common dentex is a large, deep-bodied, fanged sea bream of Mediterranean and eastern Atlantic reefs that hunts fish and squid, a prized catch of spearfishers and anglers that has been overfished. Read the guide →
Birds LC Common Diuca-finch Diuca diuca The common diuca-finch forages in flocks across open Chilean and Argentine country, its pale grey plumage offering camouflage against dry grassland and scrub. Read the guide →
Birds LC Common Diving-petrel Pelecanoides urinatrix The common diving-petrel flies underwater using its wings to swim in pursuit of prey, then bursts straight out of the waves back into flight without pausing to swim on the surface. Read the guide →
Mammals LC Common Dolphin Delphinus delphis The common dolphin travels in some of the largest dolphin groups in the ocean, sometimes numbering into the thousands, recognisable by a distinctive hourglass pattern of colour along its sides. Read the guide →
Fish LC Common Dragonet Callionymus lyra The common dragonet is a flat-headed sand-dweller of north-eastern Atlantic shallows in which the male is bright blue and yellow with a long dorsal fin, and the female is a drab brown. Read the guide →
Mammals LC Common Duiker Sylvicapra grimmia The common duiker is the most widespread small antelope in Africa, named for the Afrikaans word for "diver" after its habit of ducking into cover the instant it senses danger. Read the guide →
Amphibians LC Common Frog Rana temporaria The common frog is the familiar frog of European gardens and ponds — it can breathe through its skin, survive winter on the bottom of a pond, and returns each year to the pond it hatched in. Read the guide →
Birds LC Common Gallinule Gallinula galeata The common gallinule looks nearly identical to the Old World common moorhen, a resemblance so close the two were treated as a single species until genetic evidence split them apart in 2011. Read the guide →
Reptiles LC Common Garter Snake Thamnophis sirtalis The common garter snake is North America's most widespread snake — a small, striped, mildly venomous hunter that survives Canadian winters by denning in the thousands and can eat toxic newts. Read the guide →
Invertebrates LC Common Green Darner Anax junius The common green darner migrates south in autumn much like a bird, and the generation that returns north the following spring is actually the grandchildren of the ones that made the original journey. Read the guide →
Invertebrates LC Common Green Darner Anax junius The common green darner is one of the fastest, most acrobatic insects and a true migrant — successive generations relay-migrate across North America each year, like monarch butterflies. Read the guide →
Invertebrates NE Common Greenbottle Lucilia sericata The common greenbottle is a metallic green blow fly whose maggots feed on dead flesh, an insect used in forensic science to estimate time of death and in medicine to clean wounds. Read the guide →
Birds LC Common Kingfisher Alcedo atthis The common kingfisher is a jewel-bright riverbank bird that dives head-first into water to spear fish. Read the guide →
Invertebrates NE Common Limpet Patella vulgata The common limpet is the cone-shelled rock-clinger of northeast Atlantic shores, which returns to the same home scar, grazes algae with super-strong teeth, and changes sex as it ages. Read the guide →
Birds LC Common Linnet Linaria cannabina The common linnet takes its name from an old fondness for flax seeds, and has declined sharply across Europe as weedy farmland margins have disappeared. Read the guide →
Birds LC Common Loon Gavia immer The common loon is a heavy-boned diving bird that plunges 60 metres to chase fish, is nearly helpless on land, and fills quiet lakes with a wailing, yodelling call that carries for kilometres. Read the guide →
Mammals LC Common Marmoset Callithrix jacchus The common marmoset is a tiny Brazilian monkey with white ear tufts that gouges trees for sap and gum, usually has twins, and raises its young with the help of the whole family. Read the guide →
Amphibians LC Common Midwife Toad Alytes obstetricans The male common midwife toad carries the fertilised eggs wound around his hind legs for weeks, keeping them moist and safe, and only visits water to release the tadpoles once they are ready to hatch. Read the guide →
Fish LC Common Minnow Phoxinus phoxinus The common minnow is a tiny, shoaling stream fish whose breeding males flush red and black, and whose damaged skin releases an alarm chemical that sends its whole shoal fleeing. Read the guide →
Birds LC Common Moorhen Gallinula chloropus The common moorhen walks confidently across floating vegetation on long, unwebbed toes, a species so similar to its American relative the two were only split apart in 2011. Read the guide →
Reptiles LC Common Musk Turtle Sternotherus odoratus The common musk turtle, or stinkpot, is a tiny bottom-walker that climbs high into streamside trees, sometimes dropping into a boat, and releases a foul musk when it is handled. Read the guide →
Birds LC Common Nighthawk Chordeiles minor The common nighthawk produces a deep, booming sound not with its voice but its wings, pulling out of a steep courtship dive so sharply that air rushing through its feathers creates an audible boom. Read the guide →
Birds LC Common Nightingale Luscinia megarhynchos The common nightingale is a plain brown bird with an extraordinary voice; males sing through the night as well as the day, drawing on a repertoire of around a thousand different sounds. Read the guide →
Invertebrates LC Common Octopus Octopus vulgaris The common octopus has three hearts, blue blood, and two-thirds of its neurons in its arms. Learn how it changes colour in a heartbeat, solves puzzles, and lives just one to two years. Read the guide →
Birds LC Common Pauraque Nyctidromus albicollis The common pauraque is a camouflaged nightjar that lays its eggs directly on bare ground, its eyes glowing bright orange when caught in a flashlight beam at night. Read the guide →
Invertebrates NE Common Periwinkle Littorina littorea The common periwinkle is the dark spiral-shelled winkle of northeast Atlantic shores, a hardy algae-grazer that can survive out of water for days and has spread to the east coast of North America. Read the guide →
Mammals LC Common Pipistrelle Pipistrellus pipistrellus The common pipistrelle is one of Europe's smallest and most widespread bats, a tiny, fast-flying insect hunter that roosts in buildings and can catch thousands of small insects in a night. Read the guide →
Birds LC Common Poorwill Phalaenoptilus nuttallii The common poorwill is a small nightjar of the arid American West and the only bird known to truly hibernate, spending weeks in cold torpor tucked into a rock crevice. Read the guide →
Birds LC Common Potoo Nyctibius griseus The common potoo spends the day frozen upright on a broken stump, invisible against the bark. Slits in its closed eyelids let it watch for danger without opening its eyes. Read the guide →
Invertebrates NE Common Prawn Palaemon serratus The common prawn is a translucent, purple-banded crustacean of rocky European shores that lives in rock pools and kelp, has a toothed, upturned snout, and is eaten across southern Europe. Read the guide →
Birds LC Common Quail Coturnix coturnix The common quail is one of the very few truly migratory quail species, crossing the Mediterranean Sea twice a year despite being a small, weak-flying ground bird. Read the guide →
Birds LC Common Raven Corvus corax The common raven is one of the most intelligent animals on Earth — a large black bird that makes tools, plans for the future, holds grudges, plays in the wind, and solves problems that stump apes. Read the guide →
Birds LC Common Redpoll Acanthis flammea The common redpoll survives Arctic cold down to minus 65 degrees by burrowing into snow to roost and caching seeds in a special throat pouch. Read the guide →
Mammals LC Common Ringtail Possum Pseudocheirus peregrinus The common ringtail possum weaves a spherical nest of leaves called a drey and re-eats its own droppings to fully digest tough eucalyptus leaves. Read the guide →
Birds LC Common Rosefinch Carpodacus erythrinus A male common rosefinch turns a deep raspberry red on the head and breast, singing a simple whistled song often rendered as pleased to meet you. Read the guide →
Invertebrates NE Common Sea Urchin Echinus esculentus The common sea urchin is a round, reddish-purple urchin of northeast Atlantic rocky seas that grazes algae and kelp with its five-toothed Aristotle's lantern and is eaten as a delicacy. Read the guide →
Fish LC Common Shiner Luxilus cornutus The common shiner's breeding males flush a vivid rosy pink along the sides and grow small horn-like bumps on the head, among the most colourful transformations of any widespread North American minnow. Read the guide →
Invertebrates NE Common Shore Crab Carcinus maenas The common shore crab is a hardy greenish-brown crab of European rock pools and estuaries that has spread around the world and is now ranked among the most damaging invasive marine species. Read the guide →
Mammals LC Common Shrew Sorex araneus The common shrew eats almost constantly, needing to consume close to its own body weight in food every day or risk starving to death within a matter of hours. Read the guide →
Reptiles LC Common Snapping Turtle Chelydra serpentina The common snapping turtle is a heavy, long-necked freshwater turtle that is calm underwater but bites hard on land, where its small shell leaves it no way to hide. It can live past 45 years. Read the guide →
Fish LC Common Sole Solea solea The common sole, or Dover sole, is a prized, tongue-shaped flatfish of European sandy seas that buries itself by day, hunts by touch and smell at night, and is one of Europe's most valuable food fish. Read the guide →
Amphibians LC Common Spadefoot Pelobates fuscus The common spadefoot has disappeared from large parts of its former European range as the light, diggable soil and shallow breeding pools it depends on have been lost to intensive farming. Read the guide →
Amphibians LC Common Spadefoot Toad Pelobates fuscus The common spadefoot digs itself backwards into soft soil with a blade-like 'spade' on each hind foot and vanishes in under a minute. Handled, it screams and smells of garlic. Read the guide →
Mammals LC Common Spotted Cuscus Spilocuscus maculatus The common spotted cuscus moves through the rainforest canopy at a deliberate, sloth-like pace, males displaying a mottled coat quite different from the female's plainer fur. Read the guide →
Mammals LC Common Squirrel Monkey Saimiri sciureus The common squirrel monkey lives in some of the largest primate groups on Earth, troops that can number in the hundreds moving together through the canopy. Read the guide →
Invertebrates NE Common Starfish Asterias rubens The common starfish is an orange-brown, five-armed starfish of northeast Atlantic shores that pulls mussels apart with its tube feet and slips its stomach inside the shell to digest them. Read the guide →
Birds LC Common Starling Sturnus vulgaris The common starling is a glossy, spotted songbird famous for its swirling flocks, its talent for mimicry, and its spread across North America from about 100 birds released in New York in the 1890s. Read the guide →
Invertebrates NE Common Stick Insect Carausius morosus The common stick insect is a living twig that reproduces almost entirely without males — lab colonies have run over a century all-female. It sways like a branch and regrows lost legs. Read the guide →
Invertebrates NE Common Sunstar Crossaster papposus The common sunstar is a many-armed, red-orange starfish with rings of colour like a sun that hunts other starfish, sea urchins, and sea cucumbers in the cool waters of the North Atlantic. Read the guide →
Birds LC Common Swift Apus apus The common swift may be the most aerial bird alive. A young swift can stay airborne for two or three years without landing once, and it eats, drinks, sleeps, and mates on the wing. Read the guide →
Mammals LC Common Tenrec Tenrec ecaudatus The common tenrec is the largest living tenrec and has one of the biggest litters of any mammal on Earth, with some females giving birth to more than two dozen young at once. Read the guide →
Birds LC Common Tern Sterna hirundo The common tern hunts by hovering above the water before folding its wings into a sharp plunge dive, a hunting style that has earned terns the nickname "sea swallows" for their agile, buoyant flight. Read the guide →
Fish VU Common Thresher Shark Alopias vulpinus The common thresher shark hunts with its tail — the upper lobe is as long as the rest of the body, and the shark whips it overhead at speed to stun schooling fish before circling back to eat them. Read the guide →
Amphibians LC Common Toad Bufo bufo The common toad is Europe's familiar warty amphibian — a slow, poison-glanded night hunter that returns to its birth pond every spring along the same route, even when a road now runs across it. Read the guide →
Mammals LC Common Vampire Bat Desmodus rotundus The common vampire bat is the only mammal that feeds entirely on blood. It runs and leaps like a spider, shares meals with hungry roost-mates, and its saliva has led to a stroke drug. Read the guide →
Mammals LC Common Vole Microtus arvalis The common vole is a farmland and meadow rodent of continental Europe whose numbers can erupt into outbreaks, and an Orkney population descends from voles carried there by early settlers. Read the guide →
Reptiles LC Common Wall Lizard Podarcis muralis The common wall lizard is the small, flat, quick lizard seen basking on sunny walls and ruins across Europe, and it has founded thriving colonies far outside its range, including one in Ohio. Read the guide →
Mammals LC Common Wallaroo Osphranter robustus The common wallaroo, known locally as the euro, survives in some of Australia's harshest, rockiest terrain by sheltering in caves through the heat of the day. Read the guide →
Mammals LC Common Warthog Phacochoerus africanus The common warthog kneels on padded wrists to graze, sprints at 55 km/h with its tail held straight up, and reverses into an old aardvark burrow so it can face any predator with its tusks. Read the guide →
Invertebrates NE Common Wasp Vespula vulgaris The common wasp is the black-and-yellow wasp of summer picnics, with an anchor-shaped face mark, whose huge paper-nest colonies hunt garden pests before becoming a nuisance in late summer. Read the guide →
Invertebrates LC Common Whitetail Plathemis lydia A mature male common whitetail develops a body so heavily coated in chalky white powder it can look almost artificial, a striking transformation from the brown, patterned dragonfly it started as. Read the guide →
Birds LC Common Yellowthroat Geothlypis trichas The male common yellowthroat wears a bold black mask across the eyes, and females appear to select mates partly based on the size and sharpness of that exact facial marking. Read the guide →
Invertebrates NE Compass Jellyfish Chrysaora hysoscella The compass jellyfish is a pale, translucent jellyfish of the northeast Atlantic whose bell is marked with brown V-shaped lines like a compass, a common sight on European coasts in summer. Read the guide →
Invertebrates VU Conch Strombidae A conch is a large sea snail with a heavy, flared shell and eyes on long, expressive stalks, and its shell has been used as a natural horn and a source of food across the Caribbean for centuries. Read the guide →
Reptiles LC Concho Water Snake Nerodia paucimaculata The Concho water snake exists only along two Texas rivers, and its recovery from federal protection to delisting stands as one of the rarer conservation success stories. Read the guide →
Invertebrates LC Cone Snail Conus geographus The cone snail is a slow predatory sea snail that fires a hollow venom-tipped harpoon; the fish-hunting geographic cone is regarded as the most dangerous snail to humans in the world. Read the guide →
Fish LC Conger Eel Conger conger The conger eel grows into one of the largest true eels in the ocean, a powerful nocturnal hunter that can deliver a hard, provoked bite despite generally staying hidden in a rocky den by day. Read the guide →
Invertebrates LC Convergent Lady Beetle Hippodamia convergens The convergent lady beetle gathers by the millions in mountain overwintering sites, a spectacle so reliable that entire aggregations are commercially collected and sold for garden pest control. Read the guide →
Fish LC Convict Cichlid Amatitlania nigrofasciata The convict cichlid wears bold, vertical black-and-white stripes like a cartoon prisoner, backed by a breeding drive so prolific that a single pair can quickly overwhelm an aquarium with fry. Read the guide →
Fish LC Convict Tang Acanthurus triostegus The convict tang carries bold black vertical stripes across a pale body reminiscent of a prisoner's uniform, and is one of the few surgeonfish species that regularly schools in large numbers. Read the guide →
Invertebrates NE Convolvulus Hawk-moth Agrius convolvuli The convolvulus hawk-moth is a large grey migrant with a pink-banded body and a very long proboscis, which flies north in summer to feed on tobacco plants and other scented flowers at dusk. Read the guide →
Birds VU Cook's Petrel Pterodroma cookii Cook's petrel breeds only on a small number of New Zealand islands, then migrates across the entire Pacific Ocean each year to spend the non-breeding season off the eastern coast of the Americas. Read the guide →
Fish LC Cookiecutter Shark Isistius brasiliensis The cookiecutter shark is a 50 cm deep-sea shark that bites round plugs of flesh out of tuna, whales, seals, and even submarines. It glows to lure large predators close, then latches on and twists. Read the guide →
Birds LC Cooper's Hawk Accipiter cooperii Cooper's hawk has adapted so successfully to suburban life that backyard bird feeders have become a reliable hunting ground, the hawk using the same feeder that draws songbirds as an ambush point. Read the guide →
Amphibians NT Cope's Giant Salamander Dicamptodon copei Cope's giant salamander is the one member of its family that almost never grows up, keeping its feathery larval gills and living permanently in cold streams instead of walking onto land. Read the guide →
Amphibians LC Cope's Gray Treefrog Hyla chrysoscelis Cope's gray treefrog is a warty, colour-changing tree frog of the eastern United States, a look-alike of the common gray treefrog told apart only by its faster call and its chromosome count. Read the guide →
Invertebrates LC Copepod Copepoda Copepods are tiny crustaceans so numerous in the ocean that they are often described as the most abundant multicellular animal group on Earth, forming the base of most marine food webs. Read the guide →
Fish LC Copperband Butterflyfish Chelmon rostratus The copperband butterflyfish carries a false eyespot near its tail and uses a long, narrow snout to pick small invertebrates, including pest anemones, out of tight coral crevices. Read the guide →
Reptiles LC Copperhead Agkistrodon contortrix A copperhead is a coppery, hourglass-banded pit viper of the eastern United States, the cause of more venomous bites there than any other snake but rarely a danger to a healthy adult. Read the guide →
Mammals EN Coquerel's Sifaka Propithecus coquereli Coquerel's sifaka is a white-coated lemur with chestnut patches on its thighs and arms, known for crossing open ground in a distinctive upright, sideways dance-like hop. Read the guide →
Amphibians LC Coqui Eleutherodactylus coqui The coqui is a tiny frog whose two-note night call is the unofficial sound of Puerto Rico, where it is a national symbol; it skips the tadpole stage entirely, which has helped it invade Hawaii. Read the guide →
Invertebrates NE Coral Anthozoa A coral is a colony of tiny animals related to jellyfish, each a soft polyp in a stony cup; reef-builders farm algae in their tissue for food and lay down the largest structures any life has made. Read the guide →
Reptiles NE Coral Snake Micrurus and Micruroides A coral snake is a brightly banded, highly venomous relative of the cobra whose warning colours are copied by several harmless snakes, and which almost never bites people because its fangs are tiny. Read the guide →
Fish LC Corkwing Wrasse Symphodus melops The corkwing wrasse is a small, colourful wrasse of north-eastern Atlantic rocky shores whose breeding male turns blue and green and builds and guards a nest of seaweed in a rock crevice. Read the guide →
Birds LC Cormorant Phalacrocoracidae A cormorant is a dark, long-necked fishing bird that dives and chases fish with its feet, then perches with its wings spread to dry because its feathers are not fully waterproof. Read the guide →
Reptiles LC Corn Snake Pantherophis guttatus The corn snake is a harmless North American rat snake — a slender orange constrictor that climbs, burrows, and keeps farm rodents down. Docile and easy to breed, it is the world's top pet snake. Read the guide →
Birds LC Corncrake Crex crex The corncrake lives in hay meadows rather than marshes, its rasping "crex-crex" call giving the species its scientific name, while mechanised mowing pushed it toward decline in Western Europe. Read the guide →
Birds LC Correndera Pipit Anthus correndera The correndera pipit ranges across open grassland from Peru all the way to Tierra del Fuego, nesting directly on the ground and relying on cryptic plumage to stay hidden. Read the guide →
Amphibians CR Corroboree Frog Pseudophryne corroboree A corroboree frog is a tiny yellow-and-black amphibian of Australia's alpine bogs, one of the few vertebrates that makes its own poison, and now nearly wiped out by an introduced fungus. Read the guide →
Mammals LC Corsac Fox Vulpes corsac The corsac fox roams the open steppe and semi-desert of Central Asia in loose social groups, growing a notably thick winter coat to survive harsh continental winters. Read the guide →
Fish LC Corydoras Corydoras A corydoras is a small armoured whiskered South American catfish that shoals along the bottom, gulps air from the surface through its gut, and is one of the most popular aquarium fish. Read the guide →
Birds LC Coscoroba Swan Coscoroba coscoroba The coscoroba swan is the smallest and most goose-like of the swans, the sole member of its own genus, distinguished from true swans by its shorter neck and bright red bill. Read the guide →
Birds LC Cotinga Cotingidae A cotinga is a member of one of the most visually and behaviourally extreme songbird families in the Americas, ranging from brilliant blue fruit-eaters to the loudest bird ever recorded. Read the guide →
Mammals CR Cotton-Top Tamarin Saguinus oedipus The cotton-top tamarin wears a wild crest of white hair and is one of the most endangered primates on Earth, found in only a small part of Colombia. Read the guide →
Reptiles LC Cottonmouth Agkistrodon piscivorus The cottonmouth, or water moccasin, is a thick-bodied semi-aquatic pit viper of the southeastern United States that gapes to flash the white lining of its mouth when it feels cornered. Read the guide →
Amphibians LC Couch's Spadefoot Toad Scaphiopus couchii Couch's spadefoot spends up to 10 months a year buried in the desert, waits underground for the vibration of monsoon rain, then breeds in puddles whose tadpoles go from egg to toadlet in eight days. Read the guide →
Mammals LC Cougar Puma concolor The cougar goes by more names than any other animal and roams from the Yukon to Patagonia. Learn why it isn't a "big cat", how far it can leap, and why it screams instead of roars. Read the guide →
Birds LC Courser Cursorius spp. The courser sprints across open desert and grassland on long legs rather than flying to escape danger, a fast ground bird built more like a small roadrunner than a typical wading-bird family member. Read the guide →
Amphibians NT Cow Knob Salamander Plethodon punctatus The Cow Knob salamander survives only along a single narrow ridgeline on the Virginia-West Virginia border, one of the smallest natural ranges of any salamander species in the Appalachians. Read the guide →
Birds LC Cowbird Molothrus A cowbird is a New World blackbird that never builds a nest, instead laying its eggs in other birds' nests, and the brown-headed cowbird parasitises more than 200 host species. Read the guide →
Fish VU Cownose Ray Rhinoptera bonasus The cownose ray gets its name from a fleshy, notched, cow-like snout used to dig clams and oysters out of the seabed. It migrates in schools of thousands and can leap clear of the water. Read the guide →
Invertebrates LC Cowrie Cypraeidae A cowrie's glossy, domed shell was once traded as actual currency across large parts of Africa, Asia, and the Pacific, its polished look kept up by a living mantle that recoats the shell over time. Read the guide →
Mammals LC Coyote Canis latrans The coyote has expanded across North America and into its cities faster than any other large predator, thriving under intense hunting pressure. Learn how it adapts, hunts, and outlasts persecution. Read the guide →
Mammals LC Coypu Myocastor coypus The coypu has bright orange front teeth stained by iron in the enamel, a semi-aquatic rodent whose fur-trade releases turned it into an invasive species worldwide. Read the guide →
Invertebrates NE Crab Brachyura A crab is a crustacean with a short, flattened, armoured body and a pair of pincers, a shape so useful that unrelated crustaceans have evolved into crab-like forms again and again. Read the guide →
Amphibians LC Crab-eating Frog Fejervarya cancrivora The crab-eating frog is one of the only amphibians on Earth able to tolerate brackish and even nearly full-strength seawater, surviving in mangrove swamps that would kill almost any other frog. Read the guide →
Mammals EN Crab-eating Macaque Macaca fascicularis The crab-eating macaque, or long-tailed macaque, swims and forages on Southeast Asian shores and riverbanks, uses stone tools to crack shellfish, and is now listed as Endangered. Read the guide →
Mammals LC Crab-Eating Mongoose Herpestes urva The crab-eating mongoose has partially webbed feet for swimming after its favourite prey, an Asian mongoose species that forages along streams and rice paddies rather than dry savanna. Read the guide →
Mammals LC Crabeater Seal Lobodon carcinophaga The crabeater seal is likely the most numerous large wild mammal on Earth after humans, despite its name feeding almost entirely on krill filtered through uniquely lobed, interlocking teeth. Read the guide →
Birds NE Crane Gruidae A crane is a tall wetland bird famous for leaping courtship dances, bugling calls that carry for kilometres, and migrations that take some species over the Himalayas at the height of a jet. Read the guide →
Invertebrates NE Crane Fly Tipulidae The crane fly is the giant, long-legged insect often called a mosquito hawk, though it does not hunt mosquitoes or bite anyone, and most adults do not feed at all before they die. Read the guide →
Fish LC Crappie Pomoxis spp. The crappie schools in enormous numbers around submerged brush and timber, a light-sensitive panfish that feeds most actively at dawn and dusk and ranks among North America's most popular sport fish. Read the guide →
Amphibians NT Crawfish Frog Lithobates areolatus The crawfish frog of the American Midwest lives year-round in an abandoned crayfish burrow, ambushing insects from the entrance, and it has one of the loudest calls of any North American frog. Read the guide →
Invertebrates NE Crayfish Astacoidea and Parastacoidea Crayfish are freshwater crustaceans that look like small lobsters, found on every continent but Africa and Antarctica, digging burrows and carrying their young in a cluster under the tail. Read the guide →
Fish LC Creek Chub Semotilus atromaculatus The creek chub builds a gravel nest mound by carrying stones one at a time in its mouth, a common minnow whose construction efforts sometimes attract other fish species to spawn on the same pile. Read the guide →
Fish LC Creek Chubsucker Erimyzon oblongus The creek chubsucker vacuums organic matter directly off the streambed with a downturned, sucker-shaped mouth, then sorts out the edible portion before spitting the rest back into the current. Read the guide →
Fish LC Creole Perch Percichthys trucha The creole perch is a native Patagonian freshwater fish increasingly outcompeted in its own rivers and lakes by introduced trout and salmon. Read the guide →
Reptiles LC Crested Anole Anolis cristatellus The crested anole has spread from Puerto Rico to several other regions through the pet trade and shipping, and males raise a distinct tail crest specifically during territorial disputes with rivals. Read the guide →
Mammals CR Crested Black Macaque Macaca nigra The crested black macaque is a Critically Endangered black monkey of northern Sulawesi with a tall crest of hair, best known worldwide for the 2011 monkey selfie, and heavily hunted for food. Read the guide →
Birds LC Crested Caracara Caracara plancus The crested caracara belongs to the falcon family but acts like a vulture, walking across open ground on long legs to scavenge carrion and steal meals rather than chasing prey through the air. Read the guide →
Birds LC Crested Duck Lophonetta specularioides The crested duck sports a shaggy tuft of feathers on the back of its head, ranging from lowland Patagonian coastlines to high-altitude Andean lakes across a remarkably wide range of elevations. Read the guide →
Birds NT Crested Eagle Morphnus guianensis The crested eagle is a large, slender relative of the harpy eagle, hunting snakes and mammals across the Amazon basin's intact lowland rainforest. Read the guide →
Reptiles VU Crested Gecko Correlophus ciliatus The crested gecko was thought extinct until it was rediscovered in 1994 on one island. It cannot regrow its tail, laps up fruit and nectar, and has become one of the world's most kept pet reptiles. Read the guide →
Mammals LC Crested Porcupine Hystrix cristata The crested porcupine rattles specialised hollow quills as a warning before ever using them, backing into a threat rather than the popular myth of throwing spines. Read the guide →
Amphibians NT Crevice Salamander Plethodon longicrus The crevice salamander retreats deep into rock crevices during dry periods, a narrow-range southern Appalachian endemic named for the very shelter that lets it survive what would otherwise dry it out. Read the guide →
Reptiles LC Crevice Spiny Lizard Sceloporus poinsettii The crevice spiny lizard spends most of its life wedged into rock crevices, retreating so quickly and completely when threatened that it can seem to simply vanish from an open rock face. Read the guide →
Invertebrates NE Cricket Gryllidae Crickets are long-whiskered, mostly nocturnal insects whose males sing by rubbing their wings together, and one is farmed for food while another tells the temperature by its chirp rate. Read the guide →
Amphibians LC Cricket Frog Acris A cricket frog is a tiny North American frog named for its dry clicking call, like two pebbles tapped together, and it can leap over a metre from a 3-centimetre body. Read the guide →
Birds LC Crissal Thrasher Toxostoma crissale The crissal thrasher gets its name from a rust-coloured patch beneath its tail, one of the only field marks on a dull grey bird that spends nearly its life hidden inside dense desert thickets. Read the guide →
Fish NE Croaking Gourami Trichopsis vittata The croaking gourami produces an audible croaking sound by vibrating muscles against its pectoral fins, one of the few aquarium fish whose courtship and territorial displays can actually be heard. Read the guide →
Reptiles NE Crocodile Crocodylidae A crocodile is the largest reptile alive, an ambush predator whose lineage is older than the last dinosaurs, with the strongest bite ever measured and jaws that sense a single ripple on the water. Read the guide →
Reptiles LC Crocodile Monitor Varanus salvadorii The crocodile monitor is a huge tree-climbing lizard of New Guinea, often called the longest lizard in the world because more than half its length is a whip-like tail used for balance. Read the guide →
Amphibians NT Crocodile Newt Tylototriton A crocodile newt is a warty, ridged Asian amphibian named for a bony head and back structure resembling a miniature crocodile, producing a distasteful skin toxin advertised by bold warning colours. Read the guide →
Birds LC Crossbill Loxia A crossbill is a finch with an unusual bill in which the upper and lower tips cross over each other, a specialised tool for prying seeds out of unopened conifer cones. Read the guide →
Birds NE Crow Corvidae A crow is a member of the corvid family, among the most intelligent of all birds, able to make and use tools, recognise individual human faces, and hold what looks like a funeral over a dead crow. Read the guide →
Invertebrates NE Crown-of-thorns Starfish Acanthaster planci The crown-of-thorns starfish is a large, venomous-spined sea star that eats living coral, and periodic population explosions of it are one of the main causes of coral loss on Indo-Pacific reefs. Read the guide →
Mammals EN Crowned Lemur Eulemur coronatus The crowned lemur gets its name from a distinctive orange "crown" marking on its head, with males and females showing noticeably different coat colours and patterns. Read the guide →
Fish LC Crucian Carp Carassius carassius The crucian carp is a deep, golden, barbel-less pond fish that survives for months without oxygen under winter ice and grows a deeper body when pike are around. Read the guide →
Amphibians LC Crucifix Frog Notaden bennettii The crucifix frog is a round Australian frog marked with a cross of coloured spots. Threatened, its skin oozes a fast-setting natural glue that gums up ants and is being tested as a surgical adhesive. Read the guide →
Invertebrates LC Crystal Jellyfish Aequorea victoria The crystal jellyfish produces a glowing protein that transformed modern biology and medicine, now used worldwide to make living cells visibly glow under a microscope. Read the guide →
Reptiles CR Cuban Crocodile Crocodylus rhombifer The Cuban crocodile is a small, agile, boldly speckled crocodile that survives only in two Cuban swamps. It leaps, walks on land with ease, and is one of the most endangered crocodiles on Earth. Read the guide →
Mammals LC Cuban Hutia Capromys pilorides The Cuban hutia is a stocky, tree-climbing rodent of Cuba and nearby islands, one of the largest surviving hutias and a rare native mammal of the Caribbean. Read the guide →
Reptiles VU Cuban Iguana Cyclura nubila The Cuban iguana is the largest native land vertebrate remaining in the Caribbean, a spiny-backed herbivore declining on the mainland but thriving on a handful of protected offshore cays. Read the guide →
Amphibians LC Cuban Tree Frog Osteopilus septentrionalis The Cuban tree frog is the largest tree frog in North America and a destructive invader in Florida, where it eats native frogs and lizards and clogs plumbing and electrical boxes. Read the guide →
Birds NE Cuckoo Cuculidae A cuckoo is a slender, long-tailed bird, famous for the species that lay eggs in other birds' nests, tricking the hosts into raising a chick that hatches early and heaves out their own young. Read the guide →
Fish LC Cuckoo Ray Leucoraja naevus The cuckoo ray is a small, buff-brown ray of the north-eastern Atlantic shelf marked with a striking, peacock-like eye spot on each wing, which gives it a butterfly look. Read the guide →
Invertebrates NE Cuckoo Wasp Chrysididae The cuckoo wasp sneaks its eggs into the nests of other wasps and bees, then curls into a tight, armoured ball to survive a furious host's retaliation. Read the guide →
Fish LC Cuckoo Wrasse Labrus mixtus The cuckoo wrasse is a vividly coloured wrasse of north-eastern Atlantic reefs in which the orange females with dark spots change sex into blue-headed, orange-bodied males. Read the guide →
Birds LC Cuckoo-Roller Leptosomus discolor The cuckoo-roller is the only member of its family, a Madagascar endemic that carries the roller name despite never performing the acrobatic tumbling flight that gives true rollers theirs. Read the guide →
Mammals LC Culpeo Fox Lycalopex culpaeo The culpeo fox is the second-largest wild canid in South America, ranging from lowland Patagonian steppe to high Andean peaks and preying heavily on guanaco young alongside a varied omnivorous diet. Read the guide →
Amphibians LC Cumberland Plateau Salamander Plethodon kentucki The Cumberland Plateau salamander was only recognized as its own species after researchers found it living alongside a nearly identical relative without the two ever interbreeding. Read the guide →
Birds VU Curassow Crax A curassow is a large, turkey-sized forest bird crowned with a curled crest of feathers, its deep booming calls carrying through the canopy thanks to an unusually elongated windpipe. Read the guide →
Birds LC Curl-crested Aracari Pteroglossus beauharnaesii The curl-crested aracari wears feathers on its head so tightly curled and glossy that they look almost artificial, an appearance unlike anything else found anywhere in the bird world. Read the guide →
Birds NT Curlew Numenius A curlew is a large wading bird with a long, downward-curved bill built for probing deep into mud for worms, and its haunting, bubbling call is one of the most recognisable sounds of open wetlands. Read the guide →
Reptiles LC Curly-Tailed Lizard Leiocephalus The curly-tailed lizard curls its tail up over its back like a small scorpion when alarmed, a distinctive signal that seems to tell a predator it has already been spotted. Read the guide →
Birds LC Currawong Strepera spp. The currawong solves problems and mimics sounds with a flexibility that puts it among Australia's most vocally accomplished birds, an opportunistic omnivore whose calls a lyrebird will happily copy. Read the guide →
Birds LC Curve-Billed Thrasher Toxostoma curvirostre The curve-billed thrasher builds its nest inside the spiniest cholla cactus it can find, trading the risk of getting impaled itself for a nursery almost nothing else is willing to reach into. Read the guide →
Invertebrates LC Cushion Star Culcita spp. The cushion star barely looks like a starfish at all, its arms so short and its body so thick and puffy that it resembles a plump pillow slowly crawling across the reef. Read the guide →
Fish LC Cusk Eel Ophidiidae The cusk eel family once held the record for the deepest fish ever recovered, a group of elongated, eel-like fish ranging from shallow reefs to the crushing pressure of ocean trenches. Read the guide →
Fish LC Cutlip Minnow Exoglossum maxillingua The cutlip minnow has a strange, three-lobed jaw used not for grazing algae but for nipping fins and scales off other fish, a specialised feeding habit unusual among small North American minnows. Read the guide →
Fish LC Cutthroat Eel Synaphobranchidae The cutthroat eel has fused gill openings forming a single slit across its throat, giving the family its unsettling name, with species found from continental slopes to abyssal trenches. Read the guide →
Fish LC Cutthroat Trout Oncorhynchus clarkii The cutthroat trout takes its name from a bold slash of red or orange under its jaw, a feature distinctive enough to separate the species from other North American trout at a glance. Read the guide →
Invertebrates LC Cuttlefish Sepia officinalis The common cuttlefish is a colour-blind master of camouflage that changes its skin pattern in a heartbeat, hypnotises prey with moving stripes, and floats using a chambered internal shell. Read the guide →
Mammals LC Cuvier's Beaked Whale Ziphius cavirostris Cuvier's beaked whale holds the record for the deepest and longest dive ever recorded in a marine mammal, descending nearly three kilometres and staying under for well over three hours hunting squid. Read the guide →
Reptiles LC Cuvier's Dwarf Caiman Paleosuchus palpebrosus Cuvier's dwarf caiman is the smallest crocodilian, a heavily armoured, shy caiman of South American forest streams that grows to little more than a metre and a half. Read the guide →
Fish LC Cypress Darter Etheostoma proeliare The cypress darter is one of the smallest darters in North America, thriving in the slow, tannin-stained backwaters of cypress swamps that most of its fast-water-loving relatives avoid entirely. Read the guide →
Mammals LC Dall Sheep Ovis dalli The Dall sheep is the only entirely white wild sheep species in the world, a northern mountain specialist whose pale coat provides camouflage against snow across remote alpine North America. Read the guide →
Mammals LC Damaraland Mole-Rat Fukomys damarensis The Damaraland mole-rat is one of only two known eusocial mammals, living in colonies with a single breeding queen who suppresses reproduction in every other member. Read the guide →
Fish NE Damselfish Pomacentridae A damselfish is a small, bold reef fish that chases animals many times its size off its patch, and the family includes the clownfish, which lives unharmed among a sea anemone's stinging tentacles. Read the guide →
Invertebrates NE Damselfly Zygoptera The damselfly is the slender, weak-flying cousin of the dragonfly, resting with its wings folded along its body, and its larvae breathe through three leaf-like gills at the tail. Read the guide →
Birds LC Dark-bellied Cinclodes Cinclodes patagonicus The dark-bellied cinclodes forages by walking along the water's edge rather than flying, a ground-based hunting style shared with other cinclodes species of Patagonian streams and shorelines. Read the guide →
Birds LC Dark-Eyed Junco Junco hyemalis The dark-eyed junco is nicknamed the snowbird for arriving at feeders each winter, and its plumage varies so much by region that several forms were once classed as separate species. Read the guide →
Birds LC Dark-faced Ground-Tyrant Muscisaxicola maclovianus The dark-faced ground-tyrant hunts insects from open ground across Patagonia and the Falkland Islands, identified by its sharply contrasting dark facial mask. Read the guide →
Invertebrates LC Darkling Beetle Tenebrionidae The darkling beetle includes desert species that harvest their own drinking water by tilting into the wind and letting fog condense down grooves straight into their mouths. Read the guide →
Fish LC Dartfish Ptereleotridae The dartfish hovers just above its burrow entrance, ready to vanish in an instant with the quick, darting burst of speed that gives the family its name. Read the guide →
Invertebrates NE Darwin's Bark Spider Caerostris darwini Darwin's bark spider builds the largest web of any spider — an orb up to 2.8 square metres slung across a river on anchor lines 25 metres long, from the toughest biological material known. Read the guide →
Mammals EN Darwin's Fox Lycalopex fulvipes Darwin's fox survives in just two isolated populations, one on Chiloe Island and a tiny mainland population once thought extinct, making it one of the rarest canids on Earth. Read the guide →
Amphibians EN Darwin's Frog Rhinoderma darwinii Darwin's frog is a small, leaf-mimicking frog of Chile and Argentina, famous because the male broods the tadpoles in his vocal sac until they hop out of his mouth as froglets. Read the guide →
Amphibians EN Darwin's Frog Rhinoderma darwinii Darwin's frog is a leaf-mimicking Chilean frog in which the father swallows his own developing eggs and carries the tadpoles in his vocal sac until they hop out as froglets. Read the guide →
Birds NT Darwin's Rhea Rhea pennata Darwin's rhea is the smaller of the two rhea species, adapted to the cold, windswept grassland of Patagonia and the high Andean puna rather than the warmer plains of its larger relative. Read the guide →
Mammals LC Daubenton's Bat Myotis daubentonii Daubenton's bat is the water bat, skimming just above lakes and rivers to scoop insects off the surface with its large feet and tail membrane. Read the guide →
Mammals LC De Brazza's Monkey Cercopithecus neglectus The De Brazza's monkey can freeze motionless for hours to avoid detection, making this widespread swamp forest primate one of the hardest to actually spot. Read the guide →
Invertebrates NE Dead Leaf Mantis Deroplatys desiccata The dead leaf mantis is a rainforest ambush predator whose flattened, brown, veined body and crinkled shield mimic a dead leaf so precisely it can hang in the litter, swaying, completely unseen. Read the guide →
Invertebrates NE Death's Head Hawkmoth Acherontia atropos The death's head hawkmoth carries a skull-shaped marking on its thorax and can squeeze into beehives to steal honey, protected by a scent that mimics the colony's own. Read the guide →
Invertebrates NE Deathstalker Scorpion Leiurus quinquestriatus The deathstalker has the most dangerous venom of any scorpion — a mix of neurotoxins that can kill a child. That same venom contains a peptide now used to make brain tumours glow during surgery. Read the guide →
Invertebrates NE Decorator Crab Camposcia retusa The decorator crab covers its own shell and legs with living sponges, anemones, and seaweed, holding them on with hooked bristles. Some are so encrusted they no longer look like a crab at all. Read the guide →
Invertebrates LC Deepstaria Deepstaria enigmatica The deepstaria has an enormous, sheet-like bell rather than the familiar dome shape of most jellyfish, folding open to engulf prey rather than stinging it with trailing tentacles. Read the guide →
Fish LC Deepwater Sculpin Myoxocephalus thompsonii The deepwater sculpin survives as a glacial relict, isolated in the cold depths of a handful of large northern lakes since the last ice age, unable to tolerate the warmer water separating populations. Read the guide →
Mammals NE Deer Cervidae A deer is a hoofed browser whose males grow and shed a fresh set of branching antlers every year, the fastest normal bone growth known in any animal, then drop them and start again. Read the guide →
Mammals LC Deer Mouse Peromyscus maniculatus The deer mouse is one of the most widespread mammals in North America, found from Alaskan tundra to Mexican desert, and its role as a hantavirus reservoir keeps public health officials watching. Read the guide →
Invertebrates NE Deer Tick Ixodes scapularis The deer tick is the primary carrier of Lyme disease in eastern North America, and it is the barely visible, poppy-seed-sized nymph stage, not the larger adult, that causes most human infections. Read the guide →
Mammals LC Degu Octodon degus The degu communicates through an unusually large vocabulary of calls and can see into the ultraviolet spectrum, markings on its own fur invisible to human eyes. Read the guide →
Reptiles LC DeKay's Brown Snake Storeria dekayi DeKay's brown snake is a tiny, completely harmless North American snake often confused by name with Australia's deadly eastern brown snake, despite the two having nothing but a name in common. Read the guide →
Amphibians NT Del Norte Salamander Plethodon elongatus The Del Norte salamander wedges its unusually long, slender body deep into rocky talus and old-growth forest debris, a lungless specialist confined to a narrow strip of the Pacific Northwest. Read the guide →
Fish LC Demasoni Cichlid Pseudotropheus demasoni The demasoni cichlid is barely six centimetres long yet considered one of the most aggressive fish, inch for inch, in the entire mbuna group, requiring large groups just to spread out the hostility. Read the guide →
Birds LC Des Murs's Wiretail Sylviorthorhynchus desmursii Des Murs's wiretail is a tiny songbird of southern beech forest carrying an extraordinarily long, wire-thin tail several times the length of its own body, the sole member of its own genus. Read the guide →
Reptiles LC Desert Death Adder Acanthophis pyrrhus The desert death adder buries itself in red sand until only its eyes and a worm-like tail tip show, luring prey close before striking with one of the fastest recorded attacks of any snake. Read the guide →
Reptiles LC Desert Grassland Whiptail Aspidoscelis uniparens Every desert grassland whiptail is female, descended from a single ancient hybridization between two other whiptail lizards, reproducing by cloning itself without any males at all. Read the guide →
Mammals LC Desert Hedgehog Paraechinus aethiopicus The desert hedgehog shrugs off scorpion venom that would trouble many other predators, feeding confidently on the very scorpions other animals learn to avoid. Read the guide →
Reptiles LC Desert Horned Lizard Phrynosoma platyrhinos The desert horned lizard buries itself in loose sand until only its eyes show, a flattened, spiny ambush specialist that relies on ants and camouflage rather than speed to survive the open desert. Read the guide →
Reptiles LC Desert Iguana Dipsosaurus dorsalis The desert iguana is one of the most heat-tolerant lizards on Earth, out foraging on flowers and leaves at body temperatures near 45°C, when almost every other desert animal has retreated to shade. Read the guide →
Reptiles LC Desert Kingsnake Lampropeltis splendida The desert kingsnake thrives in some of the harshest, driest terrain in the Southwest, immune to the venom of the rattlesnakes it hunts and equally at home raiding rodent burrows or bird nests. Read the guide →
Reptiles LC Desert Night Lizard Xantusia vigilis The desert night lizard spends nearly its entire life hidden beneath a single fallen yucca or Joshua tree limb, rarely traveling more than a few meters away from that same log its whole life. Read the guide →
Mammals LC Desert Pocket Mouse Chaetodipus penicillatus The desert pocket mouse is a tiny, long-tailed seed collector of the American Southwest that carries food in fur-lined cheek pouches and can live without drinking. Read the guide →
Amphibians NT Desert Rain Frog Breviceps macrops The desert rain frog is a round, grumpy-looking burrowing frog from a narrow strip of southwest African coast. It has no tadpole stage, and its threat call is a high squeak that went viral online. Read the guide →
Amphibians CR Desert Slender Salamander Batrachoseps aridus The desert slender salamander survives in a single spring-fed canyon, making it one of the most range-restricted amphibians on Earth despite living in a landscape almost devoid of moisture. Read the guide →
Reptiles LC Desert Spiny Lizard Sceloporus magister The desert spiny lizard is covered in rough, keeled, pointed scales, and males flash vivid blue throat and belly patches during head-bobbing displays atop rocks and desert vegetation. Read the guide →
Reptiles CR Desert Tortoise Gopherus agassizii The desert tortoise survives the Mojave by digging deep burrows and storing almost a year's water in its bladder, drinking its fill only when a rare desert storm fills the natural basins. Read the guide →
Invertebrates NE Devil's Coach-horse Ocypus olens The devil's coach-horse is a long black rove beetle that rears its tail like a scorpion and opens its jaws when threatened, a night hunter of slugs and worms in gardens and woods. Read the guide →
Invertebrates NE Devil's Flower Mantis Idolomantis diabolica The devil's flower mantis is one of the largest mantises, an East African flower mimic that ambushes pollinators and, when threatened, rears up to flash a startling burst of red, white and blue. Read the guide →
Fish CR Devils Hole Pupfish Cyprinodon diabolis The Devils Hole pupfish lives in one sunlit desert pool in Nevada, the smallest natural range of any vertebrate, and its survival once hinged on a US Supreme Court ruling about groundwater. Read the guide →
Mammals EN Dhole Cuon alpinus The dhole is a russet wild dog of Asia that hunts in large, coordinated packs and communicates with eerie whistles. Packs bring down prey many times their size and stand their ground against tigers. Read the guide →
Invertebrates NE Diabolical Ironclad Beetle Nosoderma diabolicum The diabolical ironclad beetle has an exoskeleton so tough that a car can drive over it without killing it, thanks to a jigsaw seam that locks its wing cases together. Read the guide →
Mammals CR Diademed Sifaka Propithecus diadema The diademed sifaka is one of the largest living lemurs, leaping between rainforest trees in powerful sideways bounds and crossing open ground with a comical upright hop. Read the guide →
Fish LC Diamond Killifish Fundulus xenicus The diamond killifish carries a body shaped almost like the gem that gives it its name, a small, deep-bodied fish restricted to salt marsh pools along a narrow stretch of the Gulf Coast. Read the guide →
Reptiles LC Diamondback Terrapin Malaclemys terrapin The diamondback terrapin is the only turtle living exclusively in brackish water, patrolling salt marshes where fresh and salt water mix. Glands near its eyes let it excrete salt like a sea turtle. Read the guide →
Reptiles LC Diamondback Water Snake Nerodia rhombifer The diamondback water snake carries a bold diamond-patterned back that leads many to mistake it for a venomous species, a large, harmless fish-eater often killed needlessly out of unwarranted fear. Read the guide →
Mammals VU Diana Monkey Cercopithecus diana The Diana monkey is named for a crescent-shaped white brow band said to resemble the bow carried by the Roman goddess of the hunt. Read the guide →
Mammals VU Dibatag Ammodorcas clarkei The dibatag curls its tail up over its back like a dog when it runs, a slender, long-necked antelope of the Horn of Africa that browses standing on its hind legs. Read the guide →
Reptiles LC Dice Snake Natrix tessellata The dice snake is a non-venomous semi-aquatic snake of rivers and lakes in Europe and Asia, with a chequered pattern like dice, that hunts fish underwater and plays dead when threatened. Read the guide →
Invertebrates LC Digger Bee Anthophora The digger bee excavates its own burrow into bare soil, and a dense aggregation of females digging side by side can leave a patch of ground looking like a buzzing construction site. Read the guide →
Mammals LC Dik-dik Madoqua kirkii The dik-dik is a hare-sized African antelope with huge eyes and a long, mobile snout. Pairs mate for life, mark their territory with tears and dung, and get nearly all their water from plants. Read the guide →
Mammals VU Dingo Canis dingo The dingo is Australia's largest land predator — an ancient free-living dog that arrived with seafarers about 3,500 years ago, can turn its head almost 180°, and is now hybridising with feral dogs. Read the guide →
Mammals LC Disc-Winged Bat Thyroptera tricolor The disc-winged bat clings inside rolled leaves using suction-cup discs on its wrists and ankles, moving to a fresh leaf every day or two as each one unfurls. Read the guide →
Fish LC Discus Symphysodon A discus is a round, disc-shaped Amazon cichlid, prized as the king of the aquarium, and unusual in that both parents feed their newly hatched young on mucus from their own skin. Read the guide →
Mammals LC Disk-winged Bat Thyroptera tricolor The disk-winged bat carries suction-cup-like pads on its wrists and ankles, letting it cling to the smooth inner surface of a single rolled-up leaf each night. Read the guide →
Invertebrates LC Diving Beetle Dytiscidae A diving beetle is a streamlined, air-carrying pond predator whose larva, the water tiger, injects prey with digestive juices and sucks it dry, and both stages take tadpoles and small fish. Read the guide →
Invertebrates LC Diving Bell Spider Argyroneta aquatica The diving bell spider is the only spider that lives its whole life underwater. It spins a dome of silk among pondweed, fills it with air carried down on its body, and lives inside this diving bell. Read the guide →
Amphibians EN Dixie Valley Toad Anaxyrus williamsi The Dixie Valley toad survives entirely within a single square mile of geothermal wetland in the Nevada desert, one of the smallest ranges of any amphibian species on Earth. Read the guide →
Mammals LC Djungarian Hamster Phodopus sungorus The Djungarian hamster is a tiny steppe hamster of Central Asia that uses the shortening days of autumn as a signal to grow a thick, paler winter coat and cut back its body weight. Read the guide →
Invertebrates NE Dobsonfly Corydalinae The male dobsonfly has jaws half the length of its body that are too unwieldy to bite with and are used only to grapple rival males. Its aquatic larva, the hellgrammite, is prized fishing bait. Read the guide →
Birds EX Dodo Raphus cucullatus The dodo was a large flightless pigeon that lived only on Mauritius and feared nothing. Within a century of European contact it was gone, killed off mostly by the animals that arrived with the ships. Read the guide →
Invertebrates NE Dog Whelk Nucella lapillus The dog whelk is a predatory sea snail of rocky northeast Atlantic shores that drills into barnacles and mussels, takes its shell colour from its diet, and was hit by antifouling paint. Read the guide →
Fish LC Dollar Sunfish Lepomis marginatus The dollar sunfish is named for its small, round, coin-like shape, one of the smallest sunfish species and easy to overlook in the quiet, vegetated waters it prefers. Read the guide →
Mammals NE Dolphin Delphinidae A dolphin is a small toothed whale, one of the most intelligent animals alive, that hunts by echolocation, lives in fluid social groups, and passes hunting traditions from mother to calf. Read the guide →
Birds LC Dolphin Gull Leucophaeus scoresbii The dolphin gull scavenges along the rocky shores of southern South America, its striking red bill and legs standing out against jet-black and white plumage. Read the guide →
Invertebrates NE Dor Beetle Geotrupes stercorarius The dor beetle is a heavy, glossy black dung beetle with a metallic blue-violet underside that buzzes through dusk grassland, digs deep burrows beneath dung, and is often covered in clinging mites. Read the guide →
Mammals VU Dorcas Gazelle Gazella dorcas The dorcas gazelle can survive almost entirely without drinking water, a small, pale desert gazelle ranging across the Sahara and parts of the Middle East. Read the guide →
Birds LC Dot-Winged Antwren Microrhopias quixensis The dot-winged antwren carries neat rows of white spots across its wing feathers, a pattern that gives the species its name and helps with identification. Read the guide →
Mammals CR Douc Langur Pygathrix nemaeus The douc langur carries a patchwork of vivid colours across its face, limbs, and body, widely considered one of the most strikingly colourful primates alive. Read the guide →
Birds LC Downy Woodpecker Dryobates pubescens The downy woodpecker is the smallest woodpecker in North America, nearly identical in pattern to the much larger hairy woodpecker, and a familiar visitor to backyard suet feeders. Read the guide →
Invertebrates NE Dragonfly Anisoptera The dragonfly is a hunting insect with four independent wings and one of the highest kill rates of any predator, whose young spend months or years underwater before weeks in the air. Read the guide →
Invertebrates LC Dragonhunter Hagenius brevistylus The dragonhunter is one of the largest dragonflies in North America, bold enough to attack and eat other dragonflies nearly its own size, including species most predators avoid entirely. Read the guide →
Mammals EN Drill Mandrillus leucophaeus The drill is a close relative of the mandrill but far less known and far more endangered, restricted to a tiny sliver of West African rainforest. Read the guide →
Mammals NE Dromedary Camel Camelus dromedarius The dromedary is the one-humped camel of Arabia and North Africa — a desert specialist that stores fat in its hump, lets its body temperature swing, and can drink 100 litres in minutes. Read the guide →
Invertebrates NE Drone Fly Eristalis tenax The drone fly is a honeybee-mimicking hoverfly with a stout, orange-and-brown body whose larva is a rat-tailed maggot that breathes through a long tube in stagnant water. Read the guide →
Birds LC Drongo Dicruridae A drongo is a fiercely territorial bird that has learned to imitate the alarm calls of other species, sometimes falsely, purely to scare them away from food it can then steal for itself. Read the guide →
Birds NE Duck Anatidae A duck is a small waterfowl with a broad flat bill, waterproof feathers kept oiled by preening, and often a bright male and a drab female, the female usually raising the ducklings alone. Read the guide →
Mammals VU Dugong Dugong dugon The dugong is a fully marine relative of the manatee that grazes seagrass in the warm shallows of the Indo-Pacific, has a dolphin-like fluked tail, and is the animal behind many mermaid stories. Read the guide →
Invertebrates NE Dumbo Octopus Grimpoteuthis spp. The dumbo octopus flaps two ear-like fins above its head to hover through the deep sea, the pose that gave it its name. It lives deeper than almost any other octopus known. Read the guide →
Invertebrates LC Dung Beetle Scarabaeus satyrus The dung beetle rolls a ball of animal droppings in a dead-straight line — navigating by the sun, the moon, polarised light, and, uniquely among animals, the glow of the Milky Way. Read the guide →
Invertebrates LC Dungeness Crab Metacarcinus magister The Dungeness crab anchors one of the Pacific Northwest's most valuable fisheries, a broad-shelled bottom-dweller whose sweet, tender meat has made it the region's signature seafood export. Read the guide →
Birds LC Dunlin Calidris alpina The dunlin gathers in enormous, tightly coordinated flocks that swirl over mudflats as a single shifting shape, and breeding birds carry a bold black belly patch found on few other small shorebirds. Read the guide →
Amphibians LC Dunn's Salamander Plethodon dunni Dunn's salamander stays closer to water than most of its lungless relatives, sheltering under rocks and logs right at the edge of Pacific coast streams and seepages. Read the guide →
Mammals LC Dusky Antechinus Antechinus swainsonii Male dusky antechinus mate frantically for barely two weeks each year, then die en masse from the exhaustion, leaving pregnant females to survive alone. Read the guide →
Fish LC Dusky Darter Percina sciera The dusky darter grows larger than many darter relatives, favoring deeper pools where it perches motionless on the bottom, propped up on its own pectoral fins between short bursts of movement. Read the guide →
Mammals LC Dusky Dolphin Lagenorhynchus obscurus The dusky dolphin performs some of the most varied acrobatic displays of any dolphin, including somersaults and spinning leaps, often coordinating cooperative hunts that drive fish into tight balls. Read the guide →
Amphibians CR Dusky Gopher Frog Lithobates sevosus The dusky gopher frog is one of the world's most endangered amphibians, a warty Mississippi frog that lives in gopher tortoise burrows and hides its eyes behind its hands when frightened. Read the guide →
Amphibians LC Dusky Salamander Desmognathus A dusky salamander is a small streamside salamander of Appalachian forests, one of the most abundant vertebrates in its habitat, that opens its mouth by lifting its skull instead of dropping its jaw. Read the guide →
Mammals DD Dusky-Footed Elephant Shrew Elephantulus fuscipes The dusky-footed elephant shrew is one of the least studied members of its order, known from so few records across remote Central Africa that basic facts about its life remain unclear. Read the guide →
Birds LC Dusky-headed Parakeet Aratinga weddellii The dusky-headed parakeet shows a muted grey-brown head contrasting with a bright green body, forming noisy flocks across the western Amazon basin. Read the guide →
Invertebrates NE Dust Mite Dermatophagoides A dust mite is a microscopic relative of ticks and spiders that lives in bedding and carpets eating flakes of shed human skin, and its droppings are a leading trigger of allergy and asthma. Read the guide →
Amphibians LC Dwarf Clawed Frog Hymenochirus A dwarf clawed frog is a thumbnail-sized, fully aquatic African frog with all four feet webbed and no tongue or teeth, that rests in a motionless spread-eagled float and is a common aquarium pet. Read the guide →
Reptiles VU Dwarf Crocodile Osteolaemus tetraspis The dwarf crocodile is the smallest crocodilian, rarely over 1.5 m, and one of the most armoured, with bony plates even on its eyelids. Some populations live and breed inside flooded caves. Read the guide →
Fish VU Dwarf Lanternshark Etmopterus perryi The dwarf lanternshark is the smallest known shark species, small enough to fit in the palm of a human hand, with light-producing organs along its belly used for counter-illumination camouflage. Read the guide →
Mammals LC Dwarf Mongoose Helogale parvula The dwarf mongoose is the smallest carnivore in Africa, living in tight social groups that form an unusual working partnership with hornbills to watch for shared predators. Read the guide →
Amphibians LC Dwarf Salamander Eurycea quadridigitata The dwarf salamander has only four toes on its hind feet rather than the usual five found on most salamanders, a subtle but reliable feature for identifying this tiny southeastern species. Read the guide →
Fish VU Dwarf Seahorse Hippocampus zosterae The dwarf seahorse is one of the smallest seahorse species in the world, clinging to seagrass with a prehensile tail and ambushing prey too small for most other fish to bother with. Read the guide →
Amphibians LC Dwarf Waterdog Necturus punctatus The dwarf waterdog is the smallest of the North American waterdogs, keeping its feathery external gills for life while rarely growing large enough to draw much attention. Read the guide →
Amphibians LC Dyeing Poison Frog Dendrobates tinctorius The dyeing poison frog is one of the largest poison dart frogs, boldly patterned in black, yellow and blue. Each population has its own colours, and males carry tadpoles up trees to canopy pools. Read the guide →
Birds NE Eagle Accipitridae An eagle is a large bird of prey with eyesight several times sharper than a human's, a grip that can exceed its own body weight, and a build made for killing animals as big as itself. Read the guide →
Fish NT Eagle Ray Myliobatidae An eagle ray glides through open water with wing-like fins beating in slow strokes, an active swimmer that will sometimes leap entirely clear of the surface for reasons still unexplained. Read the guide →
Reptiles LC Earless Lizard Holbrookia The earless lizard has no visible ear opening at all, its skin smooth and unbroken across the side of its head, a discreet adaptation for a fast desert sprinter that dives often into loose sand. Read the guide →
Reptiles DD Earless Monitor Lanthanotus borneensis The earless monitor is a secretive Bornean lizard so rarely seen it was once considered almost mythical among reptile researchers, and it is the sole living member of its own ancient lizard family. Read the guide →
Invertebrates LC Early Bumblebee Bombus pratorum The early bumblebee is a small, black bumblebee with a yellow collar, a yellow band, and an orange-red tail that emerges in early spring and runs a fast, short colony cycle that is over by midsummer. Read the guide →
Invertebrates NE Earthworm Lumbricus terrestris The earthworm is a burrowing segmented worm that eats its way through soil and dead leaves, mixing and aerating the ground, a process Charles Darwin showed slowly builds the world's topsoil. Read the guide →
Invertebrates NE Earwig Dermaptera An earwig is a slim nocturnal insect with a pair of curved pincers at its rear, folded wings it rarely uses, and, unusually for an insect, a mother that guards and grooms her eggs and young. Read the guide →
Amphibians LC Eastern Banjo Frog Limnodynastes dumerilii The eastern banjo frog is a burrowing Australian ground frog whose short, resonant bonk call sounds like a plucked banjo string, and a pond full of calling males sounds like a band tuning up. Read the guide →
Reptiles VU Eastern Box Turtle Terrapene carolina The eastern box turtle is a small land turtle of the eastern US that can fold its hinged shell shut into a sealed box, lives for many decades, and stays in a home range of a few hectares for life. Read the guide →
Reptiles LC Eastern Brown Snake Pseudonaja textilis The eastern brown snake has the second most toxic venom of any land snake and causes about 60% of Australia's snakebite deaths — because it is fast, nervous, and lives right where people do. Read the guide →
Invertebrates LC Eastern Carpenter Bee Xylocopa virginica The eastern carpenter bee excavates its own nest tunnel into solid wood, chewing through untreated timber with powerful jaws rather than relying on an existing cavity the way most other bees do. Read the guide →
Mammals LC Eastern Chipmunk Tamias striatus The eastern chipmunk is a small striped ground squirrel of North American woods and gardens that packs its cheek pouches with seeds, hoards them in a hidden burrow, and dozes through winter. Read the guide →
Invertebrates LC Eastern Comma Polygonia comma The eastern comma carries a tiny silver mark on its hindwing shaped like a comma rather than a question mark, the single detail that separates it from its extremely similar close relative. Read the guide →
Reptiles LC Eastern Copperhead Agkistrodon contortrix The eastern copperhead, a camouflaged pit viper of the US East and Midwest, causes more venomous bites than any other American snake and among the fewest deaths, because its venom is mild. Read the guide →
Reptiles LC Eastern Coral Snake Micrurus fulvius The eastern coral snake has the second-strongest venom of any North American snake but rarely bites — it is secretive, small-mouthed, and spends most of its life underground. Read the guide →
Mammals LC Eastern Cottontail Sylvilagus floridanus The eastern cottontail relies almost entirely on freezing motionless and camouflage to survive, bolting in a sudden zigzag sprint only as a genuine last resort against a predator too close to ignore. Read the guide →
Reptiles LC Eastern Diamondback Rattlesnake Crotalus adamanteus The eastern diamondback is the largest venomous snake in North America and the heaviest rattlesnake on Earth. It warns before it strikes, shelters in tortoise burrows, and is declining fast. Read the guide →
Reptiles LC Eastern Fence Lizard Sceloporus undulatus The eastern fence lizard's males flash blue belly patches during territorial push-up displays, a common species whose blue-throated dance has become a classic subject in lizard behaviour research. Read the guide →
Reptiles EN Eastern Fox Snake Pantherophis gloydi The eastern fox snake is a harmless constrictor so often mistaken for a rattlesnake, thanks to its coppery head and rattlesnake-mimicking tail vibration, that it is regularly killed by mistake. Read the guide →
Reptiles LC Eastern Glass Lizard Ophisaurus ventralis The eastern glass lizard looks exactly like a snake but has eyelids and ear openings a true snake never has, and when grabbed it can shatter its own tail into several wriggling pieces at once. Read the guide →
Mammals LC Eastern Gray Squirrel Sciurus carolinensis The eastern gray squirrel plants trees by burying nuts it never digs up, remembers cache sites, fakes burials when it thinks it is watched, and has turned much of Britain's woodland grey. Read the guide →
Mammals LC Eastern Grey Kangaroo Macropus giganteus The eastern grey kangaroo grazes in large mobs at dawn and dusk, with males settling rank through boxing matches using their powerful hind legs and forearms. Read the guide →
Reptiles LC Eastern Hognose Snake Heterodon platirhinos Threatened, the eastern hognose snake flares a cobra-like hood and hisses; if that fails it thrashes, vomits, rolls belly-up and plays dead, tongue lolling. It is harmless and very rarely bites. Read the guide →
Reptiles NT Eastern Indigo Snake Drymarchon couperi The eastern indigo snake is the longest native snake in North America, a glossy blue-black constrictor that regularly eats venomous rattlesnakes unharmed by their bites. Read the guide →
Birds LC Eastern Kingbird Tyrannus tyrannus The eastern kingbird fearlessly attacks hawks and crows many times its own size near its nest, and hides a fiery orange-red crown patch it flashes only during these confrontations. Read the guide →
Reptiles LC Eastern Kingsnake Lampropeltis getula The eastern kingsnake is a powerful constrictor that hunts and eats other snakes, rattlesnakes and copperheads included, and shrugs off a dose of their venom that would kill most animals. Read the guide →
Reptiles LC Eastern Long-necked Turtle Chelodina longicollis The eastern long-necked turtle is an Australian freshwater turtle with a neck as long as its shell that sucks in prey in a flash, smells foul when handled, and walks overland between wetlands. Read the guide →
Invertebrates LC Eastern Lubber Grasshopper Romalea microptera The eastern lubber grasshopper is too heavy and short-winged to fly or hop far, so it survives in plain sight through bold warning colours, a foul froth, and a foam-laced hiss instead of speed. Read the guide →
Birds NT Eastern Meadowlark Sturnella magna The eastern meadowlark is not actually a lark but a blackbird relative, and it stays reproductively separate from its near-identical western sibling species through song alone. Read the guide →
Mammals LC Eastern Mole Scalopus aquaticus The eastern mole spends nearly its entire life underground, digging tunnels fast enough to raise a visible ridge of soil in real time, a burrower most people notice only by the damage left behind. Read the guide →
Reptiles LC Eastern Mud Turtle Kinosternon subrubrum The eastern mud turtle spends much of the year buried in mud or leaf litter rather than open water, a small, secretive species equally comfortable walking overland as swimming its shallow wetlands. Read the guide →
Amphibians LC Eastern Narrow-mouthed Toad Gastrophryne carolinensis The eastern narrow-mouthed toad is a small, pointy-headed amphibian that eats mainly ants and termites, sometimes found sharing a burrow with a tarantula that appears to tolerate it on purpose. Read the guide →
Amphibians LC Eastern Narrowmouth Toad Gastrophryne carolinensis The eastern narrowmouth toad specialises almost entirely on ants and termites, using a small, pointed head to push into tight nest galleries that would keep most other amphibians out entirely. Read the guide →
Amphibians LC Eastern Newt Notophthalmus viridescens The eastern newt of North America has a three-stage life — aquatic larva, land-dwelling orange "red eft," then aquatic adult — and its skin carries a nerve toxin that keeps predators away. Read the guide →
Birds LC Eastern Phoebe Sayornis phoebe The eastern phoebe announces itself with a raspy call resembling its own name, dips its tail constantly while perched, and often builds a mud nest directly on human structures. Read the guide →
Invertebrates LC Eastern Pondhawk Erythemis simplicicollis The eastern pondhawk is an aggressive, ground-perching dragonfly that attacks prey nearly as large as itself, including other dragonflies, and changes from bright green to powder blue as it matures. Read the guide →
Mammals EN Eastern Quoll Dasyurus viverrinus The eastern quoll vanished from mainland Australia for over 50 years before reintroduction programs began restoring wild populations there in recent years. Read the guide →
Mammals LC Eastern Rock Sengi Elephantulus myurus The eastern rock sengi patrols a network of cleared trails across rocky outcrops, memorising every twist and turn so it can escape at full speed the instant danger appears. Read the guide →
Birds VU Eastern Rockhopper Penguin Eudyptes filholi The eastern rockhopper penguin was split from its southern relative as a distinct species, breeding on sub-Antarctic islands scattered across the southern Indian Ocean. Read the guide →
Birds LC Eastern Screech-Owl Megascops asio The eastern screech-owl comes in two colour forms, grey and reddish, within the same population, and it sometimes brings live blind snakes back to the nest to protect its chicks from parasites. Read the guide →
Amphibians LC Eastern Spadefoot Scaphiopus holbrookii The eastern spadefoot is a toad that spends most of its life buried in sand, digging backward with a spade on each hind foot, and surfaces to breed only after heavy rain. Read the guide →
Mammals VU Eastern Spotted Skunk Spilogale putorius The eastern spotted skunk performs a handstand before spraying, a dramatic warning display from a smaller, more agile relative of the striped skunk that has declined sharply across much of its range. Read the guide →
Invertebrates LC Eastern Subterranean Termite Reticulitermes flavipes The eastern subterranean termite builds mud shelter tubes to travel above ground, since a colony must stay in contact with damp soil, making it North America's most economically damaging termite. Read the guide →
Invertebrates LC Eastern Tent Caterpillar Malacosoma americanum The eastern tent caterpillar builds a silken communal tent in the fork of a tree branch, a shared shelter that hundreds of siblings return to between feeding trips across the surrounding foliage. Read the guide →
Invertebrates LC Eastern Tiger Swallowtail Papilio glaucus The eastern tiger swallowtail wears different disguises across its life — bird-dropping caterpillar, false snake eyes, then a tiger-striped adult with decoy tails on its wings. Read the guide →
Birds LC Eastern Towhee Pipilo erythrophthalmus The eastern towhee forages with a distinctive two-footed backward kick that flings leaf litter aside, uncovering seeds and insects most ground-feeding birds would simply walk past. Read the guide →
Reptiles LC Eastern Water Dragon Intellagama lesueurii The eastern water dragon is a large Australian lizard of rivers and parks, a strong swimmer that dives to escape danger, with orange-chested males and eggs whose sex depends on temperature. Read the guide →
Birds LC Eastern Whipbird Psophodes olivaceus The eastern whipbird produces one of the most convincing illusions in the Australian bush, a male and female duetting so precisely together that the pair sounds like one bird cracking a single whip. Read the guide →
Birds LC Eastern Wood-Pewee Contopus virens The eastern wood-pewee sings a slow, plaintive "pee-a-wee" from a dead branch, then sits motionless for long stretches between short flights after passing insects. Read the guide →
Reptiles LC Eastern Worm Snake Carphophis amoenus The eastern worm snake spends nearly its entire life underground feeding on earthworms, its tiny eyes and smooth, glossy scales built for pushing through soil rather than for seeing where it's going. Read the guide →
Invertebrates LC Ebony Jewelwing Calopteryx maculata The ebony jewelwing flies with a slow, fluttering wingbeat, its solid black wings and metallic green body making it look more like a flying jewel than an insect. Read the guide →
Mammals LC Echidna Tachyglossus aculeatus The echidna is a spine-covered, egg-laying mammal that has no teeth, senses prey by electric field, and can lower its body temperature almost to freezing. Learn how this ancient oddity survives. Read the guide →
Birds LC Eclectus Parrot Eclectus roratus The eclectus parrot shows such extreme sexual dimorphism between bright green males and deep red-and-purple females that the two sexes were originally described as entirely different species. Read the guide →
Invertebrates NE Edible Crab Cancer pagurus The edible crab is a large, reddish-brown crab with a pie-crust shell edge and black-tipped claws, a powerful shell-cracker of northeast Atlantic rocky seas and a valuable European shellfish. Read the guide →
Mammals LC Edible Dormouse Glis glis The edible dormouse can hibernate for up to eleven months of the year, one of the longest hibernation periods of any mammal, waking for only a brief active season. Read the guide →
Amphibians LC Edible Frog Pelophylax kl. esculentus The edible frog is not a true species but a hybrid of two other frogs, reproducing by discarding half its own genome each generation and borrowing a fresh copy from a parent species. Read the guide →
Fish NE Eel Anguilliformes An eel is a snake-shaped fish that begins life as a transparent, leaf-shaped larva, and the freshwater kinds grow for years in rivers before crossing the open ocean to spawn once and die. Read the guide →
Invertebrates NE Egg Yolk Jelly Phacellophora camtschatica The egg yolk jelly has a yellow, bulging centre surrounded by a pale bell, resembling a fried egg, and often carries hitchhiking crabs and juvenile fish sheltering safely among its tentacles. Read the guide →
Reptiles LC Egg-eating Snake Dasypeltis scabra The African egg-eating snake has almost no teeth. It swallows a bird's egg wider than its own head, cracks the shell with bony spurs on its backbone, drinks the contents, and spits out a folded husk. Read the guide →
Reptiles LC Egyptian Cobra Naja haje The Egyptian cobra is one of Africa's largest cobra species, long linked to ancient Egypt through the rearing, hooded cobra symbol worn on pharaohs' crowns. Read the guide →
Mammals LC Egyptian Fruit Bat Rousettus aegyptiacus The Egyptian fruit bat is one of the only fruit bats that echolocates, clicking its tongue to navigate pitch-black caves where thousands roost together by day. Read the guide →
Mammals LC Egyptian Mongoose Herpestes ichneumon The Egyptian mongoose is the only mongoose species established wild in Europe, valued for centuries as a natural controller of snakes and rodents around human settlements. Read the guide →
Mammals LC Egyptian Spiny Mouse Acomys cahirinus The Egyptian spiny mouse has stiff, spine-like hairs on its back and a remarkable ability to shed its skin and heal wounds with very little scarring. Read the guide →
Mammals LC Egyptian Tomb Bat Taphozous perforatus The Egyptian tomb bat is a fast-flying insect hunter of Africa and Arabia that roosts in ancient tombs, ruins, caves, and mines, and forages high over open country. Read the guide →
Reptiles CR Egyptian Tortoise Testudo kleinmanni The Egyptian tortoise is the smallest tortoise in the Mediterranean region, a pale, tiny desert species of Libya and Egypt that has been collected for the pet trade and is now Critically Endangered. Read the guide →
Birds EN Egyptian Vulture Neophron percnopterus The Egyptian vulture is one of the very few birds that uses a tool, throwing a stone at an ostrich egg to crack the shell. Its bare yellow face is stained by the dung it eats. Read the guide →
Mammals LC Eland Taurotragus oryx The eland is the largest antelope in the world, a spiral-horned giant whose leg tendons click audibly with every step, still able to clear fences nearly three metres high. Read the guide →
Reptiles CR Electric Blue Day Gecko Lygodactylus williamsi The electric blue day gecko survives only within a few small patches of forest in Tanzania, a vividly coloured lizard whose entire wild population fits inside an area smaller than most towns. Read the guide →
Fish LC Electric Catfish Malapteruridae The electric catfish can deliver a shock of over 350 volts from an electric organ wrapped like a jacket around its whole body. Ancient Egyptians carved it on tomb walls 5,000 years ago. Read the guide →
Fish LC Electric Eel Electrophorus electricus The electric eel is not an eel but a knifefish that generates up to 860 volts — the strongest electric discharge of any animal. Learn how it stuns prey, breathes air, and leaps to shock threats. Read the guide →
Fish DD Electric Ray Torpediniformes The electric ray stuns prey and predators with a jolt from two organs in its disc that can deliver 45 volts or more. The word 'torpedo' comes from the Latin for the numbness its shock causes. Read the guide →
Fish LC Electric Yellow Cichlid Labidochromis caeruleus The electric yellow cichlid glows a solid, almost fluorescent yellow across its entire body, one of the most recognisable of the rock-dwelling mbuna cichlids endemic to Africa's Lake Malawi. Read the guide →
Birds LC Elegant Crested-tinamou Eudromia elegans The elegant crested-tinamou sports a thin, forward-curving crest and is among the most common ground birds of the Patagonian steppe, relying on camouflage and short flights to avoid predators. Read the guide →
Birds NT Elegant Tern Thalasseus elegans The elegant tern breeds at only a small handful of colonies off the Pacific coast of Mexico, concentrating much of its global population into a few sites before dispersing along the coast. Read the guide →
Invertebrates NE Elephant Beetle Megasoma elephas The elephant beetle is one of the bulkiest beetles in the world, with males carrying a pair of large horns used to wrestle rivals off rotting logs during disputes over mates. Read the guide →
Birds EX Elephant Bird Aepyornis maximus The elephant bird of Madagascar was the largest bird that ever lived, up to three metres tall, and it laid the biggest eggs of any animal in history. It vanished around a thousand years ago. Read the guide →
Fish LC Elephant Fish Callorhinchus milii The elephant fish uses a long, flexible, trunk-like snout packed with electroreceptors to detect buried prey in the sand, a chimaera relative of sharks that lays distinctive spiral egg cases. Read the guide →
Invertebrates LC Elephant Hawk-moth Deilephila elpenor The elephant hawk-moth's caterpillar has a trunk-like front end that gives the species its name, and inflates two false eyespots to mimic a small snake when threatened. Read the guide →
Reptiles LC Elephant Trunk Snake Acrochordus javanicus The elephant trunk snake is a wholly aquatic Southeast Asian snake with baggy, warty skin several sizes too big for it. It grips slippery fish with its file-like scales and is nearly helpless on land. Read the guide →
Invertebrates NE Elephant Weevil Orthorhinus cylindrirostris The elephant weevil carries an unusually long, downward-curving snout used to bore precise holes into wood for laying eggs, resembling a miniature elephant's trunk. Read the guide →
Fish LC Elephantnose Fish Gnathonemus petersii The elephantnose fish navigates muddy African rivers by generating a weak electric field and reading the distortions in it. It has one of the largest brains for its size of any animal. Read the guide →
Birds LC Elf Owl Micrathene whitneyi The elf owl is the smallest owl in the world, barely bigger than a sparrow and light enough to nest in a woodpecker hole in a saguaro cactus, hunting moths and scorpions on the wing. Read the guide →
Mammals LC Elk Cervus canadensis The elk, or wapiti, is one of the largest deer in the world, a North American and Central Asian herd animal whose bulls grow sweeping antlers each year and bugle through the autumn rut. Read the guide →
Invertebrates CR Elkhorn Coral Acropora palmata Elkhorn coral once formed the backbone of Caribbean reef crests, its broad, flattened branches absorbing breaking waves so effectively that whole coastlines depended on the structure it built. Read the guide →
Birds NT Elliot's Pheasant Syrmaticus ellioti Elliot's pheasant shares its genus and long trailing tail with Reeves's pheasant, but wears a chestnut-and-grey pattern instead of gold, restricted to hill forest in eastern China. Read the guide →
Birds LC Elliot's Storm-petrel Oceanites gracilis Elliot's storm-petrel forages close to shore along the cold Humboldt Current, one of the smallest storm-petrel species and among the very few seen regularly from land rather than far out at sea. Read the guide →
Reptiles CR Elongated Tortoise Indotestudo elongata The elongated tortoise is a yellowish, oblong-shelled forest tortoise of Asia that eats fruit, leaves, and even mushrooms, and is Critically Endangered through harvest for food and trade. Read the guide →
Amphibians LC Emerald Glass Frog Espadarana prosoblepon The emerald glass frog has skin translucent enough along its belly to reveal its own beating heart, a small green rainforest amphibian named for exactly what it lets you see through. Read the guide →
Fish LC Emerald Rockcod Trematomus bernacchii The emerald rockcod is one of the most common fish species found along the Antarctic coastline, living almost its entire life within a small home range on the shallow seafloor. Read the guide →
Fish LC Emerald Shiner Notropis atherinoides The emerald shiner forms schools numbering in the millions in large lakes and rivers, making it one of the most important single forage fish supporting entire freshwater food webs. Read the guide →
Birds LC Emerald Toucanet Aulacorhynchus prasinus The emerald toucanet trades the bold colours of its larger relatives for a green body that blends almost seamlessly into cloud forest foliage. Read the guide →
Reptiles LC Emerald Tree Boa Corallus caninus The emerald tree boa spends nearly its life coiled in the same saddle position on a branch, vivid green with a white zigzag pattern, hunting via heat-sensing pits along its jaw. Read the guide →
Fish LC Emperor Angelfish Pomacanthus imperator The emperor angelfish changes so completely with age that juveniles and adults look like different species, trading a dark blue body ringed in white for bold yellow-and-blue stripes. Read the guide →
Invertebrates LC Emperor Dragonfly Anax imperator The emperor dragonfly is one of the largest and fastest dragonfly species in Europe, patrolling ponds in powerful, continuous flight while hunting other flying insects out of the air. Read the guide →
Invertebrates NE Emperor Moth Saturnia pavonia The emperor moth is a large European moth of heaths and moorland whose males fly by day and track a female's scent from far away, and whose wings carry huge eyespots. Read the guide →
Amphibians NT Emperor Newt Tylototriton shanjing The emperor newt wears warning colours — a black body ridged with orange bumps that each sit over a poison gland. Threatened, it can swing sharpened ribs out through those bumps to jab an attacker. Read the guide →
Birds NT Emperor Penguin Aptenodytes forsteri The emperor penguin breeds through the Antarctic winter, the harshest conditions any bird faces. Learn how males incubate eggs at −40 °C and why sea ice loss threatens the species. Read the guide →
Invertebrates LC Emperor Scorpion Pandinus imperator The emperor scorpion is one of the largest scorpions on Earth, yet its sting is milder than a bee's — it kills with its massive pincers instead. Learn why it glows under UV and carries its young. Read the guide →
Mammals LC Emperor Tamarin Saguinus imperator The emperor tamarin was named for a flowing white moustache that reminded 19th-century naturalists of a German emperor's own famously styled facial hair. Read the guide →
Birds LC Emu Dromaius novaehollandiae The emu is the world's second-tallest bird, a flightless Australian nomad that can sprint at 50 km/h, go weeks without eating, and leaves the male to incubate the eggs and raise the chicks alone. Read the guide →
Fish EN Endler's Livebearer Poecilia wingei Endler's livebearer is naturally restricted to just a couple of small lagoons in Venezuela, a vividly coloured relative of the guppy now far more common in aquariums than in the wild. Read the guide →
Amphibians LC Ensatina Ensatina eschscholtzii The ensatina forms a famous ring species around California's Central Valley, where neighbouring populations interbreed but the two ends of the ring cannot. It has no lungs, breathing through its skin. Read the guide →
Fish LC Epaulette Shark Hemiscyllium ocellatum The epaulette shark is a small reef shark that walks across coral and tide pools on its fins, can leave the water for over an hour, and survives near-zero oxygen by shutting down its brain. Read the guide →
Mammals LC Epauletted Fruit Bat Epomophorus The male epauletted fruit bat inflates loud throat sacs and flashes tufts of white shoulder fur to attract females, a nightly calling display held in trees across the African savanna. Read the guide →
Birds EN Erect-crested Penguin Eudyptes sclateri The erect-crested penguin has stiff, upright yellow crests rather than drooping ones like its closest relatives, and its population has collapsed by over 70 percent in recent decades. Read the guide →
Reptiles LC Escambia Map Turtle Graptemys ernsti The Escambia map turtle was only formally recognized as its own species in 1992, split from a similar-looking relative after closer study revealed genuinely distinct shell and jaw features. Read the guide →
Mammals LC Etruscan Shrew Suncus etruscus The Etruscan shrew is the smallest mammal on Earth by body mass, weighing about as much as a large coin, with a heart that can beat more than a thousand times per minute. Read the guide →
Fish NT Eulachon Thaleichthys pacificus The eulachon is so extraordinarily oily that dried specimens could be fitted with a wick and burned as a candle, a small anadromous fish long central to Pacific Northwest Indigenous trade. Read the guide →
Birds LC Euphonia Euphonia A euphonia is a small, brightly coloured songbird that feeds heavily on mistletoe berries and, unusually for a bird, both parents share incubation duty rather than leaving it to the female alone. Read the guide →
Birds LC Eurasian Bullfinch Pyrrhula pyrrhula The Eurasian bullfinch can learn to mimic simple tunes taught to it in captivity, a trainable trait once celebrated in caged piping bullfinches. Read the guide →
Birds LC Eurasian Coot Fulica atra The Eurasian coot carries a bright white frontal shield above its bill, a feature so recognisable it inspired the phrase "as bald as a coot" for its stark, feather-free forehead. Read the guide →
Mammals LC Eurasian Harvest Mouse Micromys minutus The Eurasian harvest mouse weaves a spherical nest suspended among grass stems, using a prehensile tail to climb as one of the smallest rodents in the world. Read the guide →
Birds LC Eurasian Hoopoe Upupa epops The hoopoe is a pink, black, and white bird with a fanning crest, named for its "oop-oop-oop" call. Its nestlings and brooding female defend the nest with a foul secretion and projectile faeces. Read the guide →
Mammals LC Eurasian Lynx Lynx lynx The Eurasian lynx is the largest lynx species and Europe's third-largest predator — a solitary forest cat that hunts roe deer, was wiped out across much of Europe, and is now being brought back. Read the guide →
Birds LC Eurasian Magpie Pica pica The Eurasian magpie is a bold black-and-white crow relative with an outsize brain; it is one of the few animals to recognise itself in a mirror, and folklore ties it to luck, theft, and prophecy. Read the guide →
Mammals LC Eurasian Otter Lutra lutra The Eurasian otter recovered dramatically after near-extinction from pollution across much of Europe, now serving as a living indicator of healthy river water quality wherever it returns. Read the guide →
Mammals LC Eurasian Pygmy Shrew Sorex minutus The Eurasian pygmy shrew is one of the smallest mammals in Europe, weighing barely as much as a coin, yet it is bold enough to attack and kill insects larger than itself. Read the guide →
Mammals LC Eurasian Red Squirrel Sciurus vulgaris The Eurasian red squirrel has been pushed out of much of Britain by introduced grey squirrels, which outcompete it for food and carry a virus fatal only to reds. Read the guide →
Birds LC Eurasian Siskin Spinus spinus The Eurasian siskin hangs upside down from branch tips to feed, an acrobatic habit that lets it reach seed cones most other finches cannot access. Read the guide →
Mammals LC Eurasian Water Shrew Neomys fodiens The Eurasian water shrew is one of the very few venomous mammals alive, delivering a mild toxin through its bite that can subdue prey considerably larger than itself. Read the guide →
Reptiles LC European Adder Vipera berus The European adder is the most widespread snake in the world and the only venomous snake native to Britain, a zigzag-backed viper ranging from Western Europe to the Pacific. Read the guide →
Mammals LC European Badger Meles meles The European badger digs enormous underground burrow systems called setts that can be used by successive generations for centuries, one of the most sociable members of the weasel family. Read the guide →
Fish LC European Barracuda Sphyraena sphyraena The European barracuda is a long, silvery, fanged predator of the Mediterranean and eastern Atlantic with a jutting lower jaw, which hunts in shoals when young and alone when large. Read the guide →
Fish LC European Bitterling Rhodeus amarus The European bitterling is a tiny, iridescent carp relative whose female lays her eggs inside the gills of a living freshwater mussel, which then shelters the young fish while they grow. Read the guide →
Fish LC European Bullhead Cottus gobio The European bullhead, or miller's thumb, is a flat-headed, big-mouthed little fish that lurks under stones in clear streams, ambushing invertebrates, and whose male guards the eggs in his rocky nest. Read the guide →
Amphibians NT European Cave Salamander Hydromantes strinatii The European cave salamander fires a projectile tongue nearly as long as its own body inside limestone caves, a lungless hunter that breathes through skin too delicate to leave its damp home. Read the guide →
Fish CR European Eel Anguilla anguilla The European eel is born in the Sargasso Sea, drifts to Europe as a glass eel, spends decades in rivers, then swims 5,000 km back to spawn once and die. It is now Critically Endangered. Read the guide →
Amphibians LC European Fire-bellied Toad Bombina bombina When threatened, the European fire-bellied toad arches its back and turns up its feet to flash the vivid orange-and-black warning on its belly, a posture called the unken reflex. Read the guide →
Invertebrates NE European Flat Oyster Ostrea edulis The European flat oyster is a round, rough-shelled bivalve that once formed vast reefs in European seas, broods its larvae before release, and is now the subject of restoration projects. Read the guide →
Fish LC European Garfish Belone belone The European garfish is a slender, silvery, needle-jawed surface fish of the north-eastern Atlantic that leaps from the water, arrives in northern seas in spring, and has harmless bright green bones. Read the guide →
Birds LC European Goldfinch Carduelis carduelis The European goldfinch has a bill fine enough to extract seeds from thistles and teasels that most other birds simply cannot reach. Read the guide →
Reptiles LC European Green Lizard Lacerta viridis The European green lizard is a bright green, speckled lizard of sunny scrub and forest edges in central and southeastern Europe, whose males turn bright blue at the throat in the breeding season. Read the guide →
Fish LC European Hake Merluccius merluccius The European hake is a slim, silvery, large-mouthed night hunter of the north-eastern Atlantic shelf that rises from the sea bed to feed on shoaling fish and squid, and a favourite food fish of Spain. Read the guide →
Mammals CR European Hamster Cricetus cricetus The European hamster is a large, boldly three-coloured farmland rodent with a black belly, once a common crop pest and now Critically Endangered across much of its range. Read the guide →
Mammals NT European Hedgehog Erinaceus europaeus The European hedgehog carries about 5,000 spines, curls into an impregnable ball, hibernates for up to five months, and is now declining across Britain. Read the guide →
Invertebrates NE European Hornet Vespa crabro The European hornet is the largest social wasp of Europe, a brown-and-yellow insect that hunts other insects, flies at night as well as by day, and is far less aggressive than its reputation suggests. Read the guide →
Invertebrates LC European Lobster Homarus gammarus The European lobster is a blue-black, long-lived, clawed crustacean of north-eastern Atlantic rocky seabeds that hides in crevices by day, hunts at night, and turns red only when it is cooked. Read the guide →
Mammals CR European Mink Mustela lutreola The European mink has been pushed toward extinction largely by its own invasive American relative, escaped fur-farm animals that outcompete it wherever the two species overlap. Read the guide →
Fish LC European Perch Perca fluviatilis The European perch is a striped, spiny-finned predator of lakes and slow rivers across Europe and northern Asia that shoals when young and turns to solitary ambush hunting when old. Read the guide →
Mammals LC European Pine Marten Martes martes The European pine marten's recovery in Britain has helped native red squirrels bounce back, since martens prey on the invasive grey squirrels that outcompete and displace them. Read the guide →
Fish LC European Plaice Pleuronectes platessa The European plaice is a smooth, brown, orange-spotted flatfish of north-eastern Atlantic sands that crunches shellfish, starts life as a symmetrical larva, and is a key food fish of the North Sea. Read the guide →
Mammals LC European Polecat Mustela putorius The European polecat is the wild ancestor of the domestic ferret, a dark-masked mustelid that releases a powerful defensive musk when threatened. Read the guide →
Reptiles NT European Pond Turtle Emys orbicularis The European pond turtle is a long-lived freshwater turtle with a dark, yellow-speckled shell, found in ponds and marshes across Europe, and threatened by habitat loss and invasive sliders. Read the guide →
Birds LC European Robin Erithacus rubecula The European robin is a small, round, orange-breasted bird that is tame in British gardens, fiercely territorial year-round, and a leading model for how birds sense the Earth's magnetic field. Read the guide →
Fish LC European Sea Bass Dicentrarchus labrax The European sea bass is a silvery, spiny-finned predator of the north-eastern Atlantic and Mediterranean, prized by anglers and chefs, slow to mature, and now managed with catch limits. Read the guide →
Fish LC European Smelt Osmerus eperlanus The European smelt, or sparling, is a slender, silvery fish of estuaries and coasts that smells strongly of cucumber, runs up rivers to spawn in spring, and is prey for many larger fish and birds. Read the guide →
Invertebrates VU European Spiny Lobster Palinurus elephas The European spiny lobster is a clawless, reddish-brown, spiny-antennaed lobster of rocky Atlantic and Mediterranean seabeds that rasps its antennae to make sound and has been heavily overfished. Read the guide →
Invertebrates LC European Squid Loligo vulgaris The European squid is a torpedo-shaped, colour-changing cephalopod of the north-eastern Atlantic and Mediterranean that jets through the water, hunts fish and crustaceans, and lives only a few years. Read the guide →
Invertebrates NT European Stag Beetle Lucanus cervus The male European stag beetle has jaws shaped like a stag's antlers, half its body length, used to wrestle rivals. Its grub eats rotten wood underground for years before the brief adult emerges. Read the guide →
Amphibians LC European Tree Frog Hyla arborea The European tree frog is a small, bright green climbing frog of mainland Europe that spends warm days basking on leaves and fills spring nights with a loud rasping chorus. Read the guide →
Mammals LC European Wildcat Felis silvestris The European wildcat looks like a stocky, thick-furred tabby with a blunt, black-ringed tail, a genuinely wild species that is threatened mainly by interbreeding with domestic cats. Read the guide →
Mammals LC Evening Bat Nycticeius humeralis The evening bat emerges earlier than many other bat species, often while there is still light in the sky, a small hunter raising young in tree cavities and Spanish moss across the Southeast. Read the guide →
Birds VU Evening Grosbeak Coccothraustes vespertinus The evening grosbeak has lost more than 90 percent of its population in recent decades, one of the steepest declines of any North American bird. Read the guide →
Amphibians LC Everglades Dwarf Siren Pseudobranchus axanthus belli The Everglades dwarf siren is a tiny, eel-like salamander of Florida's marshes, so small and secretive that most people sharing its wetlands have never seen one despite it being locally common. Read the guide →
Fish LC Everglades Pygmy Sunfish Elassoma evergladei The Everglades pygmy sunfish thrives in some of the most crowded, vegetation-packed wetland water in Florida, a tiny predator so small that a single adult could rest comfortably across a fingertip. Read the guide →
Invertebrates LC Eyed Click Beetle Alaus oculatus The eyed click beetle wears two large fake eyespots on its back, and if flipped onto its back for real, snaps a spring-loaded hinge to flip itself upright with an audible click. Read the guide →
Reptiles LC Eyelash Viper Bothriechis schlegelii The eyelash viper is a small, vividly coloured tree snake with spiny "eyelash" scales over each eye. It comes in gold, green, pink, and grey, and ambushes hummingbirds and frogs from a branch. Read the guide →
Fish DD Faceless Fish Typhlonus nasus The faceless fish has no visible eyes at all from the front, its mouth tucked underneath its body, a rarely seen deep-sea species that went unrecorded for over a century between sightings. Read the guide →
Birds LC Fairy Prion Pachyptila turtur The fairy prion is the smallest prion species, filtering tiny plankton from the sea surface and visiting its burrow only under cover of darkness to avoid predatory skuas and gulls. Read the guide →
Invertebrates NE Fairy Shrimp Anostraca A fairy shrimp is a delicate crustacean that swims upside down through temporary pools, filtering food with rows of beating legs, and whose eggs survive dry in the soil for decades between rains. Read the guide →
Birds VU Fairy Tern Sternula nereis The fairy tern is one of the smallest terns in the world, nesting in shallow scrapes on open beaches across Australia and New Zealand, leaving its eggs highly exposed to disturbance. Read the guide →
Fish LC Fairy Wrasse Cirrhilabrus The fairy wrasse flashes intense courtship colours as males compete for a female's attention, forming harem groups across Indo-Pacific reefs in a dazzling display of colour. Read the guide →
Mammals EN Falanouc Eupleres goudotii The falanouc is one of the few carnivores that barely hunts vertebrates at all, a Madagascar specialist with reduced, peg-like teeth built almost entirely for eating earthworms. Read the guide →
Birds NE Falcon Falconidae A falcon is a fast, pointed-winged bird of prey that kills with a notched beak as well as its feet, is not closely related to hawks, and in the peregrine hits the highest speed of any animal. Read the guide →
Birds LC Falkland Steamer Duck Tachyeres brachypterus The Falkland steamer duck is a heavily built, flightless waterfowl endemic to the Falkland Islands, churning across the water with rapid wingbeats in a motion resembling a paddle steamer. Read the guide →
Mammals LC Fallow Deer Dama dama The fallow deer grows broad, flattened antlers unlike the branching spikes of most other deer, a spotted species spread across Europe by the Romans and Normans. Read the guide →
Reptiles EN False Gharial Tomistoma schlegelii The false gharial has the same long, narrow, fish-catching snout as the true gharial despite belonging to a separate crocodilian family, two unrelated lineages arriving at the same solution. Read the guide →
Mammals NT False Killer Whale Pseudorca crassidens The false killer whale has been documented sharing food with divers and other dolphins, a large, social family member named for a superficial skull resemblance to the orca, not a close relation. Read the guide →
Reptiles LC False Map Turtle Graptemys pseudogeographica The false map turtle earned its odd name for resembling the common map turtle, distinguished by a bold yellow crescent behind each eye and a low, saw-toothed ridge running down its shell. Read the guide →
Invertebrates LC Fan Worm Sabellidae A fan worm builds a soft tube to live in and filter-feeds through a beautiful, feathery crown of tentacles that can vanish back into the tube in a fraction of a second at the slightest disturbance. Read the guide →
Mammals NT Fanaloka Fossa fanaloka The fanaloka looks like a civet but belongs to a family of carnivores found only on Madagascar, more closely related to the mongoose-like fossa than to any true civet. Read the guide →
Fish LC Fanfin Anglerfish Caulophryne jordani The fanfin anglerfish trails extraordinarily long, thin, filament-covered fin rays through the water, thought to sense the faintest vibrations of nearby prey in the total darkness of the deep sea. Read the guide →
Amphibians LC Fanged Frog Limnonectes larvaepartus The male fanged frog has a pair of bony tusks on its lower jaw for fighting rivals. This Sulawesi species is the only frog known to give birth to live tadpoles rather than laying eggs. Read the guide →
Fish LC Fangtooth Anoplogaster cornuta The fangtooth has the largest teeth relative to body size of any fish, so long the lower pair slot into sockets in its skull to let it close its mouth. Despite the look, it is barely 16 cm long. Read the guide →
Fish LC Fantail Darter Etheostoma flabellare The fantail darter's breeding males carry fleshy knobs on their dorsal fin spines, possibly mimicking eggs, and guard a nest glued upside down to the underside of a rock. Read the guide →
Birds LC Fasciated Antshrike Cymbilaimus lineatus The fasciated antshrike wears fine black-and-white barring across its entire body, a striking pattern usually hidden deep within tangled vine thickets. Read the guide →
Mammals LC Fat Sand Rat Psammomys obesus The fat sand rat lives almost entirely on salty, succulent desert plants, and on ordinary rodent food it readily becomes obese and diabetic, making it a model animal for diabetes research. Read the guide →
Mammals LC Fat-Tailed Dunnart Sminthopsis crassicaudata The fat-tailed dunnart stores emergency energy reserves in its tail and is the closest living relative researchers are using in an attempt to revive the extinct thylacine. Read the guide →
Mammals LC Fat-tailed Dwarf Lemur Cheirogaleus medius The fat-tailed dwarf lemur stores fat in its tail and hibernates for months in a tree hole, the only primate known to spend part of the year in true hibernation. Read the guide →
Reptiles LC Fat-Tailed Gecko Hemitheconyx caudicinctus The fat-tailed gecko stores emergency energy reserves directly in its tail, which visibly swells with fat and can be drawn on during lean periods when food is scarce. Read the guide →
Mammals LC Fat-tailed Gerbil Pachyuromys duprasi The fat-tailed gerbil stores energy in a short, club-shaped tail, a docile, nocturnal rodent of the northern Sahara and nearby deserts. Read the guide →
Fish LC Fathead Minnow Pimephales promelas The fathead minnow has become one of the most important fish in scientific research worldwide, with breeding males developing a fatty head pad and guarding eggs alone in a nest they clean for weeks. Read the guide →
Invertebrates LC Feather Duster Worm Sabellidae The feather duster worm builds a soft, flexible tube and extends a feathery crown of tentacles to filter food from the water, vanishing instantly inside at the first hint of a passing shadow. Read the guide →
Invertebrates NE Feather Star Crinoidea The feather star is a living relative of the sea lilies, an ancient echinoderm with dozens of feathery filtering arms that crawls on tiny jointed legs and can swim by flailing its arms. Read the guide →
Mammals LC Feathertail Glider Acrobates pygmaeus The feathertail glider is the world's smallest gliding mammal, a mouse-sized marsupial that steers 25-metre glides with a stiff, feather-shaped tail and can run up a pane of glass. Read the guide →
Reptiles LC Fence Lizard Sceloporus A fence lizard is a common, spiny-scaled North American lizard known for its push-up display, and its blood contains a protein that kills the Lyme disease bacteria carried by ticks that feed on it. Read the guide →
Mammals LC Fennec Fox Vulpes zerda The fennec fox is the smallest wild canid and the one with the biggest ears relative to its body — radiators that dump heat and hear insects underground. Read the guide →
Reptiles LC Fer-de-lance Bothrops asper The fer-de-lance causes most serious snakebites in Central America — a large, fast-striking pit viper that thrives on farmland, hunts by heat, and delivers a big dose of tissue-destroying venom. Read the guide →
Birds LC Ferruginous Hawk Buteo regalis The ferruginous hawk is the largest soaring hawk in North America, its rusty, iron-coloured plumage matched by a diet built almost entirely around ground squirrels and prairie dogs. Read the guide →
Birds LC Ferruginous Pygmy Owl Glaucidium brasilianum The ferruginous pygmy owl is a fierce hunter despite its tiny size, often mobbed by day-active songbirds that recognize it as a genuine threat. Read the guide →
Invertebrates NE Fiddler Beetle Eupoecila australasiae The fiddler beetle carries a fiddle-shaped marking across its back, a patterned green-and-black flower beetle commonly seen feeding on native Australian blossoms. Read the guide →
Invertebrates NE Fiddler Crab Uca (and related genera) Male fiddler crabs have one claw so enlarged it can be a third of their body weight, waved in set patterns to court females and warn rivals. They sift mud for microbes and regrow a lost claw. Read the guide →
Invertebrates LC Field Cricket Gryllus campestris The field cricket is a large, glossy black cricket of warm grasslands that sings from the mouth of its own burrow in spring and is now one of the rarest insects in Britain. Read the guide →
Mammals LC Field Vole Microtus agrestis The field vole is a small, short-tailed grassland rodent that tunnels runways through rough grass, whose booming and crashing numbers feed owls, kestrels, and foxes across northern Europe. Read the guide →
Invertebrates LC Fiery Skipper Hylephila phylaeus The fiery skipper spreads north each summer from warmer year-round breeding grounds, unable to survive freezing winters but reliably recolonizing the same lawns and fields as temperatures allow. Read the guide →
Birds LC Fiery-billed Aracari Pteroglossus frantzii The fiery-billed aracari carries a bill in shades of glowing orange-red, a smaller, highly social toucan relative restricted to the Pacific slope forests of Costa Rica and Panama. Read the guide →
Invertebrates LC Fig Beetle Cotinis mutabilis The fig beetle flies with an audible, buzzing drone and often crashes into people or objects in its path, a heavy-bodied metallic green beetle drawn to overripe fruit through the warmer months. Read the guide →
Invertebrates NE Fig Wasp Blastophaga psenes The fig wasp is a pinhead-sized insect that can only breed inside a fig, and most fig species can only be pollinated by their own wasp. The female forces her way in, pollinates, lays eggs, and dies. Read the guide →
Fish NE Figure-8 Puffer Dichotomyctere ocellatus The figure-8 puffer carries a pattern of interlocking loops on its back resembling the numeral eight, a small brackish-water pufferfish that inflates sharply when threatened. Read the guide →
Reptiles EN Fiji Banded Iguana Brachylophus fasciatus The Fiji banded iguana is a vividly green, pale-striped lizard found only on a handful of South Pacific islands, and males can darken their banding during social encounters. Read the guide →
Reptiles CR Fiji Crested Iguana Brachylophus vitiensis The Fiji crested iguana is a brilliant emerald lizard banded with white, found on a few small dry-forest islands. Its eggs take up to nine months to hatch, the longest incubation known in any lizard. Read the guide →
Reptiles LC File Snake Acrochordus A file snake is a fully aquatic snake of Asian and Australian waters with loose, baggy skin and rough file-like scales it uses to grip slippery fish, and it is nearly helpless out of the water. Read the guide →
Fish LC Filefish Monacanthidae The filefish carries rough, sandpaper-like skin and a thin, leaf-shaped body that lets it sway convincingly among seagrass and soft coral, disappearing in plain sight. Read the guide →
Mammals VU Fin Whale Balaenoptera physalus The fin whale is the second-largest animal ever to have lived, trailing only the blue whale, a fast, slender baleen whale with one of nature's more unusual features, an asymmetrically coloured jaw. Read the guide →
Birds NE Finch Fringillidae A finch is a small songbird with a stout conical bill built for cracking seeds, and the true finches include the canary and the crossbill, whose bill tips cross to prise open conifer cones. Read the guide →
Birds VU Fiordland Penguin Eudyptes pachyrhynchus The Fiordland penguin nests in dense temperate rainforest rather than open coastline, one of the few penguin species to breed among ferns and moss-covered trees rather than bare rock or ice. Read the guide →
Invertebrates NE Fire Ant Solenopsis invicta The red imported fire ant swarms in the thousands and stings in unison, each ant pivoting on its jaws to sting repeatedly. Colonies link legs into living rafts that survive floods. Read the guide →
Invertebrates LC Fire Coral Millepora Fire coral looks like a true reef-building coral but is actually a close relative of jellyfish and the Portuguese man o' war, and its sting lives up to the name with a burn that can last for hours. Read the guide →
Amphibians LC Fire Salamander Salamandra salamandra The fire salamander wears black-and-yellow warning colours, squirts a nerve toxin from glands behind its eyes, and in some populations gives birth to live young. Learn about this striking amphibian. Read the guide →
Reptiles LC Fire Skink Mochlus fernandi The fire skink carries vivid bands of red, orange, and iridescent black-blue down its sides, a colourful West African lizard popular in the pet trade for its calmer-than-expected temperament. Read the guide →
Invertebrates LC Fire Urchin Asthenosoma The fire urchin advertises danger with a vivid, almost glowing colouration, and its venomous spines back up the warning with one of the most painful stings of any sea urchin. Read the guide →
Amphibians LC Fire-bellied Newt Cynops A fire-bellied newt is a small, largely aquatic East Asian newt, drab above and vivid orange or red below, whose skin carries the same nerve poison as a pufferfish, and it is a popular pet. Read the guide →
Amphibians LC Fire-bellied Toad Bombina A fire-bellied toad is a small Eurasian amphibian with a drab warty back and a vivid orange-and-black belly, which it flashes by arching into a back-bend to warn a predator of the toxin in its skin. Read the guide →
Birds LC Fire-eyed Diucon Xolmis pyrope The fire-eyed diucon hunts flying insects from an exposed perch, its startling red eyes making it one of the more distinctive tyrant flycatchers found anywhere in southern South America. Read the guide →
Invertebrates NE Firebug Pyrrhocoris apterus The firebug is a bright red-and-black bug whose warning colours advertise a bad taste, which gathers in large groups beneath lime trees and is often found mating end to end for hours. Read the guide →
Fish LC Firefish Goby Nemateleotris magnifica The firefish goby raises a tall, flag-like first dorsal fin above a body fading from pale white into vivid red, a signal flown from just above the burrow it darts into at the first sign of danger. Read the guide →
Invertebrates LC Firefly Photinus pyralis The firefly is a beetle that makes near-100%-efficient cold light in its abdomen to send coded flash signals for a mate. Some females mimic other species' codes to lure and eat the males that answer. Read the guide →
Invertebrates NE Firefly Squid Watasenia scintillans The firefly squid is a hand-sized deep-water squid covered in light organs. Each spring, millions surge into one bay in Japan to spawn, turning the water glowing blue before they die. Read the guide →
Fish LC Firemouth Cichlid Thorichthys meeki The firemouth cichlid flares an ember-coloured throat at rivals during territorial disputes, a bluffing display that usually settles conflicts before a single bite is thrown. Read the guide →
Mammals LC Fisher Pekania pennanti The fisher is one of the few predators able to hunt porcupines successfully, using speed and repeated bites to the face to overcome an animal that stops almost every other North American carnivore. Read the guide →
Mammals VU Fishing Cat Prionailurus viverrinus The fishing cat is a stocky, water-loving wild cat of South and Southeast Asian wetlands that dives and swims after fish, scoops them from the water with a paw, and has partly webbed feet. Read the guide →
Invertebrates LC Fishing Spider Dolomedes spp. The fishing spider walks on water using surface tension, dives underwater to escape danger, and detects prey by reading vibrations spreading across the surface. Read the guide →
Fish LC Five-bearded Rockling Ciliata mustela The five-bearded rockling is a slimy, eel-like, dark relative of the cod that lurks in rock pools and under stones on north-eastern Atlantic shores, sensing food with five fleshy barbels. Read the guide →
Reptiles LC Five-lined Skink Plestiodon fasciatus The five-lined skink is the common striped lizard of eastern North America whose young flash a brilliant blue tail, wrongly feared as a venomous scorpion, and whose females guard their eggs. Read the guide →
Fish LC Flagfish Jordanella floridae The flagfish is one of the few fish that will happily eat troublesome hair algae and blue-green algae most fish ignore, making it a favourite biological cleanup crew among aquarium keepers. Read the guide →
Invertebrates NE Flamboyant Cuttlefish Metasepia pfefferi The flamboyant cuttlefish is a palm-sized cuttlefish that walks the seabed on arm-tips, pulsing waves of yellow, red, and purple across its skin. Its flesh is toxic — the only cuttlefish known to be. Read the guide →
Fish LC Flame Angelfish Centropyge loricula The flame angelfish burns a vivid red-orange crossed by dark vertical bars, one of the smallest and most popular dwarf angelfish, hiding in reef rubble rather than patrolling open water. Read the guide →
Fish LC Flame Hawkfish Neocirrhites armatus The flame hawkfish burns a vivid, uniform red-orange across its entire body, sheltering among the branches of living coral it rarely strays far from. Read the guide →
Birds LC Flame-Colored Tanager Piranga bidentata The flame-colored tanager occasionally interbreeds with a closely related species where their mountain forest ranges overlap in Mexico. Read the guide →
Birds LC Flame-faced Tanager Tangara parzudakii The flame-faced tanager shows a blazing orange-red facial patch against green and black plumage, a striking resident of Andean cloud forest. Read the guide →
Birds LC Flamingo Phoenicopterus roseus The flamingo is a filter-feeding wading bird that eats with its head upside down, gets its pink colour entirely from its food, and breeds in colonies tens of thousands strong on caustic salt lakes. Read the guide →
Invertebrates LC Flamingo Tongue Snail Cyphoma gibbosum The flamingo tongue snail's vivid orange-spotted pattern isn't its shell at all, but living tissue that retracts to reveal a plain shell hidden underneath the whole time. Read the guide →
Reptiles LC Flap-footed Lizard Pygopodidae A flap-footed lizard is an Australian gecko relative that has lost its front legs entirely and kept only a pair of tiny flap-like flaps where its hind legs used to be. Read the guide →
Reptiles LC Flap-Necked Chameleon Chamaeleo dilepis The flap-necked chameleon flares skin flaps at the back of its head into a dramatic warning display, one of the most widespread chameleon species across sub-Saharan Africa. Read the guide →
Invertebrates DD Flapjack Octopus Opisthoteuthis californiana The flapjack octopus flattens into a pancake-like shape when its webbed arms spread wide, a soft, deep-sea relative of the dumbo octopus drifting gently above the seafloor. Read the guide →
Fish CR Flapper Skate Dipturus intermedius The flapper skate is one of the largest skates in the world, an olive-grey giant of the north-eastern Atlantic over two metres across, now critically endangered with a stronghold in western Scotland. Read the guide →
Fish LC Flashlight Fish Anomalops katoptron The flashlight fish carries a glowing organ full of light-making bacteria under each eye, blinks it on and off, and in schools of hundreds fills dark reef water with points of light. Read the guide →
Mammals EN Flat-headed Cat Prionailurus planiceps The flat-headed cat is a semi-aquatic Southeast Asian hunter with a long, flattened skull and fish-gripping teeth, one of the few cats that seeks out wetlands for its prey. Read the guide →
Reptiles NT Flat-Tailed Horned Lizard Phrynosoma mcallii The flat-tailed horned lizard is restricted to a small stretch of Sonoran and Colorado desert sand dunes, its unusually flattened, broad body providing extreme camouflage against fine wind-blown sand. Read the guide →
Reptiles DD Flatback Turtle Natator depressus The flatback turtle is the only sea turtle found nowhere but Australia, nesting solely on its northern beaches and staying within the shallow waters of the continental shelf for life. Read the guide →
Fish NE Flatfish Pleuronectiformes A flatfish lies on its side on the sea floor, and to get there it rebuilds its own head as a youngster, moving one eye over the skull so both end up on the upper side. Read the guide →
Fish LC Flathead Catfish Pylodictis olivaris The flathead catfish is a huge, flat-headed river catfish with a jutting lower jaw and mottled gold skin, a solitary night hunter that eats live fish and can pass 45 kg in its native waters. Read the guide →
Fish LC Flathead Chub Platygobio gracilis The flathead chub thrives in murky, sediment-heavy prairie rivers that many other fish avoid entirely, its flattened head and streamlined body suited to holding position against strong current. Read the guide →
Amphibians EN Flatwoods Salamander Ambystoma cingulatum The flatwoods salamander lays its eggs in a dry pond basin and waits for autumn rain to flood it, a gamble that has made it one of the most endangered amphibians in the eastern United States. Read the guide →
Invertebrates NE Flea Ctenocephalides felis The flea is a wingless, blood-sucking insect that can jump around fifty times its own length using a catapult of stored elastic energy. The rat flea carried the bacterium behind the Black Death. Read the guide →
Birds LC Flicker Colaptes spp. The flicker abandons the typical woodpecker habit of drilling into bark, instead hopping across open ground to dig ants directly out of the soil with a long, barbed tongue built for exactly that job. Read the guide →
Fish LC Flier Centrarchus macropterus The flier carries a dark eyespot on its dorsal fin and unusually long, rounded fins for a sunfish relative, favoring sluggish, heavily vegetated swamps of the southeastern coastal plain. Read the guide →
Fish LC Flier Sunfish Centrarchus macropterus The flier sunfish is the sole member of its own genus, a rounded, heavily barred fish carrying a dark eyespot near its dorsal fin that can help redirect a predator's strike away from vital organs. Read the guide →
Amphibians VU Florida Bog Frog Lithobates okaloosae The Florida bog frog is found in only a small handful of acidic seepage streams within a single county, one of the most geographically restricted frog species in the United States. Read the guide →
Reptiles LC Florida Crowned Snake Tantilla relicta The Florida crowned snake spends nearly its life hidden beneath leaf litter, a tiny, secretive predator of dry scrub and sandhill habitat that most residents never realise shares their own yard. Read the guide →
Fish LC Florida Gar Lepisosteus platyrhincus The Florida gar is found nowhere else on Earth but the Florida peninsula, an ambush predator armored in the same ancient diamond-scaled design shared across its entire long-lived family. Read the guide →
Reptiles LC Florida Red-Bellied Cooter Pseudemys nelsoni The Florida red-bellied cooter often basks stacked several deep on a single log, its reddish underside and domed shell making it one of the most recognisable turtles in Florida's lakes and rivers. Read the guide →
Reptiles VU Florida Scrub Lizard Sceloporus woodi The Florida scrub lizard survives only within Florida's disappearing scrub habitat, a naturally patchy, fire-dependent ecosystem now fragmented further by coastal development pressure. Read the guide →
Reptiles LC Florida Softshell Turtle Apalone ferox The Florida softshell turtle breathes through a long, flexible, snorkel-like nose while staying almost entirely buried in mud, and it bites hard enough to make handling one a genuinely bad idea. Read the guide →
Reptiles LC Florida Worm Lizard Rhineura floridana The Florida worm lizard is North America's only native amphisbaenian, a limbless reptile so wormlike it is often mistaken for an earthworm, moving backward underground as easily as forward. Read the guide →
Invertebrates NE Flower Hat Jelly Olindias formosus The flower hat jelly has translucent, striped tentacles that curl inward around its bell like petals, glowing faintly under ultraviolet light and delivering a sting painful enough to affect humans. Read the guide →
Invertebrates NE Flower Urchin Toxopneustes pileolus The flower urchin is an Indo-Pacific sea urchin whose short spines are hidden under a carpet of pink flower-like pincers that bite and inject venom, one of the most dangerous urchins to touch. Read the guide →
Fish NE Flowerhorn Cichlid Hybrid cichlid, no single wild species The flowerhorn cichlid is a man-made hybrid fish that does not exist in the wild, bred for a prominent head bump and vivid colours that some cultures consider symbols of good fortune. Read the guide →
Birds LC Flowerpecker Dicaeidae The flowerpecker keeps mistletoe populations alive by passing seeds through its gut in under an hour, a tiny nectar bird whose short digestive tract has become essential to a parasite's survival. Read the guide →
Invertebrates NE Fly Diptera A fly is an insect with a single pair of wings, the second pair shrunk to tiny balancing organs; the order holds the most agile insect fliers, along with the mosquito and the housefly. Read the guide →
Reptiles LC Flying Dragon Draco volans The flying dragon is a small Southeast Asian lizard that glides between tree trunks on "wings" made of skin stretched over greatly elongated ribs, which it folds flat against its body when not in use. Read the guide →
Fish LC Flying Fish Exocoetidae Flying fish escape predators by building speed underwater, bursting through the surface, and gliding on wing-like fins 50 metres at a time, then beating the water with the tail lobe to relaunch. Read the guide →
Amphibians NE Flying Frog Rhacophoridae A flying frog is an Asian and African tree frog that glides between trees on huge webbed feet; its family also holds the foam-nest frogs and the moss frogs that vanish against lichen. Read the guide →
Reptiles LC Flying Gecko Ptychozoon kuhli The flying gecko of Southeast Asia glides between rainforest trees on flaps of skin, webbed feet, and a fringed tail. Pressed flat on bark, the same flaps make it almost invisible. Read the guide →
Fish LC Flying Gurnard Dactylopterus volitans The flying gurnard spreads huge peacock-blue pectoral fins that look like wings but are used to startle predators, not to fly. It walks the seabed on finger-like fin rays, feeling for buried crabs. Read the guide →
Reptiles LC Flying Snake Chrysopelea A flying snake is a slender Asian tree snake that cannot truly fly but launches from a branch, flattens its body into a wing, and glides between trees, undulating in the air as if swimming. Read the guide →
Birds LC Flying Steamer Duck Tachyeres patachonicus The flying steamer duck is the only steamer duck species capable of true flight, setting it apart from several closely related, heavier-bodied relatives that have lost the ability entirely. Read the guide →
Amphibians LC Foam-nest Frog Chiromantis A foam-nest frog whips its eggs into a ball of froth on a branch above water, where the foam shields the tadpoles from sun and predators until they drop into the pool below. Read the guide →
Fish LC Football-fish Himantolophidae The football-fish is a round, spine-covered deep-sea anglerfish whose glowing lure draws prey close in total darkness, with males that remain free-living rather than fusing to a female. Read the guide →
Amphibians NT Foothill Yellow-Legged Frog Rana boylii The foothill yellow-legged frog times its breeding to a river's retreating floodwaters, laying eggs directly onto submerged rocks in current strong enough to sweep away lesser amphibians. Read the guide →
Reptiles LC Forest Cobra Naja melanoleuca The forest cobra is Africa's largest true cobra, a glossy black, swimming and tree-climbing snake of rainforest and wet savanna that hunts fish, amphibians, and snakes with a neurotoxic venom. Read the guide →
Birds LC Fork-tailed Drongo Dicrurus adsimilis The fork-tailed drongo is an African bird that makes a living by lying, giving false alarm calls to scare meerkats and birds off their food so it can dart in and steal it. Read the guide →
Birds LC Fork-tailed Woodnymph Thalurania furcata The fork-tailed woodnymph pairs a deep violet-blue body with a green back and a distinctly forked tail, one of the most common hummingbirds across the Amazon basin understory. Read the guide →
Mammals VU Fossa Cryptoprocta ferox The fossa is Madagascar's largest predator — a cat-like relative of the mongoose that climbs down trees head-first and hunts lemurs through the canopy. Read the guide →
Fish LC Four-Eyed Fish Anableps The four-eyed fish only has two eyes, but each one splits into an upper and lower half with its own focus, letting the fish watch for danger in the air and underwater at once. Read the guide →
Amphibians LC Four-eyed Frog Pleurodema thaul The four-eyed frog startles predators by arching its back to reveal two large eye-like markings on its rump, a bluff aimed squarely away from its actual head. Read the guide →
Mammals LC Four-eyed Opossum Philander opossum The four-eyed opossum carries two pale spots above its eyes that resemble a second pair, a nocturnal and solitary marsupial found across a broad stretch of the Americas. Read the guide →
Reptiles NT Four-lined Snake Elaphe quatuorlineata The four-lined snake is one of Europe's largest non-venomous snakes, a striped constrictor of dry Mediterranean scrub, and a star of an annual snake procession in the Italian village of Cocullo. Read the guide →
Mammals LC Four-toed Hedgehog Atelerix albiventris The four-toed hedgehog is the species behind nearly every pet hedgehog in the world, a small African savanna native whose hind feet carry four toes rather than the usual five. Read the guide →
Amphibians LC Four-toed Salamander Hemidactylium scutatum The four-toed salamander is a small lungless amphibian of mossy North American wetlands, named for a missing toe, with a break point at the base of its tail and a habit of nesting in shared clutches. Read the guide →
Mammals LC Four-Toed Sengi Petrodromus tetradactylus The four-toed sengi is missing a toe most of its relatives have, an unusual foot structure that gives the species both its common name and its place as the only member of its genus. Read the guide →
Amphibians VU Fourche Mountain Salamander Plethodon fourchensis The Fourche Mountain salamander survives only on a single ridge in the Ouachita range, sharing the same narrow-range pattern as several other lungless salamanders scattered across those mountains. Read the guide →
Amphibians LC Fowler's Toad Anaxyrus fowleri Fowler's toad is a common brown toad of the eastern United States, told apart from the American toad by its warty spots, plain belly, and a nasal, bleating call like a crying baby. Read the guide →
Mammals NE Fox Vulpini A fox is a small, lightly built member of the dog family that hunts alone rather than in a pack, eats almost anything, and has adapted better than almost any wild carnivore to living alongside people. Read the guide →
Birds LC Fox Sparrow Passerella iliaca The fox sparrow varies so dramatically across its range that some regional forms look like different species, unified mainly by a shared double-footed scratching habit and a rich, musical song. Read the guide →
Mammals LC Fox Squirrel Sciurus niger The fox squirrel is the largest tree squirrel in North America, its rich rust-orange colouring and size setting it apart from the smaller, greyer eastern gray squirrel it often shares habitat with. Read the guide →
Fish LC Foxface Rabbitfish Siganus vulpinus The foxface rabbitfish carries venomous spines along its fins strong enough to cause serious pain, hidden behind a strikingly patterned yellow body and an elongated, fox-like snout. Read the guide →
Mammals VU Franciscana Dolphin Pontoporia blainvillei The franciscana dolphin has the longest beak relative to body size of any cetacean, a small coastal species of a limited South Atlantic stretch frequently caught as accidental bycatch in fishing nets. Read the guide →
Mammals EN Francois' Langur Trachypithecus francoisi Francois' langur is an Endangered black-and-white monkey of limestone karst in southern China and northern Vietnam that sleeps in caves and ledges, and whose babies are born bright orange. Read the guide →
Invertebrates CR Franklin's Bumblebee Bombus franklini Franklin's bumblebee is a Critically Endangered bumblebee with one of the smallest ranges of any bee, in southern Oregon and northern California, and has not been seen since 2006. Read the guide →
Birds LC Franklin's Gull Leucophaeus pipixcan Franklin's gull breeds far from any ocean on prairie wetlands across the North American interior, following farm ploughs for insects so readily that it earned the nickname prairie dove. Read the guide →
Mammals LC Fraser's Dolphin Lagenodelphis hosei Fraser's dolphin went unrecognised for decades, known only from a single skeleton until living animals were documented at sea, a stocky, fast-swimming deep-water species with unusually small fins. Read the guide →
Fish NE Freshwater Angelfish Pterophyllum scalare A freshwater angelfish is a tall, disc-shaped Amazon cichlid, a long-standing aquarium favourite, and despite its graceful look it is an ambush predator that pairs off and guards its eggs fiercely. Read the guide →
Reptiles LC Freshwater Crocodile Crocodylus johnstoni The freshwater crocodile, or freshie, is a slender-snouted Australian crocodile of northern rivers that eats fish and insects, is far shyer than the saltwater crocodile, and was hit by cane toads. Read the guide →
Fish LC Freshwater Drum Aplodinotus grunniens The freshwater drum is the only croaker that lives entirely in fresh water, a bottom fish that grunts, crushes snails with its throat, and leaves behind lucky-stone ear bones. Read the guide →
Invertebrates NE Freshwater Jellyfish Craspedacusta sowerbii The freshwater jellyfish is a tiny, coin-sized, harmless jellyfish from China that has spread worldwide and appears in lakes and quarries in sudden summer blooms. Read the guide →
Invertebrates EN Freshwater Pearl Mussel Margaritifera margaritifera The freshwater pearl mussel is a dark, long-lived river mussel that can survive for well over a century, whose larvae live on salmon and trout gills, and which is now endangered across Europe. Read the guide →
Invertebrates NE Freshwater Shrimp Gammarus pulex The freshwater shrimp is a small, sideways-flattened, leaf-shredding crustacean of clean European streams that swims on its side, carries its mate before pairing, and signals good water quality. Read the guide →
Reptiles LC Frilled Lizard Chlamydosaurus kingii The frilled lizard of Australia and New Guinea snaps open a huge skin collar around its head when threatened, hisses, and sprints away on its hind legs — a bluff that is almost pure theatre. Read the guide →
Fish LC Frilled Shark Chlamydoselachus anguineus The frilled shark is an eel-like deep-sea shark with 300 backward-pointing trident teeth and a lineage barely changed for 80 million years. It may carry its young for over three years. Read the guide →
Mammals LC Fringe-lipped Bat Trachops cirrhosus The fringe-lipped bat finds frogs by eavesdropping on the males' mating calls, and can learn from other bats which croaks mean a safe meal and which belong to poisonous toads. Read the guide →
Reptiles VU Fringe-toed Lizard Uma A fringe-toed lizard has comb-like scales along its toes that act like built-in snowshoes for sand, letting it sprint across loose dunes and dive beneath the surface to vanish from predators. Read the guide →
Amphibians NE Frog Anura A frog is a tailless, jumping amphibian that starts life as a plant-eating tadpole in water, then becomes a meat-eating adult that breathes partly through its permeable skin. Read the guide →
Reptiles LC Frog-Eyed Gecko Teratoscincus The frog-eyed gecko carries unusually large, loose scales that it rubs together to produce a rattling warning sound, an unexpected defense borrowed, in effect, from a rattlesnake's own strategy. Read the guide →
Invertebrates NE Frog-legged Beetle Sagra buqueti The male frog-legged beetle carries dramatically enlarged, muscular hind legs resembling a frog's, used to wrestle rivals for access to mates on vine stems. Read the guide →
Fish LC Frogfish Antennariidae Frogfish are lumpy, near-motionless reef ambushers that disguise themselves as sponges or algae, dangle a built-in fishing lure, and swallow prey up to twice their own size in six milliseconds. Read the guide →
Invertebrates NE Froghopper Philaenus spumarius The froghopper is the insect behind the blobs of cuckoo spit on garden plants, and the adult can jump with an acceleration far greater than a flea, the hardest launch of any animal. Read the guide →
Fish LC Frontosa Cichlid Cyphotilapia frontosa The frontosa cichlid develops a prominent fatty bump on its forehead as it matures, growing larger and more pronounced with age in one of Lake Tanganyika's largest and longest-lived cichlids. Read the guide →
Invertebrates VU Frosted Elfin Callophrys irus The frosted elfin depends on two host plants growing in the exact early-successional habitat that fire suppression and development have made increasingly rare, driving steep declines across its range. Read the guide →
Birds LC Fuegian Steamer Duck Tachyeres pteneres The Fuegian steamer duck has lost the ability to fly entirely, instead thrashing powerfully across the water's surface with its wings in a motion that resembles a steamship. Read the guide →
Birds LC Fulmar Prion Pachyptila crassirostris The fulmar prion has a stockier, less comb-lined bill than most of its relatives, relying more on catching individual prey items than the bulk filter-feeding typical of other prion species. Read the guide →
Invertebrates NE Funnel-web Spider Atracidae A funnel-web spider is a glossy-black Australian spider with among the most dangerous venom of any spider to humans, though an antivenom introduced in 1981 means no one has died from a bite since. Read the guide →
Reptiles LC Gaboon Viper Bitis gabonica The Gaboon viper has the longest fangs and one of the highest venom yields of any snake, yet it is placid and so well camouflaged in leaf litter that people walk right over it. Read the guide →
Birds LC Galah Eolophus roseicapilla The galah pairs a soft pink chest with pale grey wings, and it is so abundant across Australia that its name has become slang for someone acting foolishly. Read the guide →
Mammals EN Galapagos Fur Seal Arctocephalus galapagoensis The Galapagos fur seal is the smallest of all eared seal species and the only fur seal found year-round in tropical waters, hunting mostly at night to avoid the equatorial heat. Read the guide →
Reptiles VU Galapagos Land Iguana Conolophus subcristatus The Galapagos land iguana survives on volcanic islands by eating cactus pads, spines and all, and lets finches pick ticks off its skin. Introduced predators once wiped it out on several islands. Read the guide →
Birds EN Galapagos Penguin Spheniscus mendiculus The Galapagos penguin is the only penguin species found north of the equator, surviving in the tropics entirely thanks to a cold ocean current flowing through the islands it calls home. Read the guide →
Mammals EN Galapagos Sea Lion Zalophus wollebaeki The Galapagos sea lion is remarkably unafraid of people, often approaching swimmers and lounging directly on boats and benches across the same islands famous for giant tortoises and marine iguanas. Read the guide →
Reptiles VU Galápagos Tortoise Chelonoidis niger The Galápagos tortoise is the largest living tortoise and one of the longest-lived animals, with shell shapes that differ island to island — an observation that helped inspire evolutionary theory. Read the guide →
Birds LC Gambel's Quail Callipepla gambelii Gambel's quail thrives in true desert where most game birds could not survive, drawing much of its water needs directly from the succulent plants and insects it eats. Read the guide →
Mammals LC Gambian Mongoose Mungos gambianus The Gambian mongoose is a close relative of the far better-known banded mongoose, living in social groups across West African savanna and forest edge but studied far less than its striped cousin. Read the guide →
Mammals EN Ganges River Dolphin Platanista gangetica The Ganges river dolphin is functionally blind, having lost the ability to form images, relying on extraordinarily refined echolocation to hunt within the murky, sediment-heavy rivers of South Asia. Read the guide →
Fish NE Gar Lepisosteidae A gar is a long, cylindrical, heavily armoured freshwater fish little changed in 100 million years, breathing air through its swim bladder and ambushing prey with a beak full of needle teeth. Read the guide →
Invertebrates LC Garden Bumblebee Bombus hortorum The garden bumblebee is a long-faced, long-tongued bumblebee with yellow bands and a white tail that feeds from deep tubular flowers such as foxgloves and honeysuckle. Read the guide →
Mammals NT Garden Dormouse Eliomys quercinus The garden dormouse wears a distinctive black mask across its eyes and has mysteriously vanished from huge parts of its former range for reasons still unclear. Read the guide →
Fish LC Garden Eel Heteroconger A garden eel lives mostly buried in a sandy burrow, poking its head out to sway and feed on drifting plankton, and colonies of hundreds swaying together look like an underwater field of grass. Read the guide →
Amphibians LC Garden Slender Salamander Batrachoseps major The garden slender salamander thrives under flowerpots and mulch in ordinary Southern California yards, waiting out the dry summer underground for the first cool, wet nights of autumn. Read the guide →
Invertebrates LC Garden Snail Cornu aspersum The garden snail is the common brown-shelled snail of European gardens and hedgerows, a hermaphrodite that fires a chalky love dart at its mate and seals itself in to wait out dry spells. Read the guide →
Invertebrates LC Garden Spider Argiope aurantia The garden spider weaves a thick, zigzagging band of silk through the center of its web, a structure so conspicuous that researchers still debate exactly what purpose it actually serves. Read the guide →
Invertebrates NE Garden Tiger Moth Arctia caja The garden tiger moth is a bold brown-and-cream moth with warning-red hindwings and a very hairy woolly bear caterpillar, once a common garden visitor and now sharply reduced across Britain. Read the guide →
Amphibians VU Gardiner's Seychelles Frog Sechellophryne gardineri Gardiner's Seychelles frog is one of the smallest frogs on Earth, an adult fitting on a fingernail. It has no eardrum, yet still hears, apparently routing sound through its mouth cavity. Read the guide →
Reptiles VU Gargoyle Gecko Rhacodactylus auriculatus The gargoyle gecko is a New Caledonian lizard named for bumpy, horn-like head projections, and it has become a popular pet gecko thanks to easy captive breeding and countless colour forms. Read the guide →
Fish LC Garibaldi Hypsypops rubicundus The garibaldi is a brilliant orange damselfish and California's official state marine fish, whose males tend a private patch of red algae to attract a mate and guard her eggs. Read the guide →
Reptiles NE Garter Snake Thamnophis A garter snake is a small, striped, mild-mannered North American snake, the continent's most widespread, that survives being eaten by toxic newts and gathers by the thousand in winter dens. Read the guide →
Amphibians EX Gastric-brooding Frog Rheobatrachus silus The gastric-brooding frog swallowed its own eggs, shut down its stomach, and grew its young inside it — then brought up fully formed froglets. Both species vanished within a decade of discovery. Read the guide →
Invertebrates LC Gatekeeper Pyronia tithonus The gatekeeper, or hedge brown, is an orange-and-brown butterfly of hedgerows and field edges in July and August, with a twin-pupilled eyespot and a love of bramble flowers. Read the guide →
Reptiles NE Gecko Gekkota A gecko is a small lizard that can run up glass and hang from a ceiling on toe pads gripped by millions of microscopic hairs, and it is the only lizard group that chirps, clicks, and barks. Read the guide →
Mammals LC Gelada Theropithecus gelada The gelada is the only primate that survives mainly by grazing on grass, living in some of the largest social herds of any primate across Ethiopia's highlands. Read the guide →
Mammals LC Gemsbok Oryx gazella The gemsbok can survive for extended periods without drinking water, extracting most of its moisture from plants while a specialised cooling system keeps its brain safe from the worst desert heat. Read the guide →
Mammals LC Genet Genetta A genet is a slender, spotted, long-tailed African carnivore related to the civet, once kept semi-tame in Europe for rodent control centuries before the domestic cat took over that role. Read the guide →
Birds LC Gentoo Penguin Pygoscelis papua The gentoo penguin is the fastest bird in the water, hitting 36 km/h underwater, and it courts its mate with a gift of pebbles. Learn how gentoos live at the edge of Antarctica. Read the guide →
Invertebrates LC Geoduck Panopea generosa The geoduck is the largest burrowing clam in the world, with a siphon so long it can never fully retract into its shell, and individuals have been documented living well over a century. Read the guide →
Mammals LC Geoffroy's Cat Leopardus geoffroyi Geoffroy's cat is one of the most abundant small wild cat species in southern South America, adapting readily to habitats ranging from Patagonian steppe to dense scrubland. Read the guide →
Reptiles CR Geometric Tortoise Psammobates geometricus The geometric tortoise is a tiny South African tortoise with a star-patterned shell, found only in a few fragments of Western Cape lowland shrubland, and one of the rarest tortoises in the world. Read the guide →
Amphibians VU Georgetown Salamander Eurycea naufragia The Georgetown salamander survives only in a handful of springs and caves near one Texas city, dependent on groundwater the city's own growth increasingly threatens. Read the guide →
Amphibians VU Georgia Blind Salamander Haideotriton wallacei The Georgia blind salamander lives its entire life in the total darkness of underground limestone aquifers, having lost both eyes and all body pigment, keeping its feathery external gills for life. Read the guide →
Mammals NT Gerenuk Litocranius walleri The gerenuk is a long-necked antelope of East Africa's dry bush that stands on its hind legs to browse leaves other antelopes cannot reach. It rarely if ever needs to drink water. Read the guide →
Mammals LC Gervais' Beaked Whale Mesoplodon europaeus Gervais' beaked whale is known almost entirely from strandings rather than live sightings, one of the more obscure members of a poorly understood family found across the warmer Atlantic Ocean. Read the guide →
Reptiles CR Gharial Gavialis gangeticus The gharial is a Critically Endangered Indian river crocodilian with a long thin snout built only for catching fish. Fewer than 1,000 breeding adults remain in a handful of rivers. Read the guide →
Mammals VU Ghost Bat Macroderma gigas The ghost bat is Australia's only carnivorous bat, a pale, large-eared predator that ambushes birds, reptiles, and even other bats from a still perch overhead. Read the guide →
Invertebrates LC Ghost Crab Ocypode The ghost crab is a pale, lightning-fast beach runner that can outsprint a jogging human, yet still has to dash back to the surf every so often just to keep its own gills wet enough to breathe. Read the guide →
Invertebrates NE Ghost Mantis Phyllocrania paradoxa The ghost mantis grows leaf-shaped flaps across its body that make it nearly indistinguishable from a dead, curling leaf, an ambush predator that survives by looking inedible. Read the guide →
Invertebrates LC Giant African Land Snail Lissachatina fulica The giant African land snail grows to the size of an adult's hand, lays 1,200 eggs a year, eats 500-plus kinds of plant, and carries a parasite that can cause meningitis. Read the guide →
Invertebrates NE Giant African Millipede Archispirostreptus gigas The giant African millipede is the world's largest millipede, up to 38 cm with 300 to 400 legs. It is a slow, harmless decomposer that curls into a spiral and oozes a defensive fluid when alarmed. Read the guide →
Invertebrates LC Giant Amphipod Alicella gigantea The giant amphipod can grow over thirty times larger than its shallow-water relatives, a scavenger of the deepest ocean trenches that shows just how extreme size can become in the abyss. Read the guide →
Mammals VU Giant Anteater Myrmecophaga tridactyla The giant anteater has no teeth, a 60-centimetre tongue that flicks 150 times a minute, and a body temperature lower than almost any other mammal. It eats up to 30,000 ants and termites a day. Read the guide →
Birds VU Giant Antpitta Grallaria gigantea The giant antpitta is one of the rarest and most secretive birds in the Andes, so elusive that even dedicated researchers rarely manage to see one. Read the guide →
Mammals VU Giant Armadillo Priodontes maximus The giant armadillo is the largest living armadillo species, carrying up to 100 teeth, more than almost any other land mammal, and digging burrows large enough for a person to crawl into. Read the guide →
Invertebrates NE Giant Asian Mantis Hierodula membranacea The giant Asian mantis ranks among the largest mantis species kept by enthusiasts, powerful enough to tackle prey considerably larger than itself, including small lizards and frogs. Read the guide →
Invertebrates VU Giant Clam Tridacna gigas The giant clam is the largest bivalve on Earth — over a metre wide and 200 kg — and it farms algae in its own flesh for most of its food. The "man-eating clam" is a myth. Read the guide →
Birds LC Giant Coot Fulica gigantea The giant coot builds nest mounds of piled vegetation so large they can weigh over a tonne, anchored to the floor of high Andean lakes. Read the guide →
Birds LC Giant Coua Coua gigas The giant coua is the largest member of its family, a mostly terrestrial Madagascar bird that walks and runs through the forest floor far more often than it flies. Read the guide →
Fish LC Giant Danio Devario aequipinnatus The giant danio is the largest commonly kept member of the danio group, a fast, torpedo-shaped schooling fish that appreciates far more open swimming space than its smaller relatives. Read the guide →
Mammals LC Giant Eland Taurotragus derbianus The giant eland is taller than its common eland relative, a huge, chestnut-striped antelope of West and Central African woodland whose western population has become critically endangered. Read the guide →
Mammals LC Giant Forest Hog Hylochoerus meinertzhageni The giant forest hog is the largest wild pig in the world, a black-haired, grass-eating forest animal of equatorial Africa with large pads of skin beneath its eyes. Read the guide →
Fish EN Giant Freshwater Stingray Urogymnus polylepis The giant freshwater stingray is one of the largest freshwater fish on Earth, its disc up to 2.2 m across. A 300 kg ray caught in the Mekong in 2022 set a world record. Its tail spine can pierce bone. Read the guide →
Reptiles VU Giant Garter Snake Thamnophis gigas The giant garter snake has lost most of its original California wetland habitat to agriculture, now surviving largely in irrigation canals and rice fields rather than the marshes it once depended on. Read the guide →
Invertebrates VU Giant Gippsland Earthworm Megascolides australis The giant Gippsland earthworm of southeastern Australia stretches to a metre relaxed and nearly three when pulled, living metres deep in wet clay. Its burrowing makes a gurgle heard from the surface. Read the guide →
Mammals EN Giant Golden-Crowned Flying Fox Acerodon jubatus The giant golden-crowned flying fox is one of the heaviest bats on Earth, a Philippine endemic named for the golden fur crowning its head, now Endangered from hunting. Read the guide →
Fish LC Giant Gourami Osphronemus goramy The giant gourami grows up to 70 centimetres, far larger than its small, popular aquarium relatives, and serves as a major farmed food fish across Southeast Asia. Read the guide →
Fish DD Giant Grouper Epinephelus lanceolatus The giant grouper is the largest bony fish on coral reefs — up to 2.7 m and 400 kg — and it feeds by opening its cavernous mouth to inhale prey whole, including small sharks and lobsters. Read the guide →
Fish CR Giant Guitarfish Glaucostegus typus The giant guitarfish is a ray shaped like a shark with a flattened, pointed head — a shy, shallow-water bottom feeder now Critically Endangered because its fins are prized for shark-fin soup. Read the guide →
Invertebrates NE Giant House Spider Eratigena atrica The giant house spider is a large, long-legged brown spider that weaves funnel-shaped webs in sheds and outbuildings, and whose wandering males are the ones found stranded in baths each autumn. Read the guide →
Birds LC Giant Hummingbird Patagona gigas The giant hummingbird is the largest hummingbird species in the world, so much bigger than its relatives that its wingbeats are visible to the naked eye rather than blurring into a hum. Read the guide →
Invertebrates NE Giant Huntsman Spider Heteropoda maxima The giant huntsman has the largest leg span of any spider — up to 30 cm — and lives in the caves of Laos. Huntsman spiders run sideways at speed and build no web. Read the guide →
Invertebrates NE Giant Ichneumon Wasp Megarhyssa macrurus The female giant ichneumon wasp carries an ovipositor longer than her own body, drilling it through solid wood to reach a hidden wood-wasp larva deep inside a tree. Read the guide →
Invertebrates NE Giant Isopod Bathynomus giganteus The giant isopod is a deep-sea relative of the woodlouse the size of a house cat. It scavenges carcasses on the ocean floor and can go years between meals — one captive animal fasted over five. Read the guide →
Mammals EN Giant Jumping Rat Hypogeomys antimena The giant jumping rat is a rabbit-sized Madagascar rodent that hops on long hind legs like a small kangaroo and digs an elaborate multi-chamber burrow system. Read the guide →
Mammals EN Giant Kangaroo Rat Dipodomys ingens The giant kangaroo rat is the largest of its kind, an Endangered seed-eater of central California whose burrows and seed stores shape the grassland around them. Read the guide →
Birds LC Giant Kingfisher Megaceryle maxima The giant kingfisher is the largest kingfisher found anywhere in Africa, a powerful hunter capable of taking prey well beyond the small fish that make up most kingfishers' diets. Read the guide →
Invertebrates LC Giant Larvacean Bathochordaeus The giant larvacean builds a mucus filtering house nearly a metre across, then abandons the clogged structure and builds an entirely new one several times a day. Read the guide →
Reptiles LC Giant Leaf-tailed Gecko Uroplatus fimbriatus The giant leaf-tailed gecko is the largest member of its genus, using fringed skin flaps along its body to erase any visible shadow or outline against tree bark. Read the guide →
Invertebrates LC Giant Leopard Moth Hypercompe scribonia The giant leopard moth reveals a hidden defence when disturbed, curling into a ball and exposing bright red-orange bands on its abdomen while releasing a drop of foul-tasting fluid to deter predators. Read the guide →
Mammals LC Giant Mexican Shrew Megasorex gigas The giant Mexican shrew is the largest shrew species found anywhere in the New World, though even at its record-holding size it would still fit comfortably in the palm of a hand. Read the guide →
Fish LC Giant Moray Gymnothorax javanicus The giant moray is the largest-bodied moray eel, an Indo-Pacific reef ambush hunter that also teams up with groupers on cooperative hunts, a rare case of two predator species working together. Read the guide →
Fish LC Giant Oarfish Regalecus glesne The giant oarfish is the longest bony fish in the world — a silver ribbon up to 8 metres long that lives in the deep open ocean, swims vertically, and inspired sea-serpent legends. Read the guide →
Mammals EN Giant Otter Pteronura brasiliensis The giant otter is the longest member of the weasel family — up to 1.8 m — and the most social otter, living in loud, tight family groups that hunt fish together and mob caimans off their turf. Read the guide →
Invertebrates NE Giant Owl Butterfly Caligo memnon The giant owl butterfly carries huge owl-like eyespots on its underwings, flies at dusk, and feeds on rotting fruit, and its caterpillars can be a pest in banana plantations. Read the guide →
Invertebrates LC Giant Pacific Octopus Enteroctopus dofleini The giant Pacific octopus is the largest octopus in the world — up to 9 m across — with 2,000 suckers that taste what they touch and a boneless body that can squeeze through a lemon-sized hole. Read the guide →
Amphibians NT Giant Palm Salamander Bolitoglossa dofleini The giant palm salamander of Central America is one of the largest lungless salamanders. It climbs wet leaves on suction-cup feet and fires its tongue faster than almost any vertebrate movement. Read the guide →
Mammals VU Giant Panda Ailuropoda melanoleuca The giant panda is a bear that eats almost nothing but bamboo. Learn how it survives on a low-energy diet, why cubs are so tiny, and how it went from Endangered to Vulnerable. Read the guide →
Mammals EN Giant Pangolin Smutsia gigantea The giant pangolin is the largest of all pangolin species, digging extensive burrows and tearing open termite mounds with powerful claws rather than climbing trees like its smaller relatives. Read the guide →
Amphibians CR Giant Salamander Cryptobranchidae A giant salamander is the largest amphibian alive, a wrinkled, flat-headed river dweller that breathes mostly through folds of loose skin and can pass a century in the same cold stream. Read the guide →
Reptiles LC Giant Spotted Whiptail Aspidoscelis stictogramma One of the largest whiptail lizards in the United States, the giant spotted whiptail is a fast hunter of rocky desert canyons that digs through leaf litter with real determination. Read the guide →
Invertebrates LC Giant Squid Architeuthis dux The giant squid is a deep-sea predator up to 12–13 metres long with eyes the size of dinner plates. It was never filmed alive until 2012, and much of its life remains unknown. Read the guide →
Invertebrates LC Giant Swallowtail Papilio cresphontes The giant swallowtail is the largest butterfly in North America, its caterpillar disguised as bird droppings and armed with a foul-smelling gland, earning the nickname orange dog among growers. Read the guide →
Fish LC Giant Trevally Caranx ignobilis The giant trevally is the apex predator of many Indo-Pacific reefs, up to 1.7 m and 80 kg. In one Seychelles atoll it leaps from the shallows to snatch fledgling terns out of the air. Read the guide →
Invertebrates NE Giant Triton Charonia tritonis The giant triton is one of the largest sea snails and one of few animals that eats the coral-killing crown-of-thorns starfish; its shell has been blown as a trumpet for thousands of years. Read the guide →
Invertebrates NE Giant Tube Worm Riftia pachyptila The giant tube worm lives around deep-sea hydrothermal vents with no mouth, gut, or anus. It feeds through billions of bacteria in its body that turn volcanic hydrogen sulfide into food. Read the guide →
Invertebrates NE Giant Water Bug Lethocerus The giant water bug is a hand-sized aquatic insect that ambushes fish, frogs, and even snakes, injecting a digestive venom and drinking them dry. Its bite is among the most painful of any insect. Read the guide →
Invertebrates VU Giant Weta Deinacrida The giant weta is among the heaviest insects on Earth, one female recorded at 71 grams, heavier than a sparrow. These flightless New Zealand giants fill the niche that mice take elsewhere. Read the guide →
Invertebrates NE Giant Woodwasp Urocerus gigas The giant woodwasp is a large, hornet-like but harmless sawfly with a long egg-laying tube whose larvae tunnel for years through conifer wood with the help of a fungus carried by the mother. Read the guide →
Mammals EN Gibbon Hylobatidae A gibbon is a small tree ape of Southeast Asian rainforest that swings through the canopy faster than any other primate, lives in a monogamous pair, and sings loud duets at dawn. Read the guide →
Reptiles NT Gila Monster Heloderma suspectum The Gila monster is one of only a handful of venomous lizards — a slow, beaded, black-and-orange desert reptile that spends 95% of its life underground and inspired a widely used diabetes drug. Read the guide →
Reptiles LC Gila Spotted Whiptail Aspidoscelis flagellicaudus The Gila spotted whiptail forages with quick, jerky movements across rocky canyon slopes, constantly flicking its tongue to track insect scent trails other lizards would simply overlook. Read the guide →
Birds LC Gila Woodpecker Melanerpes uropygialis The Gila woodpecker excavates nest cavities directly into towering saguaro cacti, and the hardened, healed chambers it leaves behind later shelter elf owls and other desert species. Read the guide →
Mammals CR Gilbert's Potoroo Potorous gilbertii Gilbert's potoroo was presumed extinct for over a century before its rediscovery in 1994, and remains one of the rarest and most endangered mammals on Earth. Read the guide →
Fish VU Gilt Darter Percina evides The gilt darter has vanished from large parts of its range as dams and sediment transformed the fast, clean riffles it needs, though scattered strongholds remain. Read the guide →
Fish LC Gilthead Seabream Sparus aurata The gilthead seabream is a silvery, gold-browed sea bream of Mediterranean and Atlantic shores that crushes shellfish with powerful teeth, changes sex from male to female, and is widely farmed. Read the guide →
Mammals VU Giraffe Giraffa camelopardalis The giraffe is the tallest animal on Earth, with a heart built to pump blood two metres straight up. Learn how its neck, tongue, and blood pressure work — and why it faces a "silent extinction". Read the guide →
Invertebrates NE Giraffe Weevil Trachelophorus giraffa The giraffe weevil of Madagascar has a neck several times longer in the male than the female, which he uses to fight rivals while she folds a leaf into a tube around each single egg. Read the guide →
Reptiles LC Girdled Lizard Cordylidae Girdled lizards are a southern African family of armoured, ring-scaled lizards including species that roll into a spiky ball, live in social rock-crevice colonies, or bear huge defensive spines. Read the guide →
Fish LC Gizzard Shad Dorosoma cepedianum The gizzard shad filters plankton using a muscular, grinding gizzard-like stomach unusual among fish, an abundant forage species whose sheer numbers quietly support the predatory fish above it. Read the guide →
Fish LC Glass Catfish Kryptopterus vitreus The glass catfish is a small Southeast Asian fish so transparent you can see its spine and internal organs through its skin. Schools of them can flash iridescent colours as they hover in the current. Read the guide →
Amphibians LC Glass Frog Hyalinobatrachium fleischmanni The glass frog has translucent belly skin that shows its beating heart and gut, and it hides its own blood in its liver to become see-through while it sleeps. Learn how and why. Read the guide →
Reptiles LC Glass Lizard Ophisaurus The glass lizard looks exactly like a snake but is a lizard that lost its legs, keeping eyelids and ear openings a snake never has. Its tail shatters into pieces when grabbed. Read the guide →
Invertebrates LC Glass Octopus Vitreledonella richardi The glass octopus is almost entirely see-through, with only its eyes, optic nerve, and digestive tract visible, drifting through open water rather than crawling on the seafloor. Read the guide →
Invertebrates VU Glass Sponge Hexactinellida The glass sponge builds its entire skeleton from silica spun into glass-like spicules, some individuals estimated to be over ten thousand years old, forming vast reef structures on the deep seafloor. Read the guide →
Invertebrates LC Glass Squid Cranchiidae The glass squid has a nearly transparent, gelatinous body that hides it almost completely in open water, with only its digestive gland and eyes typically visible against the surrounding sea. Read the guide →
Invertebrates NE Glasswing Butterfly Greta oto The glasswing butterfly has transparent wings that let it blend into the background, and is protected from predators by toxins it collects from plants as a caterpillar and adult. Read the guide →
Birds LC Glaucous Gull Larus hyperboreus The glaucous gull is one of the largest gulls in the Arctic, instantly recognisable for lacking the dark wingtips almost every other large gull species has, leaving its wings pale from tip to tip. Read the guide →
Invertebrates LC Globe Skimmer Pantala flavescens The globe skimmer is the most widespread dragonfly on Earth and the longest-distance insect migrant, crossing the Indian Ocean on the monsoon winds in a relay of generations. Read the guide →
Reptiles LC Glossy Crayfish Snake Regina rigida The glossy crayfish snake stays hidden by day beneath mats of vegetation in southeastern swamps, emerging after dark to hunt for crayfish freshly emerged from their molt. Read the guide →
Birds LC Glossy Ibis Plegadis falcinellus The glossy ibis appears dark and unremarkable from a distance, but breeding adults catch the light in an iridescent sheen of bronze, purple, and green rarely appreciated until seen up close. Read the guide →
Reptiles LC Glossy Snake Arizona elegans The glossy snake carries unusually smooth, shiny scales that give it a distinctive sheen unlike most other desert snakes, a nocturnal constrictor that spends the heat of the day buried in loose sand. Read the guide →
Invertebrates NE Glow-worm Lampyris noctiluca The glow-worm is a beetle, not a worm, whose wingless adult female climbs a grass stem on summer nights and shines a steady green light from her tail to call in the small flying male. Read the guide →
Fish LC Glowlight Danio Danio choprae The glowlight danio carries a coppery-orange stripe that seems to glow along a slim, blue-black body, a relatively recent addition to the aquarium hobby compared with its longer-established relatives. Read the guide →
Birds LC Gnatcatcher Polioptila spp. The gnatcatcher weighs barely more than a coin yet defends its territory with a constantly wagging tail and a thin, wheezy call, one of the smallest, most restless hunters in North American woodlands. Read the guide →
Fish LC Goblin Shark Mitsukurina owstoni The goblin shark is a pink, flabby deep-sea shark with a long flat snout and jaws that shoot forward on cartilage stalks to snatch prey. It is the last of a shark family 125 million years old. Read the guide →
Fish NE Goby Gobiidae A goby is a small bottom-living fish whose pelvic fins are fused into a suction disc, and the family is among the largest of all vertebrate families, with well over 2,000 species. Read the guide →
Mammals VU Goitered Gazelle Gazella subgutturosa The goitered gazelle's males develop a temporary swelling on the throat during the breeding season, an enlarged larynx that gives this Central Asian gazelle its unusual common name. Read the guide →
Reptiles LC Gold Dust Day Gecko Phelsuma laticauda The gold dust day gecko carries flecks of shimmering gold across a green body, a Madagascar lizard so successful outside its range that it now thrives as an introduced species across Hawaii. Read the guide →
Reptiles CR Golden Coin Turtle Cuora trifasciata The golden coin turtle is a small box turtle with three dark stripes on a golden-brown shell, so prized in traditional medicine that it is among the world's most valuable and threatened turtles. Read the guide →
Fish LC Golden Dorado Salminus brasiliensis The golden dorado is a powerful South American river predator nicknamed the river tiger, prized by anglers for its spectacular aerial leaps when hooked. Read the guide →
Birds LC Golden Eagle Aquila chrysaetos The golden eagle is one of the largest and most widespread birds of prey in the Northern Hemisphere, a mountain hunter that stoops on prey at highway speeds. Learn how it lives and hunts. Read the guide →
Invertebrates NE Golden Jewel Beetle Chrysochroa fulgidissima The golden jewel beetle's shimmering iridescent shell has been used for centuries in traditional Japanese decorative art, prized for a colour that never fades even after the insect dies. Read the guide →
Mammals EN Golden Lion Tamarin Leontopithecus rosalia The golden lion tamarin is a fist-sized monkey with a blazing orange mane, found only in a sliver of Brazilian rainforest. Down to about 200 animals in the 1970s, it has rebounded past 4,800. Read the guide →
Amphibians CR Golden Mantella Mantella aurantiaca The golden mantella is a brilliant orange Madagascan frog the size of a coin, toxic from the ants it eats, that breeds only in a handful of swampy forest ponds and is now Critically Endangered. Read the guide →
Invertebrates NE Golden Orb-weaver Spider Trichonephila clavipes The golden orb-weaver spins a wheel-shaped web up to a metre across, strong enough to snare small birds on rare occasions. Females can be over a hundred times heavier than males. Read the guide →
Birds LC Golden Pheasant Chrysolophus pictus The golden pheasant is one of the most extravagantly coloured birds on Earth, with males raising a fan-like golden-orange cape around the face during courtship display. Read the guide →
Amphibians EN Golden Poison Frog Phyllobates terribilis The golden poison frog is the most toxic animal on Earth — one wild frog carries enough batrachotoxin to kill 10 people. Read the guide →
Fish LC Golden Redhorse Moxostoma erythrurum The golden redhorse takes its name from a brassy sheen and reddish fins, one of the more common and adaptable members of a sucker group generally sensitive to poor water. Read the guide →
Fish LC Golden Shiner Notemigonus crysoleucas The golden shiner schools in tight, mixed groups with other small fish, a shimmering, deep-bodied baitfish whose sheer abundance makes it one of the most heavily farmed fish in North America. Read the guide →
Mammals EN Golden Snub-Nosed Monkey Rhinopithecus roxellana The golden snub-nosed monkey lives at higher altitudes than almost any primate besides humans, its nearly bridgeless nose an adaptation against frostbite. Read the guide →
Birds LC Golden Tanager Tangara arthus The golden tanager belongs to Tangara, the most species-rich tanager genus of all, its vivid yellow plumage varying subtly across the Andes. Read the guide →
Amphibians EX Golden Toad Incilius periglenes The golden toad lived in one patch of Costa Rican cloud forest, the males a fluorescent orange. Found in 1966, last seen in 1989 — an early extinction linked to climate change. Read the guide →
Birds LC Golden-collared Manakin Manacus vitellinus The golden-collared manakin snaps its wing feathers together to produce a loud mechanical crack during courtship, performed alongside a moonwalk-like sliding dance. Read the guide →
Mammals CR Golden-Crowned Sifaka Propithecus tattersalli The golden-crowned sifaka wasn't formally described until 1988 and survives today in one of the smallest ranges of any lemur species in northeastern Madagascar. Read the guide →
Birds LC Golden-fronted Woodpecker Melanerpes aurifrons The golden-fronted woodpecker carries a warm patch of yellow-orange across its forehead, a highly adaptable bird found from dense Texan woodland to dry Mexican scrub. Read the guide →
Mammals EN Golden-Headed Lion Tamarin Leontopithecus chrysomelas The golden-headed lion tamarin wears a mane of golden fur around its face and survives today in only a small, fragmented part of Brazil. Read the guide →
Mammals LC Golden-mantled Ground Squirrel Callospermophilus lateralis The golden-mantled ground squirrel looks like an oversized chipmunk with a copper-gold head and shoulders, a bold mountain scrounger that lacks stripes on its face. Read the guide →
Invertebrates LC Golden-ringed Dragonfly Cordulegaster boltonii The golden-ringed dragonfly is a huge black dragonfly with yellow rings and green eyes, whose female stabs her eggs into the mud of upland streams with a long ovipositor. Read the guide →
Mammals EN Golden-Rumped Elephant Shrew Rhynchocyon chrysopygus The golden-rumped elephant shrew flashes a brilliant patch of golden fur across its rear as it sprints down a network of cleared escape trails it maintains daily through Kenyan coastal forest. Read the guide →
Amphibians VU Golden-striped Salamander Chioglossa lusitanica The golden-striped salamander of northwest Iberia is a slim, fast amphibian with a tail twice its body length that it drops when grabbed, and a long tongue it fires to catch flying insects. Read the guide →
Birds NT Golden-Winged Warbler Vermivora chrysoptera The golden-winged warbler has declined so sharply it now regularly hybridizes with the blue-winged warbler, producing the "Brewster's" and "Lawrence's" hybrids birders sometimes mistake for a species. Read the guide →
Invertebrates NE Goldenrod Crab Spider Misumena vatia The goldenrod crab spider is a flower-hunting ambusher that can change colour between white and yellow to match its blossom, and which kills bees and butterflies much larger than itself. Read the guide →
Fish LC Goldfish Carassius auratus The goldfish is a domesticated Asian carp bred for colour for over a thousand years. Freed into the wild it loses its colour, grows to 2 kg, and becomes a destructive invasive fish. Read the guide →
Fish LC Goldstripe Darter Etheostoma parvipinne The goldstripe darter is one of the few darters that thrives in shallow, sluggish, sometimes barely-flowing seeps and spring runs, a habitat most of its fast-water-loving relatives avoid entirely. Read the guide →
Invertebrates NE Goliath Beetle Goliathus goliatus The goliath beetle is among the heaviest insects on Earth — a larva can weigh as much as a small bird. Adults reach 11 cm, fly with a helicopter-like drone, and feed on tree sap and fruit. Read the guide →
Invertebrates NE Goliath Birdeater Theraphosa blondi The goliath birdeater is the heaviest spider in the world, with 2-centimetre fangs and a coat of barbed defensive hairs. Learn what it actually eats, how it hisses, and why it rarely bites people. Read the guide →
Amphibians EN Goliath Frog Conraua goliath The goliath frog is the largest frog on Earth, big enough to move rocks its own body weight to build egg nurseries. Learn how it lives in West African waterfalls and why it is Endangered. Read the guide →
Fish VU Goliath Grouper Epinephelus itajara The Atlantic goliath grouper reaches 2.5 metres and 360 kilograms, one of the largest reef bony fish. It booms a sound felt more than heard, and was fished almost to disappearance before a 1990 ban. Read the guide →
Birds LC Goliath Heron Ardea goliath The goliath heron is the largest living heron in the world, a towering hunter powerful enough to catch and swallow fish that would overwhelm almost any other wading bird. Read the guide →
Fish LC Goliath Tigerfish Hydrocynus goliath The goliath tigerfish is the Congo's largest predator, up to 1.5 m and 50 kg, with 32 dagger teeth that interlock when the jaws shut. It is one of very few freshwater fish reported to bite people. Read the guide →
Mammals EN Goodfellow's Tree Kangaroo Dendrolagus goodfellowi Goodfellow's tree kangaroo spends nearly its entire life in the rainforest canopy, gripping branches with strong curved claws rather than hopping across open ground like its terrestrial relatives. Read the guide →
Birds NE Goose Anserinae A goose is a large grazing waterfowl between the ducks and the swans in size, migrating in V-formations, pairing for many years, and defending its nest and goslings with real aggression. Read the guide →
Invertebrates NE Gooseneck Barnacle Pollicipes pollicipes The gooseneck barnacle is a stalked crustacean that clings to surf-battered rock by a tough black neck, combing plankton from the waves, and is harvested at great risk as the seafood percebes. Read the guide →
Amphibians NT Gopher Frog Lithobates capito The gopher frog of the southeastern US spends most of its life sheltering in the burrow of a gopher tortoise, coming out on rainy winter nights to breed explosively in temporary, fishless ponds. Read the guide →
Reptiles LC Gopher Snake Pituophis catenifer The gopher snake is a big, harmless rodent-eating constrictor of western North America that survives by impersonating a rattlesnake, hissing and buzzing its tail in dry leaves. Read the guide →
Reptiles VU Gopher Tortoise Gopherus polyphemus The gopher tortoise digs long, deep burrows in the sandy pinelands of the southeastern US that shelter more than 350 other species, making it one of North America's most important keystone animals. Read the guide →
Mammals NT Goral Naemorhedus goral The goral bounds confidently across near-vertical rocky cliffs, a small, agile Himalayan goat-antelope closely related to the larger, forest-dwelling serow. Read the guide →
Invertebrates NE Gorgonian Gorgonacea The gorgonian grows into a flat, branching fan shape angled precisely across the current, a soft coral relative that filters plankton with a colony-wide efficiency few reef structures match. Read the guide →
Mammals CR Gorilla Gorilla A gorilla is the largest primate, a mostly plant-eating great ape of central African forest that lives in stable family groups led by a silverback male, and both species are Critically Endangered. Read the guide →
Birds LC Goshawk Accipiter gentilis The goshawk pursues prey through dense forest at full speed, weaving between trunks and branches with a precision that makes it one of the most formidable and agile hunters in the entire hawk family. Read the guide →
Birds VU Gough Moorhen Gallinula comeri The Gough moorhen has lost the ability to fly, evolving on a predator-free island until introduced house mice turned into an unexpected new threat to its eggs and chicks. Read the guide →
Reptiles LC Gould's Monitor Varanus gouldii Gould's monitor, or the sand goanna, is a big, banded Australian lizard that forages widely across dry country, digs deep burrows, and stands on its hind legs to survey its surroundings. Read the guide →
Fish LC Gourami Osphronemidae A gourami is a Southeast Asian labyrinth fish that breathes air at the surface, has thread-like pelvic feelers, and, in most species, the male builds a floating bubble nest and guards the eggs. Read the guide →
Reptiles LC Graham's Crayfish Snake Regina grahamii Graham's crayfish snake feeds almost exclusively on crayfish, timing its hunts around freshly molted, soft-shelled prey it can actually swallow without a struggle. Read the guide →
Reptiles EN Grand Cayman Blue Iguana Cyclura lewisi The Grand Cayman blue iguana is a turquoise lizard that fell to perhaps 15 wild animals before a captive-breeding programme pulled it back to over a thousand. It can live nearly 70 years. Read the guide →
Reptiles LC Granite Spiny Lizard Sceloporus orcutti The granite spiny lizard's males flash a brilliant iridescent blue-purple sheen while basking on the very rocks that give the species its name. Read the guide →
Mammals LC Grant's Gazelle Nanger granti Grant's gazelle can go without drinking water for extended periods, a larger, paler relative of Thomson's gazelle often mistaken for its more famous cousin. Read the guide →
Fish LC Grass Carp Ctenopharyngodon idella The grass carp can eat close to its own body weight in aquatic plants each day, a hunger deliberately put to work controlling weeds in lakes and canals worldwide. Read the guide →
Reptiles LC Grass Snake Natrix natrix The grass snake is the largest and commonest snake in Britain, a harmless olive-green swimmer that hunts frogs and toads, lays eggs in compost heaps, and plays dead when threatened. Read the guide →
Invertebrates NE Grasshopper Caelifera Grasshoppers are jumping, plant-eating insects with short antennae and huge hind legs that can fling them twenty body lengths, and a few of them turn into swarming locusts when crowded. Read the guide →
Birds LC Grasshopper Sparrow Ammodramus savannarum The grasshopper sparrow produces an insect-like buzzing trill so similar to an actual grasshopper's call that many people walk right past one without ever realizing a bird made the sound. Read the guide →
Mammals LC Gray Fox Urocyon cinereoargenteus The gray fox is one of the only canids in the world capable of climbing trees, using hooked claws and a rotating wrist to escape predators and reach fruit far above the ground. Read the guide →
Invertebrates LC Gray Hairstreak Strymon melinus The gray hairstreak wears a fake head on the back of its wings, complete with false antennae, a decoy convincing enough that predators often attack the wrong end and let it escape. Read the guide →
Mammals LC Gray Mouse Lemur Microcebus murinus The gray mouse lemur is one of the smallest primates alive and can slip into a low-energy torpor whenever food becomes scarce in its Madagascan forest. Read the guide →
Mammals LC Gray Seal Halichoerus grypus The gray seal is distinguished from other North Atlantic seals by its long, horse-like snout, a large species whose growing US population has drawn white sharks closer to shore. Read the guide →
Amphibians LC Gray Tree Frog Hyla versicolor A gray tree frog is a small, warty North American tree frog that shifts between grey and green, winters frozen almost solid, and hides two identical species told apart only by their trill. Read the guide →
Amphibians LC Gray Treefrog Hyla versicolor The gray treefrog of eastern North America can shift between grey, green, and brown to match bark or leaves, survives its body partly freezing solid each winter, and carries four sets of chromosomes. Read the guide →
Mammals LC Gray Whale Eschrichtius robustus The gray whale undertakes one of the longest migrations of any mammal, travelling thousands of miles between Arctic waters and warm coastal lagoons, feeding by scooping sediment off the ocean floor. Read the guide →
Mammals LC Gray Wolf Canis lupus The gray wolf is a cooperative pack hunter and the wild ancestor of every domestic dog. Learn how packs work, why wolves howl, and how they reshape whole ecosystems. Read the guide →
Mammals VU Gray-Headed Flying Fox Pteropus poliocephalus The gray-headed flying fox is Australia's largest bat, a keystone forest pollinator whose colonies can suffer mass die-offs when temperatures spike past 42 degrees Celsius. Read the guide →
Mammals DD Gray's Beaked Whale Mesoplodon grayi Gray's beaked whale is one of the more frequently stranded beaked whale species in the Southern Hemisphere, though it remains rarely observed alive at sea in its deep, offshore habitat. Read the guide →
Fish LC Grayling Thymallus thymallus The grayling is a silver, thyme-scented river fish with an enormous sail-like fin, a member of the salmon family that lives only in cold, clean, fast water and is prized by winter fly-anglers. Read the guide →
Birds LC Great Antshrike Taraba major The great antshrike announces itself with a deep, rolling growl rather than a typical birdsong, a sound low enough to seem almost mammalian. Read the guide →
Birds VU Great Argus Argusianus argus The male great argus has the longest wing feathers of any wild bird, each covered in golden 'eyes' shaded to look 3D. He throws them into two vast fans around the female, hiding his body. Read the guide →
Birds EX Great Auk Pinguinus impennis The great auk was a flightless North Atlantic seabird, the bird sailors first called a penguin, hunted for its feathers, meat, and eggs until the last pair was killed in Iceland in 1844. Read the guide →
Birds LC Great Barbet Psilopogon virens The great barbet is one of the largest barbets in Asia, a blue-headed bird whose loud, repetitive call rings out across Himalayan foothill forest for hours at a stretch. Read the guide →
Fish LC Great Barracuda Sphyraena barracuda The great barracuda is a torpedo-shaped reef predator with fang-like teeth that strikes at up to 40 km/h. It is curious about swimmers but rarely bites, and its flesh can carry ciguatera poisoning. Read the guide →
Reptiles LC Great Basin Collared Lizard Crotaphytus bicinctores The Great Basin collared lizard can sprint upright on its hind legs alone, a big-headed desert predator well adapted to the rocky terrain of its namesake region. Read the guide →
Amphibians LC Great Basin Spadefoot Spea intermontana The Great Basin spadefoot survives some of the coldest, driest terrain any spadefoot tolerates, buried deep enough underground to avoid winter freezes across the high desert basins of the West. Read the guide →
Birds LC Great Black-backed Gull Larus marinus The great black-backed gull is the largest gull in the world, a powerful predator capable of killing and eating other seabirds, rabbits, and even ducklings whole. Read the guide →
Birds LC Great Blue Heron Ardea herodias The great blue heron is North America's largest heron, an ambush hunter that stands motionless in the shallows for minutes, then spears a fish with a lightning strike of its dagger bill. Read the guide →
Birds VU Great Bustard Otis tarda The great bustard is one of the heaviest flying birds in the world, a bird of open plains where displaying males turn themselves almost inside out into a ball of white feathers. Read the guide →
Birds LC Great Crested Flycatcher Myiarchus crinitus The great crested flycatcher nests inside tree cavities and famously weaves a shed snake skin into the lining, or a strip of plastic when no snake skin is available. Read the guide →
Birds LC Great Crested Grebe Podiceps cristatus The great crested grebe is a slender diving waterbird of open lakes, known for its head plumes, its elaborate courtship dances, and its striped chicks that ride on a parent's back. Read the guide →
Amphibians LC Great Crested Newt Triturus cristatus A great crested newt is a large, warty European newt whose breeding male grows a spectacular jagged crest, and it is protected so strictly that its presence can halt building projects. Read the guide →
Amphibians LC Great Crested Newt Triturus cristatus The great crested newt is Europe's largest newt — a black, warty amphibian with an orange belly whose breeding males grow a jagged dragon-like crest. It is strictly protected across the EU and UK. Read the guide →
Invertebrates LC Great Diving Beetle Dytiscus marginalis The great diving beetle is one of the fiercest hunters in a European pond, an air-carrying underwater predator of tadpoles and small fish whose larva, the water tiger, sucks its prey dry. Read the guide →
Birds LC Great Dusky Swift Cypseloides senex The great dusky swift flies directly through the falling curtain of a waterfall to reach nests hidden behind the water, one of the most extreme nesting strategies of any bird. Read the guide →
Birds LC Great Egret Ardea alba The great egret was hunted to the brink in the late 1800s for its ornamental breeding plumes, a slaughter so severe it helped spark the modern bird conservation movement. Read the guide →
Mammals LC Great Fruit-eating Bat Artibeus lituratus The great fruit-eating bat is a large Neotropical leaf-nosed bat that feeds on figs and other fruit, spreads seeds, and has adapted well to parks and cities. Read the guide →
Mammals LC Great Gerbil Rhombomys opimus The great gerbil builds large colonies of burrows marked by mounds of earth across Central Asia's deserts, and is a natural reservoir of plague. Read the guide →
Birds LC Great Grebe Podiceps major The great grebe is the largest grebe species in South America, an elegant diving waterbird capable of both freshwater lake and sheltered coastal marine habitat. Read the guide →
Invertebrates NE Great Green Bush-cricket Tettigonia viridissima The great green bush-cricket is a large, bright green insect with very long antennae whose males sing a loud, continuous trill at dusk, and whose females have a sword-like egg-laying tube. Read the guide →
Birds LC Great Grey Owl Strix nebulosa The great grey owl looks like the largest owl in the world but is mostly feathers. It hears voles under half a metre of snow and plunges feet-first through the crust to seize them. Read the guide →
Fish CR Great Hammerhead Shark Sphyrna mokarran The great hammerhead is the largest hammerhead shark, using its wing-shaped head to detect and pin stingrays on the seabed. Once common, it is now Critically Endangered from the fin trade. Read the guide →
Birds VU Great Hornbill Buceros bicornis The great hornbill is a metre-long forest bird with a huge yellow bill and casque, wingbeats you can hear from far off, and a nesting habit in which the female seals herself into a tree hole. Read the guide →
Birds LC Great Horned Owl Bubo virginianus The great horned owl is North America's most widespread owl and its fiercest — a powerful nocturnal hunter with a crushing grip, silent flight, and a taste for skunks and other owls. Read the guide →
Mammals LC Great Jerboa Allactaga major The great jerboa can leap several metres in a single bound on its long hind legs, evading predators across the open steppe using speed rather than size. Read the guide →
Amphibians LC Great Plains Narrowmouth Toad Gastrophryne olivacea The Great Plains narrowmouth toad has a tiny pointed head built almost entirely for eating ants and termites, and some individuals live commensally inside tarantula burrows. Read the guide →
Reptiles LC Great Plains Ratsnake Pantherophis emoryi The Great Plains ratsnake was once treated as a subspecies of the corn snake before genetic and physical differences were judged significant enough to recognise it as a fully distinct species. Read the guide →
Reptiles LC Great Plains Skink Plestiodon obsoletus The Great Plains skink hatches with a vivid blue tail that fades as it matures, a large, smooth-scaled lizard that spends much of its life hidden beneath rocks and soil across the central grasslands. Read the guide →
Amphibians LC Great Plains Toad Anaxyrus cognatus The Great Plains toad is a blotchy grey toad of the North American prairies whose male gives one of the longest calls of any amphibian, a jackhammer trill that can run for nearly a minute. Read the guide →
Invertebrates LC Great Pond Snail Lymnaea stagnalis The great pond snail is a large, air-breathing freshwater snail of European and northern ponds that glides upside down along the water surface and is a model animal for studying memory. Read the guide →
Birds LC Great Potoo Nyctibius grandis The great potoo is a large nocturnal bird of American forests that spends the day frozen upright on a broken branch, eyes shut to slits, indistinguishable from the stump it sits on. Read the guide →
Invertebrates LC Great Purple Hairstreak Atlides halesus The great purple hairstreak displays some of the most vividly iridescent blue-green wings of any North American butterfly, a colour visible only when the wings catch light at the right angle. Read the guide →
Invertebrates NE Great Silver Water Beetle Hydrophilus piceus The great silver water beetle is a glossy black giant among European water beetles that carries a silvery film of air, grazes water plants as an adult, and floats its eggs in a silk case with a mast. Read the guide →
Birds LC Great Skua Stercorarius skua The great skua is a heavy brown North Atlantic seabird that lives by piracy, chasing gannets and gulls until they drop their catch, and dive-bombing anyone who comes near its nest. Read the guide →
Birds VU Great Slaty Woodpecker Mulleripicus pulverulentus The great slaty woodpecker is one of the largest woodpeckers alive today, an unusually social bird that moves through Southeast Asian forest in small, noisy family groups. Read the guide →
Invertebrates LC Great Spangled Fritillary Speyeria cybele The great spangled fritillary's caterpillar hatches in autumn, eats nothing at all, and simply waits through winter before finally seeking out the violets it depends on the following spring. Read the guide →
Birds LC Great Spotted Woodpecker Dendrocopos major The great spotted woodpecker is the most common and widespread woodpecker across Europe, drumming rapidly on tree trunks not just to feed but to communicate territory and attract a mate. Read the guide →
Birds LC Great Tit Parus major The great tit is the largest tit in Europe, a bold black-capped, yellow-breasted woodland and garden bird with a huge vocabulary and a black chest stripe that signals how dominant each bird is. Read the guide →
Birds LC Great White Pelican Pelecanus onocrotalus The great white pelican has one of the largest wingspans of any flying bird and a throat pouch that holds more than its stomach. Groups sometimes hunt cooperatively, herding fish together. Read the guide →
Fish VU Great White Shark Carcharodon carcharias The great white is the largest predatory fish alive. Learn how it senses prey, why it breaches, how slowly it reproduces, and what its Vulnerable status really means. Read the guide →
Birds LC Great-winged Petrel Pterodroma macroptera The great-winged petrel is one of the largest gadfly petrels, with unusually long wings suited to fast, dynamic flight, and is unusual among seabirds for breeding during the winter months. Read the guide →
Mammals CR Greater Bamboo Lemur Prolemur simus The greater bamboo lemur is a Critically Endangered Madagascan lemur that eats giant bamboo containing enough cyanide to harm other animals, and survives in only a few small forest areas. Read the guide →
Mammals VU Greater Bilby Macrotis lagotis The greater bilby is an Australian marsupial with huge rabbit-like ears and a long pink snout. A prodigious digger, its spiral burrows shelter dozens of other desert species long after it moves on. Read the guide →
Birds LC Greater Bird-of-paradise Paradisaea apoda Greater birds-of-paradise gather at display trees where males shake out cascades of golden plumes and dance for watching females. The scientific name means "legless" — a mistake from trade skins. Read the guide →
Mammals LC Greater Bulldog Bat Noctilio leporinus The greater bulldog bat rakes its oversized clawed feet through the water to gaff fish detected by the ripples they leave, a hunting method unique among bats. Read the guide →
Mammals LC Greater Cane Rat Thryonomys swinderianus The greater cane rat is farmed widely across West Africa for its meat, a large semi-aquatic rodent capable of causing serious damage to sugarcane fields. Read the guide →
Reptiles LC Greater Earless Lizard Cophosaurus texanus The greater earless lizard has no visible ear openings at all, and it sprints across open desert flats fast enough to rank among the quickest lizards for its size in North America. Read the guide →
Mammals LC Greater False Vampire Bat Megaderma lyra The greater false vampire bat is a large Asian carnivorous bat that preys on frogs, birds, and even other bats, and is not a true vampire bat. Read the guide →
Mammals LC Greater Galago Otolemur crassicaudatus The greater galago communicates through loud, child-like screams that give the bushbaby family its common name, leaping between trees with powerful hind legs under cover of darkness. Read the guide →
Mammals EN Greater Glider Petauroides volans The greater glider is Australia's largest gliding marsupial, sailing up to 100 metres between eucalyptus trees on a membrane from elbow to ankle, and eating almost nothing but gum leaves. Read the guide →
Mammals LC Greater Grison Galictis vittata The greater grison hunts in loosely cooperative pairs across Latin American forest and grassland, a bold, low-slung mustelid whose grey-and-black colouring recalls a small badger. Read the guide →
Mammals LC Greater Hedgehog Tenrec Setifer setosus The greater hedgehog tenrec looks almost identical to a true hedgehog, rolling into a spiny ball when threatened, despite the two having evolved the same defense independently. Read the guide →
Birds LC Greater Honeyguide Indicator indicator The greater honeyguide leads people to wild bees' nests, chattering and flying tree to tree, then feeds on the leftover beeswax. It is one of the few wild animals that cooperates with humans. Read the guide →
Mammals LC Greater Horseshoe Bat Rhinolophus ferrumequinum The greater horseshoe bat emits its echolocation calls through an elaborate horseshoe-shaped nose-leaf rather than its mouth, then wraps itself fully in its wings to roost. Read the guide →
Mammals LC Greater Kudu Tragelaphus strepsiceros The greater kudu bull carries spiralled horns that can complete two and a half full twists, a large African antelope capable of clearing fences well over two metres high. Read the guide →
Mammals EN Greater Long-nosed Bat Leptonycteris nivalis The greater long-nosed bat is an Endangered nectar bat that migrates north from Mexico following blooming agaves, pollinating the desert plants that give us tequila and mezcal. Read the guide →
Mammals LC Greater Mouse-eared Bat Myotis myotis The greater mouse-eared bat is one of Europe's largest bats, hunting large ground beetles by listening for their footsteps and roosting in big colonies in attics and caves. Read the guide →
Fish LC Greater Pipefish Syngnathus acus The greater pipefish is a long, thin, armoured relative of the seahorse that sucks up tiny prey through its tube-like snout, and whose male carries the eggs on the underside of his body. Read the guide →
Birds NT Greater Rhea Rhea americana The greater rhea is South America's largest bird — a flightless runner in which the male incubates eggs from a dozen females and raises the chicks alone, charging anything that comes near them. Read the guide →
Birds LC Greater Roadrunner Geococcyx californianus The greater roadrunner is a ground-dwelling desert cuckoo that runs at 30 km/h chasing lizards and rattlesnakes, and kills its prey by beating it against rocks. Read the guide →
Mammals LC Greater Sac-winged Bat Saccopteryx bilineata The greater sac-winged bat is a two-striped tropical bat whose males perfume their territory from scent pouches in their wings, sing to attract females, and whose pups babble like human infants. Read the guide →
Birds NT Greater Sage-grouse Centrocercus urophasianus Each spring, male greater sage-grouse gather on display grounds called leks and inflate two yellow air sacs on their chests, making a swishing pop that carries across the sagebrush. Read the guide →
Mammals LC Greater Short-nosed Fruit Bat Cynopterus sphinx The greater short-nosed fruit bat is a common South and Southeast Asian fruit bat that eats guavas and figs, spreads seeds, and sometimes roosts in tents it makes from leaves. Read the guide →
Amphibians LC Greater Siren Siren lacertina The greater siren is an eel-shaped aquatic salamander with feathery gills, tiny front legs, and no hind legs at all. It keeps larval features for life and can wait out drought in dried mud for years. Read the guide →
Mammals LC Greater Spear-nosed Bat Phyllostomus hastatus The greater spear-nosed bat is a large, omnivorous leaf-nosed bat that lives in harem groups and uses group-specific screech calls to keep its colony together. Read the guide →
Birds LC Grebe Podicipedidae A grebe is a diving waterbird with legs set so far back it swims superbly but cannot walk, and it performs some of the most elaborate courtship dances of any bird, and eats its own feathers. Read the guide →
Reptiles LC Green Anaconda Eunectes murinus The green anaconda is the heaviest snake in the world, a non-venomous constrictor that ambushes prey from the water. Learn how it kills, why females dwarf males, and how it gives birth. Read the guide →
Amphibians VU Green and Golden Bell Frog Litoria aurea The green and golden bell frog was once one of southeastern Australia's commonest frogs before disease and habitat loss collapsed its range. Its best strongholds are now brick pits and quarry ponds. Read the guide →
Reptiles LC Green Anole Anolis carolinensis The green anole is a small southeastern US lizard sold as an American chameleon for its green-to-brown colour change, though it is no chameleon and is being pushed up into the treetops by an invader. Read the guide →
Reptiles LC Green Basilisk Basiliscus plumifrons The green basilisk can sprint across the surface of a pond on its hind legs before it sinks — the trick that earned it the nickname "Jesus Christ lizard." Read the guide →
Invertebrates NE Green Drake Mayfly Ephemera danica The green drake is a large, cream-and-grey European mayfly whose burrowing nymphs live in river silt for one or two years, before adults hatch in a spectacular emergence and live only a day or two. Read the guide →
Amphibians LC Green Frog Lithobates clamitans The green frog is the frog most people meet at the edge of a pond in eastern North America, the one that gives a single low twang like a loose banjo string and dives with a startled squawk. Read the guide →
Birds LC Green Heron Butorides virescens The green heron is a small, stocky heron of the Americas and one of the few birds that uses tools, dropping insects, feathers, or bread onto the water to lure fish within reach. Read the guide →
Birds LC Green Honeycreeper Chlorophanes spiza Male and female green honeycreepers look like different species entirely, one a brilliant turquoise with a black head, the other solid green. Read the guide →
Reptiles LC Green Iguana Iguana iguana The green iguana is a large tree-dwelling lizard of the American tropics — a leaf-eating reptile with a third eye on its head that has become a damaging invasive species in Florida. Read the guide →
Birds LC Green Kingfisher Chloroceryle americana The green kingfisher favours narrow, sheltered streams that its much larger relative the ringed kingfisher tends to avoid, letting the two related hunters share the same rivers. Read the guide →
Reptiles LC Green Mamba Dendroaspis angusticeps The green mamba is a shy, fast-moving, highly venomous snake that spends nearly its entire life in trees, a bright green ambusher that would rather vanish into leaves than confront anything. Read the guide →
Amphibians EN Green Mantella Mantella viridis The green mantella lives in dry, rocky forest in northern Madagascar unlike the rainforest most of its colourful relatives depend on, surviving in noticeably harsher, more seasonal conditions. Read the guide →
Fish LC Green Moray Eel Gymnothorax funebris The green moray is a large Atlantic reef eel that is actually brown — a yellow mucus coat makes it look green. It has a second set of jaws in its throat that lunge forward to grab prey. Read the guide →
Amphibians NT Green Salamander Aneides aeneus The green salamander is the only North American salamander patterned in lichen-green blotches, camouflage for a life in damp crevices in shaded rock. It climbs vertical stone on squared-off toe tips. Read the guide →
Reptiles EN Green Sea Turtle Chelonia mydas The green sea turtle is the only sea turtle that grazes seagrass as an adult, migrates thousands of kilometres, and returns to its birth beach to nest. Learn how it lives and why it's Endangered. Read the guide →
Invertebrates NE Green Shield Bug Palomena prasina The green shield bug is a shield-shaped bug that is bright green in summer and turns bronze-brown in autumn to overwinter, and gives off a foul smell when disturbed. Read the guide →
Fish NT Green Sturgeon Acipenser medirostris The green sturgeon spends most of its adult life in the open ocean, returning only to a few specific rivers to spawn, making it one of the most marine-oriented North American sturgeon species. Read the guide →
Fish LC Green Sunfish Lepomis cyanellus The green sunfish tolerates murky, degraded water better than most of its sunfish relatives, often becoming the dominant panfish in ponds and streams where others cannot persist. Read the guide →
Fish LC Green Terror Andinoacara rivulatus The green terror carries a fearsome name earned by a territorial streak, with mature males developing a pronounced forehead hump and an iridescent green-and-orange sheen across the body. Read the guide →
Amphibians LC Green Toad Bufotes viridis A green toad is a green-and-white toad of Europe and Asia that tolerates heat, drought, and salt better than almost any amphibian, and whose long trill is often mistaken for a cricket or a bird. Read the guide →
Reptiles LC Green Tree Monitor Varanus prasinus The green tree monitor is a slender, bright emerald lizard built for canopy life, gripping branches with curved claws and a prehensile tail. It rarely, if ever, touches the ground. Read the guide →
Reptiles LC Green Tree Python Morelia viridis The green tree python drapes over a branch in a tight coil with its head resting in the middle. Its young hatch bright yellow or red and turn green as they mature. Read the guide →
Amphibians LC Green Treefrog Dryophytes cinereus The green treefrog is the official state amphibian of both Georgia and Louisiana, a bright frog often seen clinging to windows and porch lights at night, drawn by the insects gathering there. Read the guide →
Reptiles LC Green Water Snake Nerodia cyclopion The green water snake is a large, heavy-bodied non-venomous species that basks in numbers along southern swamps and bayous, frequently mistaken for the venomous cottonmouth it shares habitat with. Read the guide →
Invertebrates NE Green Weaver Ant Oecophylla smaragdina The green weaver ant builds elaborate leaf nests by stitching foliage together with living larvae used as silk-producing tools, a cooperative construction method unique among ants. Read the guide →
Birds LC Green Woodpecker Picus viridis The green woodpecker spends much of its time on the ground rather than clinging to tree trunks, probing open grassland for ants with a long, sticky tongue and a loud, laughing call known as a yaffle. Read the guide →
Amphibians LC Green-and-black Poison Frog Dendrobates auratus The green-and-black poison frog is one of the most familiar dart frogs, marbled in metallic green and black. A population introduced to Hawaii in 1932 to fight mosquitoes still thrives there. Read the guide →
Birds LC Green-backed Firecrown Sephanoides sephaniodes The green-backed firecrown is the southernmost breeding hummingbird species in the world, tolerating cold temperate forest conditions far removed from the tropical climate most hummingbirds prefer. Read the guide →
Birds LC Green-Cheeked Conure Pyrrhura molinae The green-cheeked conure is a small, quieter parrot than most of its noisy conure relatives, a trait that has made it one of the most popular pet parrots for keepers in shared living spaces. Read the guide →
Birds LC Green-crowned Brilliant Heliodoxa jacula The green-crowned brilliant is a relatively large hummingbird of Central American and Andean cloud forest, females identified by a distinctive white stripe below the eye. Read the guide →
Birds LC Green-headed Tanager Tangara seledon The green-headed tanager combines a glossy green head with patches of turquoise, black, and golden orange, one of the most vividly coloured birds of Brazil's Atlantic Forest. Read the guide →
Invertebrates NE Greenbottle Blue Tarantula Chromatopelma cyaneopubescens The greenbottle blue tarantula combines metallic blue legs, a green carapace, and an orange abdomen in one of the most colourful combinations found in any tarantula species. Read the guide →
Amphibians LC Greenhouse Frog Eleutherodactylus planirostris A greenhouse frog is a tiny, coin-sized Caribbean frog that lays its eggs in damp soil, skips the tadpole stage entirely, and has spread as a plant-pot stowaway across the warm parts of the world. Read the guide →
Fish VU Greenland Shark Somniosus microcephalus The Greenland shark is the longest-lived vertebrate on Earth — radiocarbon dating puts one female at up to 512 years old. It grows a centimetre a year, swims in slow motion, and its flesh is toxic. Read the guide →
Fish LC Greenside Darter Etheostoma blennioides The greenside darter grazes algae from rocks using an unusually long, flexible snout, a feeding style shared by few other North American stream fish. Read the guide →
Amphibians LC Gregarious Slender Salamander Batrachoseps gregarius The gregarious slender salamander is often found sharing one sheltered spot with several others of its kind, an unusually social habit that gave the species its name among a normally solitary group. Read the guide →
Fish VU Grenadier Macrouridae The grenadier is the most abundant and diverse group of fish on the deep ocean floor, a large-headed scavenger tapering to a long, thin tail that gives the family its "rattail" nickname. Read the guide →
Mammals EN Grevy's Zebra Equus grevyi Grevy's zebra is the largest wild equid, an Endangered zebra of Kenya and Ethiopia with narrow stripes and big rounded ears that can go days between drinks in dry country. Read the guide →
Birds EN Grey Crowned Crane Balearica regulorum The grey crowned crane wears a golden halo of bristle feathers and is one of only two cranes that can roost in trees. It is Uganda's national bird and has fallen about 80% since the 1980s. Read the guide →
Fish LC Grey Gurnard Eutrigla gurnardus The grey gurnard is a bony-headed, grey-spotted bottom fish of European seas that walks over the sea bed on finger-like fin rays, tastes for prey as it goes, and grunts when taken out of the water. Read the guide →
Birds LC Grey Heron Ardea cinerea The grey heron is the Old World counterpart to the great blue heron, a tall, patient hunter that stands motionless at the water's edge before striking with lightning speed. Read the guide →
Birds LC Grey Partridge Perdix perdix The grey partridge has vanished from much of the European farmland it once filled, its steep decline serving as one of the clearest warning signs of how agricultural intensification reshapes wildlife. Read the guide →
Birds NT Grey Petrel Procellaria cinerea The grey petrel breeds in the depths of the Southern Hemisphere winter, an unusual timing among Southern Ocean seabirds that leaves its chicks growing through the coldest, stormiest months. Read the guide →
Mammals NT Grey Rhebok Pelea capreolus The grey rhebok is the only member of its genus, a shy, woolly-coated South African antelope of mountain grassland that bounds away in a stiff, rocking-horse gait when disturbed. Read the guide →
Birds LC Grey-backed Storm-petrel Garrodia nereis The grey-backed storm-petrel has a distinctive pale grey back that contrasts sharply with its dark wings, foraging over calmer coastal waters closer to shore than many of its relatives. Read the guide →
Birds LC Grey-breasted Seedsnipe Thinocorus orbignyianus The grey-breasted seedsnipe looks and acts like a cross between a quail and a sandpiper, though it belongs to the shorebird family despite feeding entirely on plants. Read the guide →
Mammals LC Grey-Cheeked Mangabey Lophocebus albigena The grey-cheeked mangabey announces its presence with a booming whoop-gobble call that carries for a kilometre through the rainforest canopy. Read the guide →
Birds EN Grey-headed Albatross Thalassarche chrysostoma The grey-headed albatross has been tracked circling the entire Southern Ocean around Antarctica in as little as 46 days, one of the fastest documented circumnavigations by any bird. Read the guide →
Birds LC Grey-headed Kingfisher Halcyon leucocephala The grey-headed kingfisher hunts insects and lizards across dry African savanna as often as it hunts fish, a flexible diet that lets it thrive well away from any river or lake. Read the guide →
Birds LC Grey-headed Woodpecker Picus canus The grey-headed woodpecker is a quieter, more subdued relative of the green woodpecker, sharing its taste for ground-dwelling ants but calling far less loudly. Read the guide →
Mammals VU Grizzled Tree Kangaroo Dendrolagus inustus The grizzled tree kangaroo carries a coarse, grizzled grey-brown coat through the lowland rainforests of New Guinea, one of the larger and less agile tree kangaroo species. Read the guide →
Birds LC Groove-billed Ani Crotophaga sulcirostris The groove-billed ani is identified by a series of grooves running along its bill, a social, all-black bird that nests communally alongside its close relative the smooth-billed ani. Read the guide →
Birds LC Groove-billed Toucanet Aulacorhynchus sulcatus The groove-billed toucanet carries a bill marked with fine grooves along its surface, a small green relative of the large toucans found across the forests of northern South America. Read the guide →
Birds LC Grosbeak Pheucticus A grosbeak is a songbird defined by one feature above all else, an oversized, powerful, cone-shaped bill strong enough to crack open seeds and nuts that would defeat almost any smaller-billed bird. Read the guide →
Amphibians LC Grotto Salamander Eurycea spelaea The grotto salamander is the only North American cave salamander whose larvae hatch with working eyes and then lose them as they mature, the eyelids fusing shut for a lightless adult life underground. Read the guide →
Invertebrates LC Ground Mantis Litaneutria minor The ground mantis hunts directly on bare soil rather than in vegetation, a small, fast-moving predator whose mottled coloring makes it nearly invisible against desert dust and gravel. Read the guide →
Mammals VU Ground Pangolin Smutsia temminckii The ground pangolin, or Temminck's pangolin, is a Vulnerable, armoured anteater of southern and eastern African savanna that shelters in burrows dug by other animals. Read the guide →
Reptiles LC Ground Skink Scincella lateralis The ground skink slithers through leaf litter like a tiny snake rather than walking on its small legs, and a transparent window in its lower eyelid lets it see with eyes shut. Read the guide →
Reptiles LC Ground Snake Sonora semiannulata The ground snake varies so wildly in color across its range that plain gray individuals and boldly banded red-and-black ones can belong to the exact same species. Read the guide →
Birds VU Ground-Roller Brachypteraciidae The ground-roller lives almost entirely on the forest floor, a Madagascar endemic that shares an order with the aerial tumbling rollers of Africa and Asia yet never leaves the ground to display. Read the guide →
Mammals LC Groundhog Marmota monax The groundhog digs an extensive burrow with multiple entrances and dedicated chambers, then spends the winter in genuine deep hibernation, slowing its heart rate until warmer weather returns. Read the guide →
Fish VU Grouper Epinephelinae A grouper is a large, heavy-bodied ambush predator of reefs and rocky bottoms that swallows prey whole with a sudden gulp, can live for decades, and in many species changes sex from female to male. Read the guide →
Birds NE Grouse Tetraoninae A grouse is a plump ground bird of the cold north, feathered to the toes, that lives out winter on conifer needles and buds, and whose males gather to display at traditional arenas called leks. Read the guide →
Fish NE Grunion Leuresthes tenuis The California grunion spawns by riding a wave completely out of the water onto the beach, where females twist tail-first into wet sand to lay eggs before both flip back into the next wave. Read the guide →
Fish LC Grunt Haemulidae A grunt is a reef fish named for the audible grunting sound it produces by grinding its own pharyngeal teeth, a noise amplified into a resonant drone by its swim bladder. Read the guide →
Fish VU Guadalupe Bass Micropterus treculii The Guadalupe bass is found naturally nowhere on Earth except a handful of central Texas rivers, and it is now threatened by hybridization with introduced smallmouth bass stocked in the same waters. Read the guide →
Mammals NT Guadalupe Fur Seal Arctocephalus townsendi The Guadalupe fur seal was hunted to presumed extinction by the early twentieth century, before a small surviving population was rediscovered on one island and slowly rebuilt. Read the guide →
Birds EW Guam Kingfisher Todiramphus cinnamominus The Guam kingfisher has been extinct in the wild since the 1980s after invasive brown tree snakes wiped out Guam's native forest birds, surviving today only through captive breeding. Read the guide →
Birds CR Guam Rail Hypotaenidia owstoni The Guam rail was declared extinct in the wild after invasive brown tree snakes wiped out its island population, only to be brought back through determined captive breeding. Read the guide →
Mammals LC Guanaco Lama guanicoe The guanaco is the wild ancestor of the domestic llama, roaming Patagonian grassland and high Andean terrain in herds while serving as the main prey of the puma across much of its range. Read the guide →
Fish LC Gudgeon Gobio gobio The gudgeon is a small, speckled bottom-dwelling fish with a pair of sensitive barbels at the corners of its mouth, found in shoals over sand and gravel in rivers and lakes across Europe. Read the guide →
Amphibians LC Gulf Coast Toad Incilius nebulifer The Gulf Coast toad adapts readily to suburban yards along the Gulf Coast, breeding in temporary rain pools and defending itself with toxic skin secretions like other true toads. Read the guide →
Amphibians NT Gulf Coast Waterdog Necturus beyeri The Gulf Coast waterdog never grows up in the usual sense, keeping its feathery gills and staying fully aquatic for life in the slow-moving streams of the southeastern coastal plain. Read the guide →
Invertebrates LC Gulf Fritillary Dione vanillae The gulf fritillary depends almost entirely on passionvine, a chemically defended plant, storing the vine's own defensive toxins for its own protection as both caterpillar and adult. Read the guide →
Fish LC Gulf Killifish Fundulus grandis The Gulf killifish is raised commercially in large numbers as live bait, and wild populations survive salt marsh conditions harsh enough to keep most predatory fish away entirely. Read the guide →
Birds NE Gull Laridae A gull, or seagull, is a tough, adaptable seabird that will eat almost anything, from fish and crabs to chips and rubbish, and many species now nest on rooftops far from the coast. Read the guide →
Birds LC Gull-billed Tern Gelochelidon nilotica The gull-billed tern carries a thick, black, gull-like bill instead of the slender pointed bill typical of most terns, and hunts as often over dry land as over water. Read the guide →
Fish LC Gulper Eel Eurypharynx pelecanoides The gulper eel is a deep-sea fish whose enormous, loosely hinged mouth can open wide enough to swallow prey much larger than its own thin, whip-like body. Read the guide →
Fish VU Gulper Shark Centrophorus granulosus The gulper shark's oily, squalene-rich liver made it a target of deep-sea fisheries for decades, a slow-reproducing species whose populations have struggled to recover from historical overfishing. Read the guide →
Invertebrates LC Gumboot Chiton Cryptochiton stelleri The gumboot chiton is the largest chiton in the world, a leathery reddish slab of a mollusc that grazes seaweed off rocks with a tongue tipped in some of the hardest teeth in nature. Read the guide →
Mammals LC Gundi Ctenodactylus gundi The gundi grooms its fur using a built-in comb of stiff bristles on its hind toes, freezing motionless among sun-baked North African rocks rather than fleeing. Read the guide →
Fish LC Gunnel Pholidae A gunnel can survive for hours stranded out of water in a damp tide pool crevice, an eel-like intertidal fish thin enough to hide beneath a single rock while the tide is out. Read the guide →
Fish LC Guppy Poecilia reticulata A guppy is a live-bearing fish from northeastern South America, one of the most popular aquarium fish, a model for studying evolution in the wild, and an invasive pest far outside its home range. Read the guide →
Birds LC Gyrfalcon Falco rusticolus The gyrfalcon is the largest falcon species alive, an Arctic specialist that hunts ptarmigan and waterfowl across open tundra where few other raptors can survive the winter at all. Read the guide →
Fish LC Haddock Melanogrammus aeglefinus The haddock is a major North Atlantic food fish easily identified by a distinctive dark blotch above each pectoral fin, a mark popularly known as the devil's thumbprint or St. Peter's mark. Read the guide →
Invertebrates LC Hag Moth Phobetron pithecium The hag moth caterpillar looks nothing like a typical caterpillar, covered in curling, hair-like projections that make it resemble dead leaves rather than an insect, some carrying a venomous sting. Read the guide →
Fish LC Hagfish Myxini The hagfish is a jawless, eel-shaped survivor from before the age of fish. Attacked, it releases a slime that expands into litres of choking gel in a fraction of a second, clogging a predator's gills. Read the guide →
Amphibians LC Hairy Frog Trichobatrachus robustus The hairy frog breaks its own toe bones and pushes them through its skin as claws when attacked. Breeding males grow hair-like skin strands that work as extra gills while guarding eggs underwater. Read the guide →
Birds LC Hairy Woodpecker Dryobates villosus The hairy woodpecker looks almost exactly like its smaller relative the downy woodpecker, but a longer, heavier bill lets it drill into thicker trunks the smaller bird can't manage. Read the guide →
Mammals LC Hairy-Legged Vampire Bat Diphylla ecaudata The hairy-legged vampire bat feeds almost exclusively on bird blood and is considered the most ancient lineage among the world's three vampire bat species. Read the guide →
Mammals EN Hairy-Nosed Otter Lutra sumatrana The hairy-nosed otter is one of the rarest and least-studied otter species in the world, identified by a fully furred nose unlike the bare noses of its close relatives. Read the guide →
Fish LC Halfbeak Hemiramphidae A halfbeak is a slender surface fish named for its lopsided jaw, in which only the lower half is drawn into a long, needle-like spike while the upper stays short, and several species give live birth. Read the guide →
Invertebrates LC Halloween Pennant Celithemis eponina The Halloween pennant perches loosely at the tip of tall grass or reeds, flagging back and forth in the breeze like a small orange-and-black pennant flying from a pole. Read the guide →
Birds LC Hamerkop Scopus umbretta The hamerkop builds the biggest nest of any bird for its size, a domed fortress of thousands of sticks over a metre across and strong enough to hold a person. A pair builds several a year. Read the guide →
Amphibians VU Hamilton's Frog Leiopelma hamiltoni Hamilton's frog is one of the world's rarest frogs, a survivor of an ancient New Zealand lineage with no tadpole stage and almost no voice, living for decades among the same few rock piles. Read the guide →
Mammals LC Hammer-Headed Bat Hypsignathus monstrosus Male hammer-headed bats gather at nightly display grounds and inflate an oversized larynx to honk for mates, giving Africa's largest bat one of the odder faces in nature. Read the guide →
Mammals LC Hammerhead Bat Hypsignathus monstrosus The male hammerhead bat has an unusually enlarged, box-shaped head housing an oversized voice box, used to produce loud honking calls that attract females over long distances. Read the guide →
Invertebrates NE Hammerhead Flatworm Bipalium The hammerhead flatworm is a long invasive land planarian with a spade-shaped head that hunts earthworms, carries the same nerve poison as a pufferfish, and can regrow from a fragment. Read the guide →
Mammals LC Hanuman Langur Semnopithecus entellus The Hanuman langur is a long-limbed, black-faced monkey of the Indian subcontinent, named for the Hindu monkey god and often living unmolested in temples, villages, and towns. Read the guide →
Mammals LC Harbor Porpoise Phocoena phocoena The harbor porpoise is among the smallest cetaceans, a shy, quick-surfacing species so rarely seen leaping or bow-riding that it often goes unnoticed even in waters where it is genuinely common. Read the guide →
Mammals LC Harbor Seal Phoca vitulina The harbor seal is one of the most widely distributed seal species in the world, a true earless seal often seen resting on rocks and sandbars in coastal waters across both the Atlantic and Pacific. Read the guide →
Mammals LC Hare Lepus A hare is a large, long-legged relative of the rabbit built for open ground and speed, which digs no burrow and bears fully furred young that can run within an hour of birth. Read the guide →
Invertebrates NE Harlequin Beetle Acrocinus longimanus The male harlequin beetle carries front legs longer than its own body, used to grip rivals and mates on fungus-covered trees, beneath a mottled pattern that mimics tree lichen. Read the guide →
Fish LC Harlequin Ghost Pipefish Solenostomus paradoxus The harlequin ghost pipefish drifts like a piece of seagrass or a feather star, a relative of seahorses and pipefish in which the female, not the male, carries the eggs. Read the guide →
Invertebrates NE Harlequin Shrimp Hymenocera picta The harlequin shrimp eats nothing but starfish. A bonded pair hunts together, flips the starfish onto its back, and feeds on it slowly over days, sometimes keeping it alive to stay fresh. Read the guide →
Amphibians CR Harlequin Toad Atelopus Harlequin toads are a genus of roughly 100 brilliantly coloured Central and South American amphibians that has suffered one of the worst disease-driven collapses of any animal group on Earth. Read the guide →
Mammals LC Harp Seal Pagophilus groenlandicus The harp seal is an Arctic seal that breeds on drifting pack ice, where fluffy white pups are weaned in just 12 days on milk 10 times fatter than cow's milk — then abandoned to learn to swim alone. Read the guide →
Birds VU Harpy Eagle Harpia harpyja The harpy eagle is the most powerful raptor in the Americas, with rear talons the size of a bear's claws. It hunts monkeys and sloths in the rainforest canopy and raises one chick every 2–3 years. Read the guide →
Birds LC Harrier Circus A harrier is a slim, long-winged hawk that hunts by quartering low over open marsh and grassland, using an owl-like facial disc to hear prey hidden in the grass below. Read the guide →
Mammals LC Harris's Antelope Squirrel Ammospermophilus harrisii Harris's antelope squirrel stays active through the midday heat of the Sonoran Desert, curling its white-bellied tail over its back like a parasol. Read the guide →
Birds LC Harris's Hawk Parabuteo unicinctus The Harris's hawk is one of the few raptors known to hunt cooperatively in family groups, coordinating like a wolf pack to flush and catch prey. Read the guide →
Birds LC Harris's Sparrow Zonotrichia querula Harris's sparrow is the largest native sparrow in North America, breeding in the Canadian tundra's stunted spruce forest, a region so remote its nest was not documented until the 20th century. Read the guide →
Mammals LC Hartebeest Alcelaphus buselaphus The hartebeest carries an elongated face and ring-shaped horns unlike almost any other antelope, a fast grazer whose subspecies range from common to critically endangered. Read the guide →
Invertebrates LC Harvester Ant Pogonomyrmex The harvester ant clears a bare, circular patch of ground around its nest and delivers one of the most painful stings of any North American insect. Read the guide →
Invertebrates NE Harvestman Opiliones The harvestman, or daddy longlegs, is not a spider and has no venom, despite the famous myth. It is a separate arachnid with one body segment, one pair of eyes, and legs it sheds to escape. Read the guide →
Mammals EN Hawaiian Monk Seal Neomonachus schauinslandi The Hawaiian monk seal is found nowhere else on Earth outside the Hawaiian archipelago, one of the most endangered seals in the world, now the focus of an active rescue and rehabilitation program. Read the guide →
Birds LC Hawfinch Coccothraustes coccothraustes The hawfinch has a bite powerful enough to crack cherry and olive stones, one of the strongest bills relative to size of any European songbird. Read the guide →
Birds NE Hawk Accipiter and Buteo A hawk is a medium-sized day-hunting bird of prey in two main styles — short-winged forest hawks that ambush birds, and broad-winged open-country hawks that soar and drop on rodents. Read the guide →
Fish LC Hawkfish Cirrhitidae The hawkfish perches motionless on coral or rock like a hawk on a branch, lacking the swim bladder most fish use to float, and instead waiting to ambush passing prey. Read the guide →
Reptiles CR Hawksbill Sea Turtle Eretmochelys imbricata The hawksbill is a small, beautifully patterned sea turtle that eats mainly sponges — including toxic ones — and helps keep coral reefs healthy. The tortoiseshell trade made it Critically Endangered. Read the guide →
Invertebrates NE Hawthorn Shield Bug Acanthosoma haemorrhoidale The hawthorn shield bug is a green, shield-shaped bug with a reddish-brown patch and reddish wing tips that sucks sap and berries from hawthorn and other trees and overwinters as an adult. Read the guide →
Mammals NT Hazel Dormouse Muscardinus avellanarius The hazel dormouse spends more than half the year in hibernation, waking only for a brief summer window to feed, breed, and fatten up before sleeping again. Read the guide →
Invertebrates LC Heart Urchin Echinocardium The heart urchin abandons the round, radial body plan of a typical sea urchin for a bilaterally symmetric, heart-shaped test built for burrowing through sand rather than grazing exposed rock. Read the guide →
Mammals NT Heaviside's Dolphin Cephalorhynchus heavisidii Heaviside's dolphin is found only along a narrow, cold stretch of southwestern African coast, one of the smallest dolphin species, named after the collector who supplied its first specimen. Read the guide →
Mammals DD Hector's Beaked Whale Mesoplodon hectori Hector's beaked whale is one of the smallest members of its genus, a rarely seen deep-diving whale of the Southern Hemisphere known mostly from a limited number of strandings. Read the guide →
Mammals EN Hector's Dolphin Cephalorhynchus hectori Hector's dolphin has a rounded dorsal fin shaped like a mouse's ear rather than the pointed fin of most dolphins, one of the smallest and rarest dolphin species, found only around New Zealand. Read the guide →
Mammals NE Hedgehog Erinaceidae A hedgehog is a small nocturnal mammal covered in thousands of hollow spines that it draws into a near-impregnable ball when threatened, and one of the few British mammals that truly hibernates. Read the guide →
Amphibians NT Hellbender Cryptobranchus alleganiensis The hellbender is North America's largest salamander, a flat, wrinkled river-dweller up to 70 cm long that breathes through its skin and needs some of the cleanest water on the continent. Read the guide →
Birds VU Helmet Vanga Euryceros prevostii The helmet vanga carries one of the largest, most vividly coloured bills relative to body size of any songbird, a pale blue casque above a black face and chestnut body. Read the guide →
Birds CR Helmeted Hornbill Rhinoplax vigil The helmeted hornbill is the only hornbill with a solid casque, a keratin block a tenth of its weight that it swings in mid-air jousts. Poaching for that ivory has made it Critically Endangered. Read the guide →
Amphibians VU Helmeted Water Toad Calyptocephalella gayi The helmeted water toad of central Chile is one of the world's largest frogs and eats fish, birds, and other frogs. It is also the last of a frog family over 100 million years old. Read the guide →
Birds NT Henslow's Sparrow Centronyx henslowii Henslow's sparrow delivers one of the weakest songs of any North American bird, a barely audible hiccup, yet its dependence on undisturbed tallgrass has made it a grassland conservation priority. Read the guide →
Invertebrates LC Hercules Beetle Dynastes hercules The Hercules beetle is the longest beetle in the world — the male's horn nearly doubles his body length — and among the strongest animals for its size. Its shell changes colour with humidity. Read the guide →
Invertebrates NE Hercules Moth Coscinocera hercules The Hercules moth is a huge Australasian silk moth with the largest wing area of any moth, whose males have long tails and whose adults, with no mouth, live only a week or two. Read the guide →
Reptiles NT Hermann's Tortoise Testudo hermanni Hermann's tortoise is a small, hardy Mediterranean tortoise that spends much of the year basking, grazing, and dormant through both winter cold and summer heat. Read the guide →
Invertebrates NE Hermit Crab Paguroidea The hermit crab has a soft, spiralled abdomen and no shell of its own, so it lives in an empty snail shell and trades up as it grows. When a better shell turns up, crabs queue by size to swap. Read the guide →
Birds LC Hermit Thrush Catharus guttatus The hermit thrush is the only member of its genus that winters in North America instead of the tropics, and its clear, flute-like song ranks among the most beautiful of any North American bird. Read the guide →
Mammals LC Hero Shrew Scutisorex somereni The hero shrew has an interlocking, girder-like backbone so strong that a grown man can stand on the animal without harming it, an anatomy found in no other mammal. Read the guide →
Birds NE Heron Ardeidae A heron is a long-legged wading bird that hunts by standing still in shallow water and then striking with a neck that unfolds like a spring, driving a dagger bill into fish, frogs, and voles. Read the guide →
Fish LC Herring Clupea harengus The herring is a small silver fish that swims in schools of billions and shaped the history of northern Europe. It seems to keep its school together in the dark by venting bubbles from its rear end. Read the guide →
Birds LC Herring Gull Larus argentatus The herring gull is the classic large gull of northern coastlines, a bold, opportunistic scavenger with a yellow bill and red spot that chicks peck to trigger feeding. Read the guide →
Amphibians VU Hickory Nut Gorge Green Salamander Aneides caryaensis The Hickory Nut Gorge green salamander was only recognised as its own species in 2021, split from the widespread green salamander after genetic studies showed it had been evolving separately. Read the guide →
Birds LC Himalayan Monal Lophophorus impejanus The Himalayan monal shifts through green, purple, copper, and blue as it moves, its iridescent male plumage changing colour with the angle of the light rather than staying fixed. Read the guide →
Amphibians VU Hip-pocket Frog Assa darlingtoni The hip-pocket frog is a tiny Australian rainforest frog in which the father carries his tadpoles inside a pair of skin pockets on his hips until they crawl out as fully formed froglets. Read the guide →
Mammals VU Hippopotamus Hippopotamus amphibius The hippopotamus spends its days in water and its nights grazing on land, sweats a red antibiotic sunscreen, and is one of Africa's most dangerous animals. Learn how this river giant lives. Read the guide →
Mammals CR Hirola Beatragus hirola The hirola is the world's most endangered antelope, with fewer than 500 left in the wild, nicknamed the "four-eyed antelope" for large glands below its eyes that resemble a second pair. Read the guide →
Mammals EN Hispid Hare Caprolagus hispidus The hispid hare carries coarse, bristly fur and unusually short ears and legs for a hare, surviving in dwindling patches of tall Himalayan foothill grassland. Read the guide →
Mammals LC Hoary Bat Lasiurus cinereus The hoary bat migrates long distances and roosts alone in tree foliage rather than caves, a frosty-furred bat whose turbine collisions have made it one of the species most affected by wind energy. Read the guide →
Mammals LC Hoary Marmot Marmota caligata The hoary marmot is a large, silvery-shouldered alpine marmot of northwestern North America whose shrill alarm whistle gave Whistler, British Columbia, its name. Read the guide →
Birds LC Hoatzin Opisthocomus hoazin The hoatzin is a strange Amazonian bird that digests leaves in a cow-like foregut, smells of manure, and whose chicks have working claws on their wings for climbing. Read the guide →
Invertebrates NE Hoff Crab Kiwa tyleri The Hoff crab grows dense bristles across its chest rather than just its claws, farming bacteria on them and gathering by the hundreds of thousands around deep-sea hydrothermal vents. Read the guide →
Mammals VU Hog Badger Arctonyx collaris The hog badger roots through soil and leaf litter with an elongated, pig-like snout, an Asian relative of true badgers hunted heavily for meat and traditional medicine. Read the guide →
Fish VU Hogfish Lachnolaimus maximus The hogfish is a large, colour-changing wrasse named for its elongated, pig-like snout, and every individual begins life as a female before some later transform into males. Read the guide →
Reptiles NE Hognose Snake Heterodon A hognose snake is a stout North American burrower with an upturned snout for digging, a spectacular bluffing display of hooding and hissing, and, if that fails, a convincing act of playing dead. Read the guide →
Invertebrates LC Holly Blue Celastrina argiolus The holly blue is a silvery-blue butterfly of hedges and gardens with two broods a year, the spring one laying on holly and the summer one on ivy, and it flutters high around shrubs and trees. Read the guide →
Mammals NT Honduran White Bat Ectophylla alba The Honduran white bat is a tiny snow-white rainforest bat that bites the ribs of a large leaf so it folds into a tent, then roosts underneath in a huddle that glows faintly green. Read the guide →
Mammals LC Honey Badger Mellivora capensis The honey badger has loose armour-like skin, partial resistance to snake venom, and a documented talent for escaping any enclosure. Learn why it takes on cobras, lions, and beehives. Read the guide →
Fish LC Honey Gourami Trichogaster chuna The honey gourami is one of the smallest and most peaceful gouramis kept in aquariums, with breeding males turning a warm honey-orange colour rarely seen outside the courtship season. Read the guide →
Mammals LC Honey Possum Tarsipes rostratus The honey possum is a mouse-sized Australian marsupial that eats only nectar and pollen, has almost no teeth left, and produces the longest sperm of any known mammal. Read the guide →
Invertebrates NE Honeybee Apis mellifera The honeybee runs a colony of tens of thousands, navigates by the sun, and tells hivemates where to find flowers with a dance. Learn how the hive works and what's behind the decline in bee health. Read the guide →
Birds LC Honeyeater Meliphagidae The honeyeater carries a brush-tipped tongue built for mopping up flower nectar, one of the most diverse bird families in Australia and a major pollinator across the continent's native plant life. Read the guide →
Invertebrates NE Honeypot Ant Myrmecocystus mexicanus In a honeypot ant colony some workers become living storage jars, force-fed sugary liquid until the abdomen swells to a grape. They hang from the nest ceiling and feed the colony through drought. Read the guide →
Birds CR Hooded Grebe Podiceps gallardoi The hooded grebe performs an elaborate synchronized courtship dance on remote Patagonian plateau lakes, a ritual now threatened by introduced predators. Read the guide →
Invertebrates NE Hooded Nudibranch Melibe leonina The hooded nudibranch catches prey with an oversized, net-like hood instead of the radula most sea slugs use, swinging it through the water to trap small crustaceans. Read the guide →
Birds LC Hooded Pitohui Pitohui dichrous The hooded pitohui is one of very few birds known to be poisonous, carrying the same nerve toxin as poison dart frogs in its skin and feathers, acquired from the beetles it eats. Read the guide →
Mammals VU Hooded Seal Cystophora cristata The hooded seal produces the richest milk of any mammal and weans its pup in just four days, the shortest nursing period known, with the pup tripling its birth weight almost entirely on fat. Read the guide →
Birds LC Hooded Warbler Setophaga citrina The male hooded warbler wears a striking black hood around a bright yellow face, and both sexes flash white outer tail feathers that may startle hidden insects into flight. Read the guide →
Birds LC Hornbill Bucerotidae A hornbill is a large Old World forest bird with a long down-curved bill topped by a hollow casque, and in most species the female seals herself inside a tree hole with mud to raise the chicks. Read the guide →
Amphibians NE Horned Frog Ceratophryidae A horned frog is a South American ambush hunter that is almost all mouth, buries itself with only its eyes showing, and will lunge at and try to swallow prey nearly as large as itself. Read the guide →
Birds LC Horned Lark Eremophila alpestris The horned lark is the only true lark native to North America, named for small feather tufts on its head, and forms enormous mixed winter flocks with longspurs and snow buntings. Read the guide →
Reptiles LC Horned Lizard Phrynosoma A horned lizard is a flat, spiky desert lizard of the Americas that eats mostly ants, freezes rather than flees, puffs up to avoid being swallowed, and can squirt foul blood from its eye sockets. Read the guide →
Reptiles LC Horned Viper Cerastes cerastes The horned viper is a Saharan ambush predator named for the horn-like scales above each eye, crossing loose desert sand with a sideways sidewinding motion that leaves a distinctive J-shaped trail. Read the guide →
Invertebrates NE Horsehair Worm Nematomorpha The horsehair worm is a hair-thin parasite up to a metre long that grows inside a cricket, then hijacks its brain and drives the insect to drown itself so the worm can escape into water. Read the guide →
Invertebrates VU Horseshoe Crab Xiphosura A horseshoe crab is a helmet-shaped marine arthropod barely changed in 400 million years, closer kin to spiders than crabs, with blue blood the drug industry harvests to test for contamination. Read the guide →
Reptiles LC Horseshoe Whip Snake Hemorrhois hippocrepis The horseshoe whip snake is a fast, slender, non-venomous snake of Iberia and North Africa with a horseshoe-shaped mark on its neck, a quick hunter of lizards and rodents on dry, rocky ground. Read the guide →
Mammals VU Horsfield's Tarsier Cephalopachus bancanus Horsfield's tarsier is a Vulnerable Southeast Asian primate with eyes as large as its brain that rotates its head almost all the way round and leaps onto insects and small vertebrates at night. Read the guide →
Mammals LC Hourglass Dolphin Lagenorhynchus cruciger The hourglass dolphin displays a black-and-white pattern that narrows sharply along its sides, a small, fast species found in some of the coldest, remotest waters near Antarctica. Read the guide →
Amphibians LC Hourglass Tree Frog Dendropsophus ebraccatus The hourglass tree frog is one of the only amphibians known to switch egg-laying strategy by risk, laying eggs on land in some ponds and directly in the water in others. Read the guide →
Invertebrates NE House Centipede Scutigera coleoptrata The house centipede is the fast, alarming, many-legged animal that appears in bathrooms and basements. It runs at over 40 cm per second and hunts cockroaches, silverfish, and spiders. Read the guide →
Birds LC House Finch Haemorhous mexicanus A male house finch's red coloring comes directly from pigments in its diet, meaning the reddest males are often simply the best foragers. Read the guide →
Mammals LC House Mouse Mus musculus The house mouse is a small rodent that has followed people around the world since the first grain stores, breeds fast enough to fill a building in a year, and is the key mammal of medical research. Read the guide →
Birds LC House Sparrow Passer domesticus The house sparrow is the small brown bird that follows people almost everywhere on Earth, from farmyards to city centres, yet it has vanished from many European cities in the past few decades. Read the guide →
Amphibians EN Houston Toad Anaxyrus houstonensis The Houston toad is a Critically Endangered amphibian confined to a shrinking patch of Texas pine forest, one of the very first species protected under the US Endangered Species Act. Read the guide →
Invertebrates LC Hover Fly Syrphidae The hover fly mimics the black-and-yellow warning pattern of bees and wasps despite having no stinger, and it hangs motionless in mid-air far better than either. Read the guide →
Mammals LC Howler Monkey Alouatta The howler monkey is the loudest land animal in the Americas, its dawn roar carrying up to 5 km through the forest. A hollow throat bone acts as a resonating chamber. Read the guide →
Fish EN Huchen Hucho hucho The huchen, or Danube salmon, is a huge, torpedo-shaped predator of clean, cold Danube rivers, one of the largest salmon relatives in the world and now endangered by dams and pollution. Read the guide →
Mammals EN Huemul Hippocamelus bisulcus The huemul appears on Chile's national coat of arms alongside the condor, yet survives today in only a fraction of its historical range across the southern Andes. Read the guide →
Birds EX Huia Heteralocha acutirostris The huia was a New Zealand wattlebird in which the male and female had completely different bills. Hunted for its tail feathers and its skins, it was last seen for certain in 1907. Read the guide →
Amphibians CR Hula Painted Frog Latonia nigriventer The Hula painted frog was declared extinct in 1996, rediscovered in an Israeli marsh in 2011, and then found to be the only living member of a frog genus otherwise known only from fossils. Read the guide →
Birds VU Humboldt Penguin Spheniscus humboldti The Humboldt penguin lives along the desert coastline of South America, kept cool by a cold ocean current rather than any polar climate, nesting in burrows dug into ancient seabird droppings. Read the guide →
Invertebrates NE Humboldt Squid Dosidicus gigas The Humboldt squid is a large, fast-growing predatory squid of the eastern Pacific that hunts in flashing coordinated groups, dives into near-oxygen-free water by day, and lives barely a year or two. Read the guide →
Birds NE Hummingbird Trochilidae A hummingbird is the smallest of all birds, able to hover, fly backwards, and beat its wings up to 80 times a second, running an engine so hot it must shut down into torpor most nights to survive. Read the guide →
Invertebrates LC Hummingbird Clearwing Moth Hemaris thysbe The hummingbird clearwing moth hovers at flowers in daylight, beating its wings so fast that scales rub away to leave clear patches, resulting in a moth convincing enough to fool attentive observers. Read the guide →
Invertebrates NE Hummingbird Hawk-moth Macroglossum stellatarum The hummingbird hawk-moth hovers at flowers in broad daylight, wings a blur, feeding through a long tongue exactly like a hummingbird. People regularly report hummingbird sightings where none exist. Read the guide →
Mammals LC Humpback Whale Megaptera novaeangliae The humpback whale sings songs that evolve and spread across oceans, blows nets of bubbles to trap fish, and migrates up to 8,000 km between polar feeding grounds and tropical breeding waters. Read the guide →
Fish NT Humped Rockcod Gobionotothen gibberifrons The humped rockcod is a bottom-dwelling Antarctic fish named for the distinctive raised hump behind its head, historically an important target of early Southern Ocean commercial fisheries. Read the guide →
Fish EN Humphead Wrasse Cheilinus undulatus The humphead wrasse is one of the largest reef fish — up to 2 m and 190 kg — with a bulging forehead and thick lips. It eats urchins and toxic prey others avoid, and switches from female to male. Read the guide →
Invertebrates NE Huntsman Spider Sparassidae A huntsman spider is a fast, flat-bodied spider that holds its legs out crab-fashion, builds no web, and hunts by running prey down; it is the harmless spider that sprints across an Australian wall. Read the guide →
Amphibians LC Hurter's Spadefoot Scaphiopus hurterii Hurter's spadefoot spends nearly its entire life buried underground, emerging only after heavy rain to breed in an explosive, short-lived burst of activity in temporary pools. Read the guide →
Birds VU Hyacinth Macaw Anodorhynchus hyacinthinus The hyacinth macaw is the longest parrot species in the world, wielding a bite powerful enough to crack the hardest palm nuts that most other animals in its habitat cannot even dent. Read the guide →
Invertebrates NE Hydra Hydra A hydra is a tiny freshwater relative of jellyfish, a stalk of tentacles a few millimetres long that catches prey with stinging cells, clones itself by budding, and appears to barely age at all. Read the guide →
Invertebrates NE Hydroid Hydrozoa The hydroid grows as a plant-like colony of tiny stinging polyps attached to rocks and docks, so easily mistaken for seaweed that most people never realise they're looking at a colonial animal at all. Read the guide →
Mammals VU Iberian Lynx Lynx pardinus The Iberian lynx fell to about 100 animals in 2002 and was the most endangered cat in the world. Captive breeding and reintroduction have since rebuilt it to more than 2,000. Read the guide →
Amphibians NT Iberian Ribbed Newt Pleurodeles waltl Threatened, the Iberian ribbed newt pushes its sharp rib tips out through poison glands in its own skin, turning its flanks into a bank of venom-tipped spines. It has flown on the ISS. Read the guide →
Amphibians LC Iberian Water Frog Pelophylax perezi The Iberian water frog stays active and calling through the hottest, driest Iberian summers that send most other frogs into hiding, thriving in irrigation ditches and farm ponds most amphibians avoid. Read the guide →
Fish LC Icefish Channichthyidae An icefish is the only known vertebrate that survives without haemoglobin, giving it nearly clear, white blood, an adaptation that lets it thrive in freezing Antarctic waters few fish tolerate. Read the guide →
Invertebrates LC Ichneumon Wasp Ichneumonidae The ichneumon wasp often carries an ovipositor several times its own body length, an intimidating drill used to lay eggs deep inside hidden host insects. Read the guide →
Amphibians NT Idaho Giant Salamander Dicamptodon aterrimus The Idaho giant salamander lives landlocked in the Rocky Mountains, hundreds of miles from its coastal relatives, a leftover population stranded when its family's continuous range broke apart. Read the guide →
Fish LC Ide Leuciscus idus The ide, or orfe, is a deep-bodied, silvery shoaling fish of northern and eastern European rivers and lakes whose golden form, the golden orfe, is a favourite of garden ponds. Read the guide →
Reptiles NE Iguana Iguanidae An iguana is a large American lizard with a spiny crest and a throat fan that, unusually for a lizard, eats almost only leaves, ferments them with gut microbes, and basks for hours to power it. Read the guide →
Amphibians NT Illinois Chorus Frog Pseudacris illinoensis The Illinois chorus frog spends most of the year buried in sandy soil, a burrowing frog whose musical, bell-like trill briefly announces its presence each spring before disappearing again. Read the guide →
Amphibians LC Imitator Salamander Desmognathus imitator The imitator salamander is a harmless species that mimics the appearance of a genuinely toxic neighbour, borrowing protection it never actually earned through its own chemistry. Read the guide →
Invertebrates NE Immortal Jellyfish Turritopsis dohrnii The immortal jellyfish can reverse its life cycle — an adult under stress collapses into a blob and regrows as a juvenile polyp, in principle without limit. It is about the size of a pinhead. Read the guide →
Mammals LC Impala Aepyceros melampus The impala is the antelope of the African savanna edge, able to clear 10 metres in a bound. It switches between grazing and browsing as the seasons turn, which is why it thrives where others fail. Read the guide →
Invertebrates LC Imperial Moth Eacles imperialis The imperial moth is one of the largest moths in North America, a yellow-and-purple giant whose caterpillar varies so much in colour that siblings from the same clutch can look like different species. Read the guide →
Birds LC Imperial Shag Leucocarbo atriceps The imperial shag has a striking blue ring of bare skin around each eye and dives to considerable depth in pursuit of fish, nesting in dense colonies on rocky sub-Antarctic coastlines. Read the guide →
Birds EX Imperial Woodpecker Campephilus imperialis The imperial woodpecker was the largest woodpecker that ever lived, a giant of Mexico's mountain pine forests believed to have gone extinct after old-growth logging. Read the guide →
Birds VU Inaccessible Island Rail Laterallus rogersi The Inaccessible Island rail is the smallest flightless bird alive, confined to a single remote South Atlantic island whose steep cliffs gave the island, and the bird, its name. Read the guide →
Reptiles LC Indian Cobra Naja naja The Indian cobra is one of the "big four" snakes behind most of India's snakebite deaths. It spreads a spectacle-marked hood, and it is the snake of charmers' baskets and Hindu myth. Read the guide →
Mammals LC Indian Flying Fox Pteropus giganteus The Indian flying fox roosts by day in colonies of thousands hanging from treetops, one of the largest bats in the world and a vital pollinator across South Asia's forests. Read the guide →
Mammals LC Indian Giant Squirrel Ratufa indica The Indian giant squirrel is a huge, multicoloured tree squirrel of India's forests, with a tail longer than its body, spending nearly its whole life high in the canopy. Read the guide →
Mammals LC Indian Grey Mongoose Herpestes edwardsii The Indian grey mongoose is the real-world inspiration behind Rudyard Kipling's cobra-fighting hero Rikki-Tikki-Tavi, long valued around South Asian homes for keeping snakes and rodents away. Read the guide →
Mammals LC Indian Palm Squirrel Funambulus palmarum The Indian palm squirrel carries three pale stripes down its back that, in a Hindu legend, were left by the fingers of Lord Rama, and thrives in gardens and cities across India. Read the guide →
Mammals EN Indian Pangolin Manis crassicaudata The Indian pangolin is an Endangered, armoured anteater of the Indian subcontinent that digs deep burrows, curls into a ball when threatened, and is hunted for its scales and meat. Read the guide →
Birds LC Indian Peafowl Pavo cristatus The peacock's train is not its tail — it is up to 200 elongated back feathers that the bird fans, rattles, and vibrates 25 times a second in a display Darwin found so extravagant it "made him sick". Read the guide →
Reptiles NT Indian Rock Python Python molurus The Indian rock python is a heavy, pale-blotched constrictor of South Asia whose brooding mother shivers to warm her eggs, and which has declined as its grassland and marsh habitats have been lost. Read the guide →
Reptiles VU Indian Star Tortoise Geochelone elegans The Indian star tortoise has a domed shell decorated with radiating yellow stars on black, a pattern that is real camouflage in dry grass, and it is the most heavily trafficked tortoise in the world. Read the guide →
Birds LC Indigo Bunting Passerina cyanea The indigo bunting has no blue pigment in its feathers at all, its brilliant colour created entirely by light scattering off microscopic feather structure, a trick of physics rather than paint. Read the guide →
Reptiles LC Indigo Snake Drymarchon An indigo snake is a big, glossy blue-black non-venomous American snake. The eastern indigo is the longest native snake in the US, eats rattlesnakes, and shelters in gopher tortoise burrows. Read the guide →
Mammals CR Indri Indri indri The indri is the largest living lemur and sings loud, wailing songs that carry for kilometres through the rainforest, a species that has never survived long in captivity. Read the guide →
Mammals EN Indus River Dolphin Platanista minor The Indus river dolphin survives in only a fraction of its range, isolated into fragmented river stretches by irrigation barrages, a functionally blind species among the rarest freshwater cetaceans. Read the guide →
Reptiles LC Inland Taipan Oxyuranus microlepidotus The inland taipan has the most toxic venom of any land snake — one bite could kill dozens — yet it is shy, remote, and reclusive, and has never caused a recorded human death. Read the guide →
Invertebrates NE Innkeeper Worm Urechis caupo The innkeeper worm is a fat pink marine worm that lives in a U-shaped burrow, feeds by pumping seawater through a mucus net it eats whole, and rents out spare rooms to crabs, fish, and clams. Read the guide →
Amphibians VU Inyo Mountains Salamander Batrachoseps campi The Inyo Mountains salamander survives in desert canyon seeps within one of the driest mountain ranges in North America, a lungless amphibian clinging to life wherever a spring breaks the surface. Read the guide →
Invertebrates LC Io Moth Automeris io The io moth flashes two enormous blue-black eyespots to startle predators, while its green caterpillar carries venomous spines delivering a genuinely painful sting. Read the guide →
Fish LC Iowa Darter Etheostoma exile The Iowa darter tolerates colder water than most of its darter relatives, and breeding males flush a vivid blue-green and orange-red pattern in glacial lakes and cool northern streams. Read the guide →
Mammals EN Irrawaddy Dolphin Orcaella brevirostris The Irrawaddy dolphin has a rounded, beakless head giving it an almost whale-like look, a species of coastal and river waters in Southeast Asia known for cooperating with fishers to herd fish. Read the guide →
Invertebrates NE Irukandji Jellyfish Carukia barnesi and relatives The Irukandji jellyfish is barely bigger than a fingernail, but its sting triggers hours of agonising pain and a sense of impending doom severe enough that victims sometimes beg for sedation. Read the guide →
Invertebrates LC Isabella Tiger Moth Pyrrharctia isabella The Isabella tiger moth's fuzzy woolly bear caterpillar can survive being frozen solid through an entire winter, and folk tradition claims its band widths predict how harsh that winter will be. Read the guide →
Birds LC Island Canary Serinus canaria The wild island canary is a muted yellowish-green, and every vividly yellow pet canary today descends from generations of selective breeding from it. Read the guide →
Mammals NT Island Fox Urocyon littoralis The island fox evolved into a dwarf form on California's Channel Islands and nearly went extinct in the early 2000s, before one of the fastest recoveries ever recorded for an endangered mammal. Read the guide →
Reptiles LC Island Glass Lizard Ophisaurus compressus The island glass lizard has no legs at all yet is not a snake, a legless lizard with movable eyelids and external ear openings that give it away the moment it stops moving. Read the guide →
Reptiles LC Island Night Lizard Xantusia riversiana The island night lizard survives only on a handful of California's Channel Islands, a population once pushed to the brink that has since become a rare reptile conservation success story. Read the guide →
Amphibians LC Italian Crested Newt Triturus carnifex The Italian crested newt grows a dramatic jagged crest along its back during the breeding season, a striking seasonal display that vanishes again once the newt returns to life on land each year. Read the guide →
Amphibians LC Italian Newt Lissotriton italicus The Italian newt is the smallest newt species in Europe, a tiny southern Italian amphibian that breeds in shallow, often temporary pools and can mature within its very first year of life. Read the guide →
Amphibians LC Italian Stream Frog Rana italica The Italian stream frog lives right along the banks of fast, rocky streams rather than ponds, and escapes danger by diving straight into the current and wedging itself under a submerged rock. Read the guide →
Reptiles LC Italian Wall Lizard Podarcis siculus The Italian wall lizard is a quick, adaptable lizard of southern Europe that has been introduced to many places, and one introduced population evolved a plant-digesting gut in a few decades. Read the guide →
Birds NT Ivory Gull Pagophila eburnea The ivory gull is almost entirely pure white from head to tail, a high Arctic specialist that follows polar bears across the pack ice to scavenge the leftovers of their seal kills. Read the guide →
Birds CR Ivory-billed Woodpecker Campephilus principalis The ivory-billed woodpecker was once so striking that people reportedly exclaimed "Lord God!" upon seeing one, a bird now Critically Endangered and possibly extinct. Read the guide →
Invertebrates LC Ivory-Marked Beetle Eburia quadrigeminata The ivory-marked beetle can spend years developing inside dry hardwood before finally emerging as an adult, sometimes chewing its way out of furniture or flooring built from wood cut years earlier. Read the guide →
Birds LC Jabiru Jabiru mycteria The jabiru is the tallest flying bird in the Americas, an enormous white stork with a bare black head and a bright red band circling its neck like a piece of jewelry. Read the guide →
Birds LC Jacamar Galbulidae A jacamar is an iridescent tropical bird that catches butterflies and dragonflies in mid-air, then beats its prey against a branch to remove wings and stingers before swallowing it. Read the guide →
Fish LC Jack Carangidae A jack is a fast, powerfully built open-water predator with a deeply forked tail and a stiff, streamlined body built almost entirely for sustained high-speed pursuit of schooling prey fish. Read the guide →
Fish LC Jack Dempsey Rocio octofasciata The Jack Dempsey cichlid was named after a heavyweight boxing champion for its pugnacious temperament, transforming from a drab grey juvenile into an adult spangled with iridescent blue-green flecks. Read the guide →
Invertebrates NE Jack Jumper Ant Myrmecia pilosula The jack jumper ant is an aggressive Australian bull ant that leaps at intruders, with a sting that can cause severe allergic reactions and males that carry just a single chromosome. Read the guide →
Birds LC Jackdaw Corvus monedula The jackdaw is the smallest of the European crows, a sociable grey-naped black bird with a pale staring eye that lives in noisy flocks, nests in chimneys and cliffs, and pairs for life. Read the guide →
Reptiles LC Jackson's Chameleon Trioceros jacksonii The male Jackson's chameleon has three forward-pointing horns like a tiny Triceratops, used to wrestle rivals off branches. A pet-trade release in the 1970s founded a wild population in Hawaii. Read the guide →
Mammals LC Jackson's Mongoose Bdeogale jacksoni Jackson's mongoose lives in the cool montane forests of East Africa, a poorly studied relative of the bushy-tailed mongoose known mainly from scattered highland records. Read the guide →
Mammals NT Jaguar Panthera onca The jaguar is the biggest cat in the Americas and has the strongest bite of any big cat for its size — it kills by piercing the skull. Learn how it hunts in water and why it's Near Threatened. Read the guide →
Mammals LC Jaguarundi Herpailurus yagouaroundi The jaguarundi looks so unlike a typical wild cat, with a long, low body and small ears, that it is often mistaken for a weasel or otter, an active daytime hunter unlike most nocturnal relatives. Read the guide →
Mammals LC Jamaican Fruit Bat Artibeus jamaicensis The Jamaican fruit bat is a common Neotropical leaf-nosed bat that eats figs and other fruit and scatters their seeds, helping to regrow tropical forests. Read the guide →
Reptiles CR Jamaican Iguana Cyclura collei The Jamaican iguana is a Critically Endangered rock iguana thought extinct until a hunter found one in 1990, now surviving in Jamaica's Hellshire Hills with the help of a head-start programme. Read the guide →
Birds NT James's Flamingo Phoenicoparrus jamesi James's flamingo was believed extinct for decades before a breeding colony was rediscovered on a remote high-Andean salt lake, and it remains the smallest of the world's flamingo species. Read the guide →
Invertebrates LC Japanese Beetle Popillia japonica A single damaged leaf releases a scent that draws in more Japanese beetles to the same plant, turning one insect's meal into a rapidly growing group that can strip a shrub bare within days. Read the guide →
Amphibians NT Japanese Fire-belly Newt Cynops pyrrhogaster The Japanese fire-belly newt carries tetrodotoxin, the same lethal poison as a pufferfish, and flashes its scarlet belly as a warning. It can regenerate a leg, an eye lens, or heart tissue repeatedly. Read the guide →
Amphibians VU Japanese Giant Salamander Andrias japonicus The Japanese giant salamander is the world's second-largest amphibian — up to 1.5 m of wrinkled, slime-covered skin — living for decades in cold mountain streams and breathing through its body. Read the guide →
Mammals LC Japanese Macaque Macaca fuscata The Japanese macaque is the northernmost primate other than humans, surviving winters of —20 °C by soaking in volcanic hot springs. Its behaviours spread through troops like culture. Read the guide →
Reptiles LC Japanese Mamushi Gloydius blomhoffii The Japanese mamushi is a small, brown-ringed pit viper of Japan's forests, fields, and rice paddies, a leading cause of snakebite in Japan and a famous ingredient in traditional medicinal liquor. Read the guide →
Invertebrates LC Japanese Spider Crab Macrocheira kaempferi The Japanese spider crab has the largest leg span of any arthropod — up to 3.7 metres claw to claw. It lives on the deep seabed off Japan and may reach 100 years old. Read the guide →
Amphibians LC Japanese Tree Frog Dryophytes japonicus A Japanese tree frog is a small green tree frog of East Asian rice paddies whose night chorus fills the countryside, and whose call timing has been studied to design better wireless networks. Read the guide →
Invertebrates LC Japetella Japetella diaphana Japetella changes from a transparent juvenile into a dark reddish-brown adult, a gelatinous deep-sea octopus that swaps camouflage for confusing predators with its own bioluminescent glow. Read the guide →
Reptiles LC Jararaca Bothrops jararaca The jararaca is the pit viper responsible for most snakebites in southeastern Brazil, and the drug that its venom led scientists to, captopril, was the first of the modern blood-pressure pills. Read the guide →
Birds LC Jay Garrulus and relatives A jay is a colourful, noisy woodland member of the crow family that buries thousands of acorns and pine seeds each autumn and forgets enough of them to plant whole forests. Read the guide →
Amphibians LC Jefferson Salamander Ambystoma jeffersonianum The Jefferson salamander is a slender mole salamander of eastern North American woods that breeds in icy vernal pools in late winter, and its ponds hold an ancient all-female salamander lineage. Read the guide →
Invertebrates NE Jellyfish Medusozoa A jellyfish is a drifting predator that is about 95 per cent water, has no brain, heart, blood, or bones, and fires microscopic harpoons from its tentacles to sting and haul in prey. Read the guide →
Amphibians VU Jemez Mountains Salamander Plethodon neomexicanus The Jemez Mountains salamander survives within one volcanic caldera complex in New Mexico, an entire species confined to underground rock fractures formed by ancient eruptions millions of years ago. Read the guide →
Invertebrates NE Jersey Tiger Euplagia quadripunctaria The Jersey tiger is a day-flying tiger moth with black-and-cream striped forewings and flashing orange-red hindwings, famous for the thousands that gather in the Valley of the Butterflies on Rhodes. Read the guide →
Invertebrates LC Jerusalem Cricket Ammopelmatus The Jerusalem cricket is a large, flightless, humanoid-headed insect of the western US that lives underground, courts by drumming its belly on the soil, and is neither from Jerusalem nor a cricket. Read the guide →
Invertebrates LC Jewel Beetle Buprestidae The jewel beetle's dazzling metallic colours come from microscopic structural layers bending light, not pigment, and some species can detect infrared heat from forest fires miles away. Read the guide →
Fish LC Jewel Cichlid Hemichromis bimaculatus The jewel cichlid flushes a brilliant red studded with iridescent blue spangles when breeding, a burst of colour matched by some of the most aggressive parental defence in the aquarium hobby. Read the guide →
Invertebrates NE Jewel Wasp Ampulex compressa The jewel wasp turns a cockroach into living larva food with two precise brain stings that remove its will to flee, then leads the docile roach into a burrow by its antenna, like walking a dog. Read the guide →
Fish LC John Dory Zeus faber The John Dory is so thin from the side it nearly vanishes head-on, drifting up to prey before firing out a mouth that unfolds to nearly its own body width. A ringed flank spot mimics a false eye. Read the guide →
Fish LC Johnny Darter Etheostoma nigrum The johnny darter is one of the most widespread and tolerant darters in North America, with males guarding a clutch of eggs glued upside down to the underside of a rock. Read the guide →
Amphibians VU Jollyville Plateau Salamander Eurycea tonkawae The Jollyville Plateau salamander lives in springs and caves near fast-growing Austin, Texas, one of the few salamanders whose survival depends directly on urban groundwater management. Read the guide →
Amphibians LC Jordan's Salamander Plethodon jordani Jordan's salamander carries genuinely unpalatable skin secretions, a real defence convincing enough that a harmless neighbouring species evolved to look just like it. Read the guide →
Mammals NT Juan Fernandez Fur Seal Arctocephalus philippii The Juan Fernandez fur seal was hunted so heavily that it was believed extinct for decades, until a small surviving colony was rediscovered in 1965 and slowly rebuilt into tens of thousands today. Read the guide →
Invertebrates NE Jumping Spider Salticidae Jumping spiders have the sharpest eyesight of any animal their size, hunt by stalking and pouncing like cats, use a silk safety line on every leap, and perform elaborate dances to court mates. Read the guide →
Amphibians NT Junaluska Salamander Eurycea junaluska The Junaluska salamander is so rarely encountered that its adult form went undescribed for years after its larvae were already known to science, a genuine reversal of how most species get discovered. Read the guide →
Invertebrates LC June Beetle Phyllophaga The June beetle's underground larvae feed on plant roots for up to three years before the clumsy, light-drawn adult ever emerges to bump noisily into porch screens. Read the guide →
Mammals LC Jungle Cat Felis chaus The jungle cat is a long-legged, plain-coated wild cat that thrives in reed beds and wetlands from Egypt to Southeast Asia, and was once mummified in ancient Egypt. Read the guide →
Birds EN Kagu Rhynochetos jubatus The kagu is a near-flightless grey forest bird found only in New Caledonia, with a loose crest, red legs, and "nasal corns" no other bird has. It barks at dawn like a dog and had no ground predators. Read the guide →
Amphibians VU Kaiser's Spotted Newt Neurergus kaiseri Kaiser's spotted newt is a black, white and orange salamander from a few mountain streams in western Iran, nearly bought to extinction by collectors through the online pet trade. Read the guide →
Birds VU Kaka Nestor meridionalis The kaka survives mainly on predator-free islands and sanctuaries today, a large, intelligent New Zealand forest parrot whose close relative the kea has fared better against introduced predators. Read the guide →
Birds CR Kakapo Strigops habroptilus The kākāpō is the world's only flightless parrot and the heaviest — a nocturnal, moss-scented New Zealand bird that booms for a mate and came within a few dozen individuals of extinction. Read the guide →
Birds LC Kakariki Cyanoramphus novaezelandiae The kakariki forages closer to the forest floor than most parakeets, supplementing seeds and fruit with insects and even the eggs of other birds when the opportunity arises. Read the guide →
Birds LC Kalij Pheasant Lophura leucomelanos The kalij pheasant is one of the most variable pheasant species alive, split into subspecies whose plumage ranges from glossy blue-black to pale brown across its Himalayan and South Asian range. Read the guide →
Invertebrates LC Katydid Tettigoniidae The katydid's leaf-shaped wings mimic real foliage down to fake vein patterns and chewed-looking edges, and its ears sit not on its head but on its front legs. Read the guide →
Birds EN Kea Nestor notabilis The kea is the world's only alpine parrot — an olive-green New Zealand bird known for tearing apart cars, solving puzzles in teams, and a "play" call that makes other kea act playful. Read the guide →
Birds LC Keel-billed Toucan Ramphastos sulfuratus The keel-billed toucan of Central America carries a huge rainbow bill that is nearly weightless, works as a radiator to shed body heat, and reaches fruit on twigs too thin to perch on. Read the guide →
Reptiles LC Keelback Rhabdophis tigrinus The keelback steals the very toxins from the toads it eats and stores them in glands on its own neck, a genuine case of a snake borrowing another animal's chemical defenses for its own protection. Read the guide →
Reptiles LC Keeled Earless Lizard Holbrookia propinqua The keeled earless lizard favors loose coastal sand dunes and barrier islands, its raised, ridged scales giving it a rougher texture than its smoother lesser earless lizard relative. Read the guide →
Birds LC Kelp Goose Chloephaga hybrida The kelp goose shows one of the most extreme examples of colour difference between the sexes in any waterfowl, with males almost entirely pure white and females a mottled dark grey and black. Read the guide →
Birds LC Kelp Gull Larus dominicanus The kelp gull is one of the most widespread gulls of the Southern Hemisphere, an adaptable scavenger observed pecking chunks of skin and blubber directly from living southern right whales. Read the guide →
Reptiles CR Kemp's Ridley Sea Turtle Lepidochelys kempii Kemp's ridley is the smallest and rarest sea turtle. Almost all its females nest on one Mexican beach, in daylight, in mass arrivals that crashed from an estimated 40,000 in a day to a few hundred. Read the guide →
Reptiles CR Kemp's Ridley Turtle Lepidochelys kempii The Kemp's ridley turtle is the smallest and rarest sea turtle, and nearly its entire population nests during a single synchronized mass event called an arribada on one stretch of Mexican beach. Read the guide →
Birds LC Kentucky Warbler Geothlypis formosa The Kentucky warbler spends nearly all its time walking on the forest floor rather than in the canopy, its bold black sideburns and spectacled face making it a striking ground-dwelling songbird. Read the guide →
Birds LC Kerguelen Petrel Lugensa brevirostris The Kerguelen petrel is a dark, fast-flying gadfly petrel known for extraordinarily erratic flight, veering and looping through the air in a way that makes it hard for predators to catch. Read the guide →
Amphibians VU Kern Canyon Slender Salamander Batrachoseps simatus The Kern Canyon slender salamander survives in a narrow band of canyon habitat barely a few kilometres wide, one of the most geographically restricted salamanders in North America. Read the guide →
Amphibians LC Kern Plateau Salamander Batrachoseps robustus The Kern Plateau salamander is a stockier, more robust member of a genus best known for extremely slender bodies, surviving at high elevation on one isolated plateau in the southern Sierra Nevada. Read the guide →
Amphibians LC Kiamichi Slimy Salamander Plethodon kiamichi The Kiamichi slimy salamander is confined to one small mountain range in Oklahoma, one of more than a dozen genetically distinct species revealed when the old slimy salamander complex was split apart. Read the guide →
Mammals LC Kiang Equus kiang The kiang is the largest wild ass, a chestnut-coated grazer of the high Tibetan Plateau that gallops across open plains at altitudes of more than 4,000 metres. Read the guide →
Amphibians EW Kihansi Spray Toad Nectophrynoides asperginis The Kihansi spray toad lived only in the mist of one Tanzanian waterfall until a dam dried its home. Saved by a last-minute airlift to US zoos, it has since been bred and returned to the wild. Read the guide →
Birds LC Killdeer Charadrius vociferus The killdeer is a plover that lives far from any shore, on gravel lots, playing fields, and rooftops, and it protects its ground nest with a famous act, flopping away dragging a fake broken wing. Read the guide →
Fish LC Killifish Cyprinodontiformes A killifish is a small, often brilliantly coloured fish, and the annual species lay eggs that survive complete drying in mud for months, hatching into a new generation after the adults have died. Read the guide →
Reptiles VU King Cobra Ophiophagus hannah The king cobra is the world's longest venomous snake and the only one that builds a nest for its eggs. Learn how it hunts other snakes, why it rears up, and what its venom does. Read the guide →
Birds LC King Penguin Aptenodytes patagonicus The king penguin is the second-largest penguin, with the longest breeding cycle of any bird — over a year per chick. Learn how its brown, woolly-looking chicks survive a sub-Antarctic winter. Read the guide →
Birds NT King Rail Rallus elegans The king rail is the largest rail species in North America, a freshwater marsh specialist whose numbers have quietly declined for decades as the wetlands it depends on continue to disappear. Read the guide →
Invertebrates NE King Scallop Pecten maximus The king scallop is a large, fan-shaped bivalve of north-eastern Atlantic sand and gravel that rests on a flat lid, swims by clapping its shell, and watches the world through rows of blue eyes. Read the guide →
Birds VU King Shag Leucocarbo carunculatus The king shag is one of the rarest shag species on Earth, breeding only within a single sheltered sound in New Zealand and never dispersing far from that one small stretch of coastline. Read the guide →
Birds LC King Vulture Sarcoramphus papa The king vulture is the world's most colourful vulture, its bare head painted orange, purple, red and yellow. Its bill is the strongest of any New World vulture, opening carcasses others cannot. Read the guide →
Birds NE Kingfisher Alcedinidae A kingfisher is a compact, big-headed, dagger-billed bird, most famous for the species that dive headfirst into water to catch fish, though many kingfishers live in dry forest and never fish at all. Read the guide →
Reptiles NE Kingsnake Lampropeltis A kingsnake is a non-venomous American constrictor that eats other snakes, rattlesnakes included, is largely immune to their venom, and in several species mimics the deadly coral snake. Read the guide →
Mammals LC Kinkajou Potos flavus The kinkajou is a golden, tree-dwelling raccoon relative with a fully prehensile tail, a 12 cm tongue for raiding flowers and bees' nests, and ankles that rotate so it can run headfirst down a trunk. Read the guide →
Birds NT Kirtland's Warbler Setophaga kirtlandii The Kirtland's warbler nests almost exclusively in young jack pine of a specific age, a habitat requirement so narrow that fire suppression once pushed the species to the edge of extinction. Read the guide →
Mammals LC Kit Fox Vulpes macrotis The kit fox is the smallest wild canid in North America, a delicate desert species with enormous ears that digs its own den, spending nearly every daylight hour hidden underground to escape the heat. Read the guide →
Fish VU Kitefin Shark Dalatias licha The kitefin shark is believed to be the largest known luminous vertebrate, its entire underside glowing pale blue-green to erase its silhouette from predators lurking in the darkness below. Read the guide →
Mammals VU Kitti's Hog-Nosed Bat Craseonycteris thonglongyai Kitti's hog-nosed bat is among the smallest mammals alive, roughly the size of a bumblebee, restricted to a handful of limestone caves in Thailand and Myanmar. Read the guide →
Birds VU Kiwi Apteryx A kiwi is a flightless, nocturnal New Zealand bird that behaves more like a mammal, with nostrils at the bill tip, hair-like feathers, burrows, and an egg up to a quarter of its body weight. Read the guide →
Mammals LC Klipspringer Oreotragus oreotragus The klipspringer walks on the very tips of its blunt, cylindrical hooves, a rock-climbing antelope that bounds across cliffs and boulders where few predators can follow. Read the guide →
Reptiles LC Knight Anole Anolis equestris The knight anole is the largest anole species found in the United States, a Cuban import capable of biting hard, eating smaller lizards, and even taking small birds from the treetops. Read the guide →
Reptiles LC Knob-Tailed Gecko Nephrurus The knob-tailed gecko stores fat reserves in a small round nub at the end of its tail instead of along its length, giving it one of the most distinctive silhouettes of any desert gecko. Read the guide →
Mammals VU Koala Phascolarctos cinereus The koala is a marsupial — not a bear — that eats only toxic eucalyptus leaves and sleeps up to 22 hours a day. Learn how it survives that diet and why it's now Endangered in eastern Australia. Read the guide →
Mammals LC Kob Kobus kob The kob relies on a unique mating system where males display and compete on tiny territories called leks, a reddish-brown floodplain antelope closely related to the waterbuck. Read the guide →
Mammals VU Kodkod Leopardus guigna The kodkod is the smallest wild cat in the Americas, hunting small birds and rodents through the dense temperate rainforest of Chile. Read the guide →
Birds LC Koklass Pheasant Pucrasia macrolopha The koklass pheasant wears a distinctive double-pointed crest unlike any other pheasant, and its harsh, far-carrying call gives the species its onomatopoeic common name. Read the guide →
Reptiles EN Komodo Dragon Varanus komodoensis The Komodo dragon is the largest lizard alive, a venomous ambush predator found on just a few Indonesian islands. Learn how it hunts prey many times its size and why it's now Endangered. Read the guide →
Birds NT Kori Bustard Ardeotis kori The kori bustard is the heaviest bird capable of flight, males up to 19 kg, needing a long running start to get airborne. Courting males inflate a huge white throat pouch to the ground. Read the guide →
Fish LC Kribensis Pelvicachromis pulcher The kribensis is a small, peaceful West African cichlid in which the female often outshines the male, flushing a vivid purple-red belly that is brightest exactly when she is ready to breed. Read the guide →
Invertebrates LC Krill Euphausiacea Krill are shrimp-like crustaceans that swarm in the billions at the core of the Southern Ocean food web, feeding whales, penguins, and seabirds — by weight among the most abundant animals alive. Read the guide →
Fish LC Kuhli Loach Pangio kuhlii The kuhli loach is a slender, eel-like bottom-dweller that squirms through gravel and leaf litter by day and only really becomes active once the aquarium lights go out. Read the guide →
Reptiles LC Labord's Chameleon Furcifer labordi Labord's chameleon has the shortest lifespan of any known four-legged vertebrate, hatching, maturing, breeding, and dying within a single year of life. Read the guide →
Reptiles LC Lace Monitor Varanus varius The lace monitor is one of Australia's largest and most recognised reptiles, a powerful climbing goanna known to raid campsites as readily as it hunts through native forest. Read the guide →
Invertebrates LC Lacewing Chrysopidae The lacewing looks delicate enough to tear at a touch, but its larvae are voracious predators nicknamed aphid lions, some disguising themselves under a pile of drained prey as camouflage. Read the guide →
Birds LC Ladder-backed Woodpecker Dryobates scalaris The ladder-backed woodpecker thrives in arid desert scrub where few other woodpeckers venture, nesting in cacti and mesquite across the southwestern United States and Mexico. Read the guide →
Birds LC Lady Amherst's Pheasant Chrysolophus amherstiae Lady Amherst's pheasant trails a tail banded in bold black and white stripes, a striking pattern that sets it apart even among its own famously colourful genus. Read the guide →
Invertebrates LC Ladybug Coccinella septempunctata The ladybug is a small, dome-shaped beetle whose bright spots warn that it tastes foul. Both the adult and its spiny larva eat aphids by the hundred, and farmers have valued them for centuries. Read the guide →
Fish LC Ladyfish Elops saurus The ladyfish is a close tarpon relative nicknamed the "poor man's tarpon" for its spectacular jumps and long runs, though its extremely bony flesh means almost nobody actually eats one. Read the guide →
Birds LC Lake Duck Oxyura vittata The lake duck is a small South American diving duck best known for an extraordinary biological record, a male reproductive organ far longer than its entire body. Read the guide →
Amphibians CR Lake Patzcuaro Salamander Ambystoma dumerilii The Lake Patzcuaro salamander is a gilled, permanently aquatic axolotl relative from one Mexican highland lake, kept from extinction partly by nuns who have bred it for generations. Read the guide →
Fish LC Lake Sturgeon Acipenser fulvescens The lake sturgeon is a bony-plated living fossil of North American lakes that can live past 100 years, was nearly wiped out for its caviar and isinglass, and is recovering only slowly. Read the guide →
Fish LC Lake Trout Salvelinus namaycush The lake trout retreats into the deepest, coldest water of a lake as the seasons warm, and some individuals in the coldest northern lakes have been documented living for over a century. Read the guide →
Fish LC Lake Whitefish Coregonus clupeaformis The lake whitefish spawns in the coldest months, releasing eggs over gravel shoals just as winter ice begins to form, a historically vital Great Lakes commercial fish built around cold-water timing. Read the guide →
Fish NE Lamprey Petromyzontiformes A lamprey is a jawless fish with a round rasping sucker for a mouth, one of only two surviving lines of the earliest vertebrates; its larvae spend years buried blind in river mud. Read the guide →
Invertebrates LC Lancelet Branchiostoma A lancelet is a thin, translucent, blade-shaped sea creature with a stiff rod down its back, a simple body plan echoing the earliest stage every backboned animal embryo passes through. Read the guide →
Fish LC Lanternfish Myctophidae Lanternfish are small, bioluminescent deep-sea fish so numerous they may make up the majority of all fish biomass in the ocean, and their nightly rise to the surface is the largest migration on Earth. Read the guide →
Fish LC Lanternshark Etmopterus spinax The lanternshark glows from rows of light-producing organs along its belly, using counter-illumination to erase its own silhouette from predators lurking in the darkness below. Read the guide →
Birds LC Lapland Longspur Calcarius lapponicus The Lapland longspur breeds across the Arctic tundra in staggering numbers, then gathers into enormous winter flocks on open farmland, sometimes numbering in the tens of thousands at a single site. Read the guide →
Amphibians VU Larch Mountain Salamander Plethodon larselli The Larch Mountain salamander survives within talus slopes scattered across the Columbia River Gorge, so tied to volcanic rock rubble that suitable habitat can end within a few metres. Read the guide →
Invertebrates EN Large Blue Phengaris arion The large blue is an Endangered butterfly whose caterpillar tricks red ants into carrying it into their nest, where it eats their grubs, and it was reintroduced to Britain after going extinct there. Read the guide →
Mammals NT Large Flying Fox Pteropus vampyrus The large flying fox is one of the biggest bats on Earth, wingspan up to 1.5 metres. It eats only fruit and nectar, sees well, uses no echolocation, and pollinates Southeast Asia's forests by night. Read the guide →
Mammals LC Large Hairy Armadillo Chaetophractus villosus The large hairy armadillo digs extensive burrows across the Patagonian steppe, its body covered in long hair growing between armoured plates unlike most other armadillo species. Read the guide →
Invertebrates LC Large Red Damselfly Pyrrhosoma nymphula The large red damselfly is the first damselfly of spring, a slender red-and-black insect that emerges in April and May around ponds, ditches, and slow streams. Read the guide →
Fish LC Largemouth Bass Micropterus salmoides The largemouth bass is North America's most popular freshwater game fish, an ambush predator of weedy lakes and ponds that has been introduced to dozens of countries, where it often turns invasive. Read the guide →
Fish CR Largetooth Sawfish Pristis pristis The largetooth sawfish is a ray with a chainsaw for a nose — a toothed blade it swings sideways to stun fish and sense their heartbeats. Once in 90 countries, it is now Critically Endangered. Read the guide →
Birds LC Lark Alaudidae A lark is a ground-nesting, streaky brown songbird best known for the skylark, which climbs almost invisibly high on fluttering wings and sings a long, continuous, unbroken song for minutes at a time. Read the guide →
Birds LC Lark Sparrow Chondestes grammacus The lark sparrow carries one of the boldest facial patterns of any North American sparrow, a striking harlequin arrangement of chestnut, black, and white that sets it apart from the streaky crowd. Read the guide →
Birds LC Laughing Gull Leucophaeus atricilla The laughing gull takes its name from a distinctive, cackling call that sounds remarkably like human laughter, a sound heard constantly along beaches and boardwalks across the Americas. Read the guide →
Birds LC Laughing Kookaburra Dacelo novaeguineae The laughing kookaburra is the world's largest kingfisher, but it hunts snakes, lizards, and mice on land rather than fish. Its cackling dawn chorus marks the family's territory. Read the guide →
Birds NT Laysan Albatross Phoebastria immutabilis The Laysan albatross includes the world's oldest known wild bird, a female named Wisdom who has continued returning to the same colony to breed for more than seven decades. Read the guide →
Mammals CR Leadbeater's Possum Gymnobelideus leadbeateri Leadbeater's possum was presumed extinct for decades until its rediscovery in 1961, and remains critically endangered in the mountain ash forests it depends on. Read the guide →
Invertebrates NE Leaf Insect Phyllium giganteum The leaf insect looks so exactly like a leaf it even has fake veins and ragged bite-mark edges. It sways gently as it walks to mimic a leaf drifting in the breeze. Read the guide →
Invertebrates NE Leaf Sheep Nudibranch Costasiella kuroshimae The leaf sheep is a tiny sea slug that eats algae, keeps the algae's chloroplasts alive inside its own body, and then runs on the sugars they photosynthesise — a part-time solar-powered animal. Read the guide →
Invertebrates LC Leaf-Footed Bug Coreidae The leaf-footed bug carries flattened, leaf-shaped expansions on its hind legs, oversized ornaments some males use to wrestle rivals for territory. Read the guide →
Reptiles LC Leaf-nosed Snake Phyllorhynchus A leaf-nosed snake is a small, nocturnal desert burrower named for an enlarged, upturned scale on the tip of its snout that it uses like a tiny shovel to push through loose sand. Read the guide →
Reptiles LC Leaf-tailed Gecko Uroplatus phantasticus The satanic leaf-tailed gecko is a Madagascar lizard that mimics a curled dead leaf — fake veins, notched edges, "damage" holes and all. It has one of the most complete camouflages in nature. Read the guide →
Reptiles LC Leaf-Toed Gecko Phyllodactylus nocticolus The leaf-toed gecko is one of the few geckos native to the desert rock outcrops of the southwestern United States, clinging to vertical surfaces with distinctive leaf-shaped pads on each toe. Read the guide →
Invertebrates LC Leafcutter Ant Atta cephalotes Leafcutter ants do not eat the leaves they carry — they farm a fungus with them. A single colony can contain 8 million ants, move tonnes of soil, and consume as much vegetation as a cow. Read the guide →
Invertebrates LC Leafhopper Cicadellidae The leafhopper communicates through vibrations sent directly through plant stems, a private conversation happening constantly on leaves all around us that human ears simply cannot detect. Read the guide →
Fish LC Leafy Seadragon Phycodurus eques The leafy seadragon is a relative of the seahorse covered in leaf-shaped skin flaps that make it vanish into drifting seaweed. It cannot curl its tail, and the male carries the eggs. Read the guide →
Mammals LC Least Chipmunk Tamias minimus The least chipmunk is the smallest chipmunk species in North America, a fast forager at home in dense forest understory and open, rocky mountain slopes across a huge stretch of the continent. Read the guide →
Fish LC Least Darter Etheostoma microperca The least darter ranks among the smallest freshwater fish in North America, small enough that its entire life plays out within a single quiet, weedy pool most anglers would never think to look in. Read the guide →
Birds LC Least Flycatcher Empidonax minimus The least flycatcher is the smallest of a notoriously difficult group of nearly identical flycatchers, told apart from its relatives mainly by its sharp, emphatic "che-bek" call rather than looks. Read the guide →
Fish LC Least Killifish Heterandria formosa The least killifish is one of the smallest freshwater fish in North America, and despite its tiny size it gives birth to live young a couple at a time over an extended period rather than all at once. Read the guide →
Mammals LC Least Shrew Cryptotis parva The least shrew is the smallest shrew species in North America, and unlike most solitary, aggressive shrews it huddles together with others in shared nests for warmth. Read the guide →
Invertebrates LC Least Skipper Ancyloxypha numitor The least skipper flies with a weak, bobbing flutter low over grass, a flight style so different from most other skippers' fast, darting flight that it helps identify the species from a distance. Read the guide →
Birds NT Least Tern Sternula antillarum The least tern is the smallest tern in North America, nesting in fragile colonies directly on open sand where males court females by offering them a freshly caught fish. Read the guide →
Mammals LC Least Weasel Mustela nivalis The least weasel is the smallest meat-eating mammal in the world, a thumb-thin predator that can chase a mouse down its own burrow but must eat a third of its body weight a day to stay alive. Read the guide →
Reptiles VU Leatherback Sea Turtle Dermochelys coriacea The leatherback is the largest turtle on Earth and the deepest-diving reptile — a jellyfish hunter that keeps its body warm in near-freezing seas and crosses whole oceans to nest. Read the guide →
Mammals NT Lechwe Kobus leche The lechwe has water-repellent, oily fur and elongated hooves built for splashing through shallow floodplains at speed, often forming herds tens of thousands strong. Read the guide →
Invertebrates LC Leech Hirudinea A leech is a segmented worm with a sucker at each end that can drink several times its own body weight in blood in a single meal, using an anaesthetic in its saliva so the host never feels the bite. Read the guide →
Reptiles LC Legless Lizard Multiple lizard families A legless lizard is any of many lizards that have independently lost their legs and look like snakes, but keep eyelids, ear openings, and a long shed-off tail, and most burrow or live in dense grass. Read the guide →
Mammals LC Leisler's Bat Nyctalus leisleri Leisler's bat, or the lesser noctule, is a high, fast-flying tree bat of Europe that is rare in Britain but common in Ireland, where it is one of the country's most numerous bats. Read the guide →
Fish VU Lemon Shark Negaprion brevirostris The lemon shark's yellowish skin blends so well with sandy shallows that researchers have used it for decades to study social behavior most sharks never get credited with. Read the guide →
Fish LC Lemonpeel Angelfish Centropyge flavissima The lemonpeel angelfish glows solid yellow with a bright blue ring around each eye, a small dwarf angelfish that grazes algae and slips into reef crevices when threatened. Read the guide →
Mammals EN Lemur Lemuroidea A lemur is a primate found wild only on Madagascar, where the group split into about 100 species from mouse-sized to the dog-sized indri, and it is the most endangered group of mammals on Earth. Read the guide →
Mammals VU Leopard Panthera pardus The leopard is the most adaptable big cat — a solitary, night-hunting climber that hauls its kills into trees. Learn how it survives almost anywhere and why it's still Vulnerable. Read the guide →
Mammals LC Leopard Cat Prionailurus bengalensis The leopard cat is a small, spotted wild cat found across much of Asia, adaptable enough to live in plantations, and the wild ancestor of the domestic Bengal cat breed. Read the guide →
Amphibians LC Leopard Frog Lithobates pipiens and relatives A leopard frog is a slim green or brown North American frog scattered with dark halo-ringed spots, once so common that it was collected by the million for dissection classes and is now in decline. Read the guide →
Reptiles LC Leopard Gecko Eublepharis macularius The leopard gecko is a ground-dwelling desert lizard with movable eyelids, a fat storage tail it can drop and regrow, and a calm nature that made it one of the first domesticated reptiles. Read the guide →
Reptiles LC Leopard Lizard Gambelia The leopard lizard is fast and bold enough to chase down and eat other lizards, a spotted desert predator that runs on its hind legs alone when it really needs to close the distance quickly. Read the guide →
Invertebrates DD Leopard Sea Cucumber Bohadschia argus The leopard sea cucumber ejects sticky, toxic threads from its own body cavity when threatened, a spotted reef grazer whose defensive strategy involves discharging part of its own internal organs. Read the guide →
Mammals LC Leopard Seal Hydrurga leptonyx The leopard seal is Antarctica's top seal predator — a huge, reptilian-headed hunter that kills penguins and other seals but also filters krill through its teeth. Learn how this loner lives. Read the guide →
Reptiles LC Leopard Snake Zamenis situla The leopard snake is a small, secretive constrictor of southeastern Europe, patterned with red-brown, black-edged blotches on a pale background, and one of the continent's most beautiful snakes. Read the guide →
Reptiles LC Leopard Tortoise Stigmochelys pardalis The leopard tortoise is Africa's largest savanna tortoise and the fourth-largest tortoise species, a boldly patterned grazer that, unusually for a tortoise, can swim and does not dig its own burrow. Read the guide →
Fish LC Leopard Wrasse Macropharyngodon The leopard wrasse carries bold, spotted patterning reminiscent of a leopard's coat, and buries itself in sand each night or whenever danger threatens. Read the guide →
Reptiles CR Lesser Antillean Iguana Iguana delicatissima The Lesser Antillean iguana is a Caribbean island iguana in steep decline because it breeds with the invasive green iguana, which is displacing it across the Lesser Antilles. Read the guide →
Birds LC Lesser Black-backed Gull Larus fuscus The lesser black-backed gull looks much like a herring gull with a darker back and yellow legs, and has increasingly abandoned long migrations to winter closer to home. Read the guide →
Reptiles LC Lesser Earless Lizard Holbrookia maculata The lesser earless lizard has no visible ear opening at all, an adaptation that keeps sand out while it dives and wriggles beneath loose soil to escape both predators and the desert heat. Read the guide →
Birds LC Lesser Greenlet Pachysylvia decurtata The lesser greenlet is a small, plain greenish-yellow vireo-family bird that forages methodically through Neotropical forest canopy and understory for insects. Read the guide →
Mammals LC Lesser Grison Galictis cuja The lesser grison hunts small vertebrates across a huge range of South American habitat, its masked grey-and-black face pattern making it one of the more distinctive mustelids on the continent. Read the guide →
Mammals LC Lesser Hedgehog Tenrec Echinops telfairi The lesser hedgehog tenrec independently evolved a spiny, ball-rolling body plan nearly identical to a true hedgehog's, despite belonging to an entirely unrelated family found only in Madagascar. Read the guide →
Mammals LC Lesser Horseshoe Bat Rhinolophus hipposideros The lesser horseshoe bat is Europe's smallest horseshoe bat, a plum-sized insect hunter that wraps itself in its wings to roost and calls through a horseshoe-shaped nose-leaf. Read the guide →
Mammals NT Lesser Kudu Tragelaphus imberbis The lesser kudu is a smaller, more vividly striped relative of the greater kudu, an extremely shy dry-bushland antelope that freezes and vanishes into cover at the faintest disturbance. Read the guide →
Mammals LC Lesser Long-Nosed Bat Leptonycteris yerbabuenae The lesser long-nosed bat migrates seasonally between Mexico and the southwestern United States, pollinating agave and cactus flowers along a nectar-rich corridor. Read the guide →
Fish LC Lesser Sand Eel Ammodytes tobianus The lesser sand eel is a slim, silvery, burrowing fish of European sandy shores that shoals in vast numbers, dives into the sand to hide, and is vital food for puffins, terns, seals, and larger fish. Read the guide →
Amphibians LC Lesser Siren Siren intermedia The lesser siren is an eel-like aquatic salamander that keeps its feathery gills for life and has only tiny front legs. It survives drought by sealing itself in a mucus cocoon in the mud for months. Read the guide →
Fish LC Lesser Weever Echiichthys vipera The lesser weever is a small, sand-burying fish of European shores whose venomous black dorsal spines give a painful sting to bathers and paddlers who tread on it at low tide. Read the guide →
Invertebrates NE Lettuce Sea Slug Elysia crispata The lettuce sea slug steals functioning chloroplasts from algae it eats and keeps them alive in its own tissue, turning sunlight into energy the way a plant would, a genuine solar-powered animal. Read the guide →
Birds LC Lewis's Woodpecker Melanerpes lewis Lewis's woodpecker catches insects on the wing like a flycatcher rather than drilling into bark, paired with dark, iridescent plumage unlike any other woodpecker. Read the guide →
Mammals VU Liberian Mongoose Liberiictis kuhni The Liberian mongoose survives only in a small pocket of West African rainforest, one of the rarest and least-studied mongoose species, made harder to research by decades of regional instability. Read the guide →
Fish VU Licorice Gourami Parosphromenus deissneri The licorice gourami is a tiny, intensely coloured labyrinth fish restricted to disappearing peat-swamp pools, among the most threatened and least widely kept fish in the aquarium hobby. Read the guide →
Birds NT Light-mantled Albatross Phoebetria palpebrata The light-mantled albatross has a pale grey back contrasting with its dark body, a close relative of the sooty albatross that breeds further south and shares the same graceful courtship flight. Read the guide →
Birds LC Lilac-breasted Roller Coracias caudatus The lilac-breasted roller is a lilac, teal and blue African bird that hunts from an exposed perch, and gets its name from the male's tumbling, side-rolling courtship dive. Read the guide →
Invertebrates NE Lily Beetle Lilioceris lilii The lily beetle is a bright scarlet beetle that squeaks when handled and plays dead by dropping to land on its black underside, whose slimy grubs disguise themselves in their own droppings. Read the guide →
Amphibians VU Limestone Salamander Hydromantes brunus The limestone salamander survives within one small limestone outcrop area in California's Sierra Nevada foothills, among the most geographically restricted amphibians in North America. Read the guide →
Invertebrates LC Limpet Patellogastropoda A limpet grazes algae off intertidal rock at high tide, then returns to the exact same worn spot every time, a homing habit precise enough to wear a matching groove into the stone. Read the guide →
Birds LC Limpkin Aramus guarauna The limpkin is a brown wading bird of American marshes that eats almost nothing but apple snails, extracting them without breaking the shell. Its wailing scream has spooked people for centuries. Read the guide →
Fish LC Ling Molva molva The ling is a long, slender, eel-like member of the cod family that haunts deep reefs and wrecks of the north-eastern Atlantic, grows well over a metre long, and produces millions of eggs. Read the guide →
Fish LC Lingcod Ophiodon elongatus The lingcod is a large, aggressive Pacific predator with a mouth full of formidable teeth, and some individuals carry a harmless natural pigment that tints their raw flesh a startling blue-green. Read the guide →
Mammals VU Lion Panthera leo The lion is the only big cat that lives in social groups. Learn how prides hunt, how cubs are raised, and why lion numbers have fallen by roughly half since 1990. Read the guide →
Mammals EN Lion-Tailed Macaque Macaca silenus The lion-tailed macaque carries a dramatic silver-white mane and a tufted tail, one of the rarest and most endangered macaque species in the world. Read the guide →
Invertebrates NE Lion's Mane Jellyfish Cyanea capillata The lion's mane is the largest jellyfish in the world — one specimen had a 2-metre bell and tentacles trailing 37 metres. It drifts the cold northern seas eating plankton and fish. Read the guide →
Fish LC Lionfish Pterois A lionfish is a slow, showy, venomous-spined reef fish native to the Indo-Pacific that became one of the most destructive marine invaders on Earth after release into the Atlantic and Caribbean. Read the guide →
Birds LC Little Blue Heron Egretta caerulea The little blue heron hatches entirely white and only gradually turns its adult slate-blue colour, passing through an unusual patchy blue-and-white phase along the way. Read the guide →
Mammals EN Little Brown Bat Myotis lucifugus The little brown bat can catch hundreds of insects in a single hour using echolocation alone, a once-abundant species now devastated across much of its range by white-nose syndrome. Read the guide →
Birds LC Little Crake Zapornia parva The little crake is one of the smallest members of the entire rail family, a diminutive marsh bird that slips through reed beds so quietly its presence often goes entirely unnoticed. Read the guide →
Amphibians EN Little Devil Poison Frog Oophaga sylvatica The little devil poison frog carries colours so variable that nearby populations can look like different species, a small, toxic Amazonian frog whose diet fuels its own poison. Read the guide →
Birds LC Little Egret Egretta garzetta The little egret is the Old World counterpart to the snowy egret, sharing the same black legs and bright yellow feet used to stir up hidden prey in shallow water. Read the guide →
Amphibians LC Little Grass Frog Pseudacris ocularis The little grass frog is the smallest frog in North America, under 2 cm long, a tan wetland-edge chorus frog whose thin tinkling call is often mistaken for an insect. Read the guide →
Birds LC Little Penguin Eudyptula minor The little penguin is the smallest penguin species in the world, standing barely a foot tall, and comes ashore only after dark in a nightly shuffle known as the penguin parade. Read the guide →
Mammals LC Little Red Flying Fox Pteropus scapulatus The little red flying fox is Australia's most nomadic bat, tracking eucalypt flowering across enormous distances in colonies that can number in the hundreds of thousands. Read the guide →
Mammals CR Livingstone's Fruit Bat Pteropus livingstonii Livingstone's fruit bat is a Critically Endangered flying fox found only on two Comoro Islands, a large, fruit-eating bat that is unusually active in daylight. Read the guide →
Reptiles NE Lizard Lacertilia A lizard is a scaled reptile, the most species-rich group of reptiles, ranging from the 2 cm dwarf gecko to the 3 m Komodo dragon, and many can shed their tail to escape a predator. Read the guide →
Amphibians CR Loa Water Frog Telmatobius dankoi The Loa water frog survives in a single isolated stretch of river within Chile's Atacama Desert, making it one of the rarest and most narrowly distributed amphibians on Earth. Read the guide →
Fish LC Loach Cobitidae and Botiidae A loach is a slender, whiskered bottom-dwelling fish found across Eurasia and Southeast Asia, and one kind, the weather loach, is so sensitive to air pressure that it grows restless before a storm. Read the guide →
Invertebrates NE Lobster Nephropidae and Palinuridae A lobster is a large armoured sea-floor crustacean, and the clawed lobsters keep growing and moulting for life with no clear signs of ageing, so a big one may be over a century old. Read the guide →
Reptiles LC Loggerhead Musk Turtle Sternotherus minor The loggerhead musk turtle carries an oversized head relative to its small shell, giving it a genuinely painful bite for such a small turtle and a look distinct from its musk turtle relatives. Read the guide →
Reptiles VU Loggerhead Sea Turtle Caretta caretta The loggerhead is the world's most abundant sea turtle, a big-headed shellfish-crusher that navigates whole ocean basins using the Earth's magnetic field as a map to return to its home beach. Read the guide →
Birds NT Loggerhead Shrike Lanius ludovicianus The loggerhead shrike impales prey on thorns and barbed wire, a grim habit that earned it the nickname butcher bird and helps it tear apart food with a songbird's feet, not a raptor's talons. Read the guide →
Fish LC Logperch Percina caprodes The logperch flips over small rocks with its snout to expose hidden prey underneath, a distinctive feeding technique that sets this darter apart from most other small freshwater fish. Read the guide →
Birds LC Long-Billed Curlew Numenius americanus The long-billed curlew carries the longest bill of any North American shorebird, curved downward to reach deep into burrows that would leave any straight-billed relative empty-handed. Read the guide →
Mammals LC Long-eared Hedgehog Hemiechinus auritus The long-eared hedgehog carries ears disproportionately large even for a hedgehog, radiating heat away in the desert and steppe habitat it calls home. Read the guide →
Mammals LC Long-eared Jerboa Euchoreutes naso The long-eared jerboa is a tiny Gobi Desert rodent with ears a third longer than its head, the largest ear-to-body ratio of any mammal. It hops on long hind legs and catches insects in mid-leap. Read the guide →
Birds LC Long-Eared Owl Asio otus The long-eared owl roosts in groups of a dozen or more through winter, and when alarmed it stretches its body tall and thin, transforming into what looks like a broken branch. Read the guide →
Mammals LC Long-Nosed Bandicoot Perameles nasuta The long-nosed bandicoot uses its pointed snout to sniff out insects and fungi buried in soil, leaving distinctive small digging pits scattered across suburban gardens. Read the guide →
Mammals LC Long-Nosed Mongoose Xenogale naso The long-nosed mongoose has an unusually elongated snout and a partly aquatic lifestyle, a poorly studied Central African rainforest species that forages along streams and swampy ground. Read the guide →
Mammals NT Long-Nosed Potoroo Potorous tridactylus The long-nosed potoroo digs up underground fungi as its primary food, spreading spores through its droppings in a partnership vital to the health of its forest. Read the guide →
Reptiles LC Long-nosed Snake Rhinocheilus lecontei The long-nosed snake uses an upturned, pointed snout to dig lizards and their eggs out of loose desert soil, and if seized it releases blood from its cloaca as a startling, messy defensive display. Read the guide →
Invertebrates DD Long-Spined Sea Urchin Diadema antillarum The long-spined sea urchin lost up to 98 percent of its Caribbean population to a mysterious 1983 die-off, and reefs across the region are still recovering from the algae that followed. Read the guide →
Reptiles LC Long-Tailed Brush Lizard Urosaurus graciosus The long-tailed brush lizard spends its entire life inside a single desert shrub, its tail stretching far longer than its body and its stillness doing most of the hiding. Read the guide →
Amphibians LC Long-tailed Salamander Eurycea longicauda The long-tailed salamander carries a tail making up nearly two-thirds of its total body length, patterned with a distinctive herringbone marking that helps set it apart from other salamanders. Read the guide →
Birds LC Long-tailed Sylph Aglaiocercus kingii The long-tailed sylph trails an iridescent blue-green forked tail often longer than its entire body, one of the most elegant hummingbirds in flight across Andean cloud forest. Read the guide →
Mammals LC Long-Tailed Weasel Neogale frenata The long-tailed weasel can kill prey many times its own body weight, a slender, fearless hunter whose long body lets it follow rodents directly into their own burrows. Read the guide →
Amphibians LC Long-toed Salamander Ambystoma macrodactylum The long-toed salamander is named for its elongated fourth toe, and survives a wider range of elevations than almost any other salamander in North America, some breeding under lake ice. Read the guide →
Fish LC Longear Sunfish Lepomis megalotis The longear sunfish is a palm-sized freshwater fish of clear American streams, its turquoise-and-orange body marked with wavy blue face lines and a long black ear flap edged in white. Read the guide →
Invertebrates LC Longhorn Beetle Cerambycidae The longhorn beetle's antennae can stretch several times the length of its own body, among the most exaggerated antennae of any insect family on Earth. Read the guide →
Fish LC Longhorn Cowfish Lactoria cornuta The longhorn cowfish is encased in a rigid box-shaped shell with horn-like spines above its eyes, like a tiny cartoon bull. It swims awkwardly since its armour cannot bend. Read the guide →
Fish LC Longnose Butterflyfish Forcipiger flavissimus The longnose butterflyfish uses an extremely elongated snout to pluck small invertebrates from crevices in coral and rock that most other reef fish cannot reach. Read the guide →
Fish LC Longnose Chimaera Harriotta raleighana The longnose chimaera has an extremely elongated, pointed snout and a long, whip-like tail, a deep-sea relative of sharks that lays egg cases on soft sediment far below the reach of sunlight. Read the guide →
Fish LC Longnose Dace Rhinichthys cataractae The longnose dace has a flattened head and overhanging snout built to hug the bottom of the fastest, most turbulent riffles, letting it feed exactly where most other small fish cannot. Read the guide →
Fish LC Longnose Gar Lepisosteus osseus The longnose gar looks almost unchanged from fish that swam alongside early dinosaurs, its narrow beak-like snout lined with needle-sharp teeth. Its scales are hard enough to have made arrowheads. Read the guide →
Fish LC Longnose Hawkfish Oxycirrhites typus The longnose hawkfish uses an elongated, needle-toothed snout to pluck small crustaceans from crevices, perching motionless on gorgonian sea fans in a bold red-and-white crosshatch pattern. Read the guide →
Fish LC Longnose Sucker Catostomus catostomus The longnose sucker tolerates colder water than almost any other sucker in North America, found as far north as the Arctic Circle and surviving beneath ice through the harshest winters. Read the guide →
Birds LC Loon Gavia A loon is a diving waterbird of northern lakes, a fish hunter with solid bones and legs set so far back that it can barely walk, and its wailing calls are an emblem of the wilderness. Read the guide →
Invertebrates CR Lord Howe Island Stick Insect Dryococelus australis The Lord Howe Island stick insect, a hand-sized flightless tree lobster, was wiped out by ship rats and thought extinct until 24 were found clinging to a lone shrub on a sea stack in 2001. Read the guide →
Birds VU Lord Howe Woodhen Hypotaenidia sylvestris The Lord Howe woodhen recovered from as few as thirty individuals to a stable population through one of conservation's earliest successful island predator-eradication and captive-breeding programs. Read the guide →
Reptiles VU Louisiana Pine Snake Pituophis ruthveni The Louisiana pine snake lays unusually large eggs for its body size, and its survival is tied directly to pocket gophers, since it lives almost entirely inside their burrow systems. Read the guide →
Birds LC Louisiana Waterthrush Parkesia motacilla The Louisiana waterthrush is one of the most reliable indicators of a healthy forest stream, since it depends so heavily on clean, fast-flowing water that its presence alone signals good conditions. Read the guide →
Amphibians LC Lowland Burrowing Treefrog Smilisca fodiens The lowland burrowing treefrog spends most of the year underground in a moisture-sealing cocoon, emerging only after summer monsoon rains to breed in temporary desert pools before disappearing again. Read the guide →
Reptiles LC Lowland Copperhead Austrelaps superbus The lowland copperhead is a shy, cold-tolerant Australian snake of southern swamps and grassland with coppery flanks, no relation to the American copperhead, that gives birth to live young. Read the guide →
Amphibians VU Lowland Leopard Frog Lithobates yavapaiensis The lowland leopard frog survives in desert streams and springs of the arid Southwest, an unusually dry range for a leopard frog, and has declined sharply from introduced predators and disease. Read the guide →
Mammals LC Lowland Paca Cuniculus paca The lowland paca uses hollow chambers in its skull to amplify alarm calls into a booming, resonant sound far louder than its stocky, spotted body would suggest. Read the guide →
Mammals LC Lowland Streaked Tenrec Hemicentetes semispinosus The lowland streaked tenrec is a spiny black-and-yellow Madagascan mammal that rubs specialised quills together to make sound, one of the only mammals known to communicate this way. Read the guide →
Mammals VU Lowland Tapir Tapirus terrestris The lowland tapir is South America's largest land mammal — a browser with a short prehensile trunk and an ancient lineage barely changed in 20 million years, and the rainforest's chief seed-planter. Read the guide →
Birds LC Lucy's Warbler Leiothlypis luciae Lucy's warbler nests inside cavities and behind loose bark rather than in the open, one of only a small number of North American warblers to build a fully enclosed, hidden nest. Read the guide →
Invertebrates NE Lugworm Arenicola marina The lugworm is a plump, red-gilled burrowing worm of tidal sand flats whose coiled casts and dimples mark its U-shaped burrow, a food for wading birds and a favourite bait of anglers. Read the guide →
Fish NT Lumpfish Cyclopterus lumpus The lumpfish is a rotund, warty fish of the cold North Atlantic that clamps to rocks with a belly sucker, has its roe sold as budget caviar, and is farmed to pick sea lice off salmon. Read the guide →
Invertebrates NE Luna Moth Actias luna The luna moth emerges as an adult with no mouth at all, living about a week purely to mate before dying. Its pale green wings trail long tails that may help it dodge bat sonar. Read the guide →
Fish NE Lungfish Dipnoi A lungfish is a freshwater fish with true lungs that must breathe air to survive, and the African and South American species can seal themselves in a mud cocoon and wait out years of drought. Read the guide →
Amphibians NE Lungless Salamander Plethodontidae A lungless salamander has no lungs and breathes through its skin and mouth lining, a trade that ties it to cool damp forest but built the largest and most varied salamander family on Earth. Read the guide →
Reptiles LC Lyre Snake Trimorphodon spp. The lyre snake carries a distinctive V-shaped marking on its head, a mildly venomous rear-fanged specialist that spends much of its life navigating rock crevices in search of sleeping lizards. Read the guide →
Birds LC Lyrebird Menura A lyrebird is an Australian songbird with the most accurate vocal mimicry of any animal, copying other birds, chainsaws, and camera shutters while fanning a lyre-shaped tail over its head. Read the guide →
Fish LC Lyretail Anthias Pseudanthias squamipinnis The lyretail anthias carries a deeply forked, lyre-shaped tail fin, with peach-orange females and more vividly coloured males that compete to lead a shared harem. Read the guide →
Amphibians NT Mabee's Salamander Ambystoma mabeei Mabee's salamander survives in a narrow strip of the Atlantic coastal plain, breeding in temporary forest ponds that dry up completely for much of the year. Read the guide →
Mammals LC Macaque Macaca A macaque is an Old World monkey, the most widespread primate after humans, ranging from Japanese snow to Asian city streets, and the rhesus macaque is the standard laboratory primate. Read the guide →
Birds VU Macaroni Penguin Eudyptes chrysolophus The macaroni penguin carries a golden-yellow crest above each eye, and despite being one of the most numerous penguin species in the world, its population has fallen sharply in recent decades. Read the guide →
Fish NE Mackerel Scomber and relatives A mackerel is a small, fast relative of the tuna that swims in enormous schools, migrates along coasts with the seasons, and is one of the most heavily fished and most nutritious food fish. Read the guide →
Fish NT Mackerel Icefish Champsocephalus gunnari The mackerel icefish is a nearly transparent-blooded Antarctic fish, once heavily overfished, now managed under strict international quotas to help its population recover. Read the guide →
Birds LC Madagascar Buzzard Buteo brachypterus The Madagascar buzzard is the island's most widespread bird of prey, adapting to everything from dense rainforest to open farmland across nearly the entire country. Read the guide →
Reptiles LC Madagascar Day Gecko Phelsuma grandis The Madagascar day gecko is active by daylight rather than at night like most geckos, a vividly coloured exception that still licks its eyes clean with its tongue since it has no eyelids. Read the guide →
Reptiles LC Madagascar Day Gecko Phelsuma grandis and relatives The Madagascar day gecko is a brilliant green lizard active in full daylight, unusual for a gecko. It licks nectar from flowers and grips glass upside down through molecular attraction. Read the guide →
Birds CR Madagascar Fish Eagle Haliaeetus vociferoides The Madagascar fish eagle is one of the rarest raptors on Earth, with only a small number of breeding pairs left along the island's rivers, lakes, and coastline. Read the guide →
Reptiles VU Madagascar Ground Boa Acrantophis madagascariensis The Madagascar ground boa is one of the island's largest snakes, a heavy-bodied ambush predator that hunts on the forest floor rather than in the trees. Read the guide →
Invertebrates NE Madagascar Hissing Cockroach Gromphadorhina portentosa The Madagascar hissing cockroach forces air through its breathing holes to hiss like a snake — a rare insect sound made without wings or legs. It is wingless, palm-sized and gives live birth. Read the guide →
Birds LC Madagascar Magpie-robin Copsychus albospecularis The Madagascar magpie-robin is a glossy black-and-white songbird known for a rich, melodic song, with several distinct regional colour variations found across the island. Read the guide →
Birds LC Madagascar Paradise Flycatcher Terpsiphone mutata The Madagascar paradise flycatcher shows two distinct male colour forms and an exceptionally long, trailing central tail in breeding males that can be several times the length of the body. Read the guide →
Birds CR Madagascar Pochard Aythya innotata The Madagascar pochard was believed extinct for over a decade until a tiny population was rediscovered on a remote volcanic lake in 2006, making it one of the rarest birds on Earth. Read the guide →
Reptiles VU Madagascar Tree Boa Sanzinia madagascariensis The Madagascar tree boa spends most of its life coiled in rainforest branches, ambushing birds, bats, and small mammals, and is born bright orange before darkening with age. Read the guide →
Mammals EN Madame Berthe's Mouse Lemur Microcebus berthae Madame Berthe's mouse lemur is the smallest primate in the world, a mouse-sized nocturnal lemur found only in one small area of western Madagascar and listed as Endangered. Read the guide →
Fish NE Madtom Noturus spp. The madtom is among the very few catfish genera with a genuine venomous sting, delivered through grooved spines that make this small, secretive fish surprisingly painful to mishandle. Read the guide →
Birds LC Magellanic Diving-petrel Pelecanoides magellani The Magellanic diving-petrel breeds along the fjords and channels of southernmost South America, flying underwater with whirring wingbeats in pursuit of the small crustaceans it feeds on. Read the guide →
Birds LC Magellanic Horned Owl Bubo magellanicus The Magellanic horned owl is a smaller relative of the great horned owl, hunting across open Patagonian and Andean terrain rather than the forested habitat favoured by many large owls. Read the guide →
Reptiles LC Magellanic Lizard Liolaemus magellanicus The Magellanic lizard is the southernmost-ranging lizard species in the world, giving birth to live young rather than laying eggs to survive the cold of Tierra del Fuego. Read the guide →
Birds LC Magellanic Oystercatcher Haematopus leucopodus The Magellanic oystercatcher probes rocky and sandy shorelines for shellfish with a long, bright orange bill, its bold black-and-white plumage and pink legs standing out along Patagonian coasts. Read the guide →
Birds LC Magellanic Penguin Spheniscus magellanicus The Magellanic penguin migrates thousands of kilometres each year between its South American breeding colonies and wintering grounds, one of the longest migrations of any penguin species. Read the guide →
Birds LC Magellanic Plover Pluvianellus socialis The Magellanic plover is so taxonomically distinct that it is the only member of its own family, a small Patagonian wading bird that feeds its chicks by direct regurgitation. Read the guide →
Birds LC Magellanic Snipe Gallinago magellanica The Magellanic snipe probes deep into soft mud with a long, flexible bill, its cryptic plumage making it nearly invisible until it bursts into flight at the last moment. Read the guide →
Birds LC Magellanic Tapaculo Scytalopus magellanicus The Magellanic tapaculo breeds further south than almost any other tapaculo species, a tiny, dark, ground-hugging bird nearly impossible to see despite calling constantly from dense undergrowth. Read the guide →
Mammals LC Magellanic Tuco-tuco Ctenomys magellanicus The Magellanic tuco-tuco spends nearly its entire life underground in extensive burrow systems, its name echoing the repetitive call it uses to communicate below the Patagonian steppe. Read the guide →
Birds NT Magellanic Woodpecker Campephilus magellanicus The Magellanic woodpecker is the last thriving giant of its genus, a large, crested hunter of Patagonian forests whose closest relatives are extinct or possibly extinct. Read the guide →
Birds CR Magenta Petrel Pterodroma magentae The magenta petrel was believed extinct for over a century until a small breeding population was rediscovered in forested hills on the Chatham Islands, making it one of the rarest seabirds on Earth. Read the guide →
Birds LC Magnificent Frigatebird Fregata magnificens The magnificent frigatebird has the largest wing area for its weight of any bird, stays aloft for weeks without landing, and often feeds by bullying other seabirds into dropping their catch. Read the guide →
Birds LC Magnolia Warbler Setophaga magnolia The magnolia warbler was named after the tree it was first collected in during migration, even though it breeds almost entirely in young spruce and fir forest far from any magnolia. Read the guide →
Birds LC Magpie Pica A magpie is a bold black-and-white bird, and the Eurasian species is one of the smartest animals known, the first non-mammal to pass the mirror test, though several unrelated birds share the name. Read the guide →
Birds LC Magpie-Tanager Cissopis leverianus The magpie-tanager is unusually large and long-tailed for its family, its bold black-and-white pattern echoing a true magpie despite no close relation. Read the guide →
Fish LC Mahi-mahi Coryphaena hippurus The mahi-mahi is a fast, gaudy open-ocean fish that grows from egg to a metre long in under a year, lives only a few years, and blazes blue and gold in life before fading to grey as it dies. Read the guide →
Mammals EN Mahogany Glider Petaurus gracilis The mahogany glider was believed extinct for over a century before its rediscovery, a gliding marsupial now confined to one of the smallest and most threatened ranges of any Australian mammal. Read the guide →
Mammals CR Malabar Civet Viverra civettina The Malabar civet is feared possibly extinct in the wild, an Indian species with only a handful of confirmed sightings in recent decades as its Western Ghats forest home was converted to plantations. Read the guide →
Amphibians LC Malabar Gliding Frog Rhacophorus malabaricus The Malabar gliding frog is a bright green tree frog of India's Western Ghats that spreads four big webbed feet like parachutes to glide and steer between trees, and breeds in frothy foam nests. Read the guide →
Birds LC Malachite Kingfisher Corythornis cristatus The malachite kingfisher is one of Africa's most photographed birds, a tiny jewel-toned hunter with a vivid turquoise back and orange underparts that perches low over still water. Read the guide →
Amphibians CR Malagasy Rainbow Frog Scaphiophryne gottlebei The Malagasy rainbow frog is a tiny, brightly patterned burrowing frog found only in one canyon system in Madagascar. It climbs sheer rock with spade-tipped toes and inflates itself when threatened. Read the guide →
Amphibians LC Malayan Horned Frog Megophrys nasuta A Southeast Asian rainforest ambush predator whose brown, angular body and pointed eyelid and snout flaps hide it almost perfectly among the dead leaves of the forest floor. Read the guide →
Reptiles LC Malayan Pit Viper Calloselasma rhodostoma The Malayan pit viper is a leaf-litter ambusher of Southeast Asian forests and plantations with a brown-triangled pattern, whose venom causes serious bleeding and yielded the anticlotting drug ancrod. Read the guide →
Mammals EN Malayan Tapir Tapirus indicus The Malayan tapir is the largest tapir and the only Old World one, an Endangered Southeast Asian forest browser whose black-and-white coat breaks up its outline in the dark. Read the guide →
Birds LC Mallard Anas platyrhynchos The mallard is the most widespread duck on Earth and the ancestor of nearly every domestic breed. It dabbles for food, sleeps with half its brain awake, and hybridises freely. Read the guide →
Amphibians CR Mallorcan Midwife Toad Alytes muletensis The Mallorcan midwife toad was known only from fossils and presumed extinct for millions of years until a living population was discovered surviving in a remote mountain gorge on Mallorca in 1980. Read the guide →
Reptiles NE Mamba Dendroaspis A mamba is a fast, alert African elapid with fixed front fangs and rapid-acting neurotoxic venom; the black mamba is the longest venomous snake in Africa and among the quickest on land. Read the guide →
Birds LC Manakin Pipridae A manakin is a small tropical bird whose males perform some of the most elaborate courtship dances in the animal kingdom, including a rapid backward shuffle strikingly similar to the human moonwalk. Read the guide →
Birds LC Mandarin Duck Aix galericulata The mandarin duck is a small East Asian perching duck whose drake wears orange sail-feathers and a purple breast, nests in tree holes, and has become a naturalised bird of British parks. Read the guide →
Fish LC Mandarinfish Synchiropus splendidus The mandarinfish is one of only two animals known to make true blue pigment instead of faking it with light. It has no scales, a toxic mucus coat, and a dusk courtship rise into open water. Read the guide →
Mammals VU Mandrill Mandrillus sphinx The mandrill is the world's largest monkey and the most colourful mammal — a dominant male's scarlet-and-blue face and rump brighten with his rank. Its forests hold the biggest troops of any primate. Read the guide →
Mammals NT Maned Wolf Chrysocyon brachyurus The maned wolf is not a wolf or a fox but the tallest wild canid — a long-legged, red-coated animal of South American grassland whose diet is half fruit. Read the guide →
Reptiles LC Mangrove Monitor Varanus indicus The mangrove monitor swims confidently between islands across open saltwater, a semi-aquatic lizard equally at home diving after a fish as climbing a mangrove tree in search of eggs. Read the guide →
Reptiles LC Mangrove Snake Boiga dendrophila The mangrove snake wears bold yellow bands across a glossy black body, a mildly venomous rear-fanged hunter spending most of its life moving through branches above mangrove swamps. Read the guide →
Fish EN Manta Ray Mobula birostris The manta ray is the largest ray in the sea — a 7-metre, plankton-eating fish with the biggest brain of any fish and a curiosity about divers. Learn how it feeds, breeds, and why it is Endangered. Read the guide →
Amphibians EN Mantella Mantella A mantella is a tiny, vividly coloured frog found only in Madagascar that looks and behaves just like an unrelated South American poison frog, and most of its 16 or so species are threatened. Read the guide →
Invertebrates NE Mantis Mantodea A mantis is an ambush insect that holds its spined front legs folded as if praying, swivels its triangular head to look over its shoulder, and strikes at prey in about a fiftieth of a second. Read the guide →
Invertebrates NE Mantis Shrimp Stomatopoda A mantis shrimp is a reef crustacean whose strike is the fastest limb movement of any animal, hard enough to smash snail shells and crack aquarium glass, and it has the most complex eyes known. Read the guide →
Amphibians LC Many-Lined Salamander Stereochilus marginatus The many-lined salamander stays aquatic its entire life, never fully transforming into a land-dwelling adult, and can be found hiding among sphagnum moss in Carolina bay wetlands. Read the guide →
Reptiles LC Many-Lined Skink Plestiodon multivirgatus The many-lined skink carries an unusually high number of thin stripes running the length of its body, a pattern distinctive enough to give the species its own name. Read the guide →
Reptiles LC Map Turtle Graptemys A map turtle is a North American river turtle with fine contour-like lines across its shell, and females grow so much larger than males, with broader heads, that the sexes eat different food. Read the guide →
Birds LC Marabou Stork Leptoptilos crumenifer The marabou stork is a bald, hunched African scavenger with a wingspan near 3 metres. It follows vultures to carcasses, patrols rubbish dumps, and cools itself by defecating on its own legs. Read the guide →
Invertebrates NE Marble Gall Wasp Andricus kollari The marble gall wasp is a tiny Mediterranean wasp whose larvae force oak twigs to grow hard, round, marble-sized galls, and whose alternating generations were once exploited for making ink. Read the guide →
Mammals NT Marbled Cat Pardofelis marmorata The marbled cat is a house-cat-sized forest climber with a clouded-leopard-like coat and a tail nearly as long as its body, rarely seen anywhere in the forests of Southeast Asia. Read the guide →
Amphibians LC Marbled Newt Triturus marmoratus The marbled newt of France and Iberia is one of the largest and most striking European newts, bright green marbled with black, and where its range meets the great crested newt the two interbreed. Read the guide →
Mammals LC Marbled Polecat Vormela peregusna The marbled polecat arches its back and flashes a brightly patterned underside when threatened, a strikingly mottled Eurasian mustelid whose defensive display closely mirrors that of a skunk. Read the guide →
Fish VU Marbled Rockcod Notothenia rossii The marbled rockcod was the primary target of the earliest Southern Ocean commercial fishery, its South Georgia population collapsing by over 99 percent and still not recovered decades later. Read the guide →
Amphibians LC Marbled Salamander Ambystoma opacum The marbled salamander breeds on dry land in autumn, and the female curls around her eggs in a dry pool basin and guards them for weeks until the rains arrive and flood the nest. Read the guide →
Reptiles LC Marbled Whiptail Aspidoscelis marmorata The marbled whiptail thrives on some of the hottest, most sparsely vegetated desert flats in North America, staying active during the day when many other lizards have already retreated underground. Read the guide →
Invertebrates LC Marbled White Melanargia galathea The marbled white is a black-and-white chequered butterfly that is really a brown, a lover of flower-rich chalk grassland whose females scatter their eggs freely over the grass as they fly. Read the guide →
Mammals NT Margay Leopardus wiedii The margay can rotate its ankles nearly 180 degrees, letting it climb down trunks head-first and even hang from a single hind foot, an almost entirely arboreal wild cat built for life in the trees. Read the guide →
Fish LC Margined Madtom Noturus insignis The margined madtom carries a dark border along its fins that gives the species its name, and like its madtom relatives it delivers a mild but genuinely irritating sting if handled carelessly. Read the guide →
Fish NE Mariana Snailfish Pseudoliparis swirei The Mariana snailfish is the deepest-living fish known, caught more than 8,000 metres down in the Mariana Trench. It is a small, soft, translucent-pink animal that would fall apart at the surface. Read the guide →
Mammals EN Marianas Flying Fox Pteropus mariannus The Marianas flying fox, called fanihi in Chamorro, is an Endangered fruit bat of the Mariana Islands that is partly active by day and has been hit hard by hunting and habitat loss. Read the guide →
Fish LC Marine Angelfish Pomacanthidae The marine angelfish family includes dozens of tall, disc-shaped reef fish with a sharp spine on each gill cover, many of which change colour completely as they mature. Read the guide →
Fish LC Marine Betta Calloplesiops altivelis The marine betta hides its head in a crevice and fans its tail to display a false eye spot, impersonating the head of a moray eel to scare off would-be predators. Read the guide →
Invertebrates NE Marine Flatworm Polycladida The marine flatworm flashes warning colours vivid enough to be mistaken for a nudibranch, despite having no circulatory or respiratory system at all beneath that thin, flattened body. Read the guide →
Fish LC Marine Hatchetfish Sternoptychidae The marine hatchetfish has a body flattened into a thin silver blade and belly lights it tunes to match the daylight from above, erasing its shadow. Its tube-shaped eyes point permanently upward. Read the guide →
Reptiles VU Marine Iguana Amblyrhynchus cristatus The marine iguana of the Galápagos is the only lizard that forages in the sea, grazing algae off the seabed, sneezing out salt, and shrinking its own skeleton when food runs short. Read the guide →
Mammals EN Marine Otter Lontra felina The marine otter lives almost entirely in the sea, foraging along rocky Pacific coastlines rather than the rivers and lakes favoured by nearly all of its freshwater-dwelling relatives. Read the guide →
Mammals NT Markhor Capra falconeri The markhor is a large wild goat of Central Asia's mountains, males carrying corkscrew horns over 1.5 metres. Poached toward scarcity, it has recovered under community hunting schemes in Pakistan. Read the guide →
Invertebrates NE Marmalade Hoverfly Episyrphus balteatus The marmalade hoverfly is a small, orange-banded hoverfly whose larvae devour aphids, and whose adults migrate in their millions across the English Channel and other seas each year. Read the guide →
Birds CR Marquesan Kingfisher Todiramphus godeffroyi The Marquesan kingfisher survives on just a couple of remote French Polynesian islands, a Critically Endangered bird threatened by introduced rats that prey on its eggs and chicks. Read the guide →
Amphibians LC Marsh Frog Pelophylax ridibundus The marsh frog is the largest frog native to Europe, a big green water frog whose loud cackling chorus earns it the name laughing frog, and a parent species of the hybrid edible frog. Read the guide →
Mammals LC Marsh Mongoose Atilax paludinosus The marsh mongoose forages almost entirely along riverbanks and wetlands, an excellent swimmer despite lacking webbed feet, using dexterous paws to crack open crabs and mussels. Read the guide →
Amphibians LC Marsupial Frog Gastrotheca Female marsupial frogs carry their eggs in a pouch of skin on the back, nourished by a placenta-like membrane. In some species fully formed froglets hop straight out, skipping the tadpole stage. Read the guide →
Mammals DD Marsupial Mole Notoryctes typhlops The marsupial mole is a blind, earless, golden burrower of the Australian deserts that swims through loose sand, filling the tunnel behind it, and is one of the least-known mammals alive. Read the guide →
Birds EN Martial Eagle Polemaetus bellicosus The martial eagle is powerful enough to strike down prey many times its own body weight, Africa's largest eagle and one capable of killing animals as large as small antelope. Read the guide →
Birds LC Martin Progne and Delichon A martin is a large, dark swallow-family bird, and the purple martin of North America is now so tied to human-built birdhouses that almost the entire eastern population nests in nothing else. Read the guide →
Birds EN Marvelous Spatuletail Loddigesia mirabilis The male marvelous spatuletail has just four tail feathers, two of them bare wires ending in big blue discs he swings around his body in courtship. It lives only in one valley in northern Peru. Read the guide →
Reptiles EN Mary River Turtle Elusor macrurus The Mary River turtle lives in one Australian river, grows a mohawk of green algae, and can stay underwater for days by breathing through its cloaca. It was a common pet before science even named it. Read the guide →
Birds LC Masked Duck Nomonyx dominicus The masked duck is a small, secretive stiff-tailed duck that stays hidden in dense marsh vegetation, making it one of the least frequently seen ducks in the Americas. Read the guide →
Mammals LC Masked Shrew Sorex cinereus The masked shrew is the most widely distributed shrew species in North America, found from the Arctic tundra to temperate forest despite weighing barely more than a few paperclips. Read the guide →
Birds LC Masked Tityra Tityra semifasciata The masked tityra shows pale grey-white plumage set off by a black facial mask and bright red bare skin around the eyes, a conspicuous perching bird of Neotropical forest. Read the guide →
Birds LC Masked Trogon Trogon personatus The masked trogon lives at higher elevations than most of its relatives, males identified by a black mask surrounding the eyes against vivid green plumage. Read the guide →
Reptiles LC Massasauga Sistrurus catenatus The massasauga is a small, shy wetland rattlesnake of the North American interior with a buzz more like an insect than a rattle, and the eastern population is now federally threatened. Read the guide →
Reptiles LC Matamata Turtle Chelus fimbriata The matamata is a South American river turtle disguised as a heap of dead leaves. It never chews — it strikes its huge mouth open and vacuums a fish in whole in about 0.02 seconds. Read the guide →
Mammals EN Matschie's Tree Kangaroo Dendrolagus matschiei Matschie's tree kangaroo carries a bright reddish-gold coat through the cloud forests of a single New Guinea peninsula, descending from trees backward, tail-first, rather than head-first. Read the guide →
Mammals EN Mauritian Flying Fox Pteropus niger The Mauritian flying fox is an Endangered fruit bat found only on Mauritius, a key seed disperser of the island's forests that has been repeatedly culled as a threat to fruit crops. Read the guide →
Invertebrates NE Mauve Stinger Pelagia noctiluca The mauve stinger is a small, purple-pink, glow-in-the-dark jellyfish with a painful sting that drifts in vast swarms through the Mediterranean and eastern Atlantic and has no attached polyp stage. Read the guide →
Invertebrates LC Mayfly Ephemeroptera A mayfly spends up to two years underwater as a nymph and then, as a winged adult, may live for only a matter of hours, just long enough to mate and lay eggs before it dies. Read the guide →
Invertebrates LC Meadow Brown Maniola jurtina The meadow brown is one of the most common and widespread grassland butterflies of Europe, a modest brown butterfly with a single eyespot that flies even on dull days. Read the guide →
Invertebrates NE Meadow Grasshopper Pseudochorthippus parallelus The meadow grasshopper is a green or brown grassland grasshopper of Europe, whose short-winged females cannot fly and whose males sing by rubbing their hind legs against their wings. Read the guide →
Mammals LC Meadow Jumping Mouse Zapus hudsonius The meadow jumping mouse leaps on long hind legs with a tail longer than its body, and hibernates through most of the year in damp North American meadows. Read the guide →
Mammals LC Meadow Vole Microtus pennsylvanicus The meadow vole reproduces so quickly a single pair could theoretically produce over a million descendants a year, a foundational prey species whose boom-and-bust cycles ripple through the food web. Read the guide →
Birds LC Mealy Parrot Amazona farinosa The mealy parrot is one of the largest Amazona parrots, named for a dusty, mealy-looking whitish bloom that dusts its otherwise green plumage. Read the guide →
Fish NT Medaka Oryzias latipes The medaka was the first fish ever bred successfully in space, a small, hardy Japanese species that has become one of the most important model organisms in genetics research. Read the guide →
Fish LC Mediterranean Chromis Chromis chromis The Mediterranean chromis is a small, dark-brown damselfish that forms huge shoals above rocky reefs, whose juveniles are electric blue, and one of the most abundant fish in the Mediterranean. Read the guide →
Invertebrates NE Mediterranean Fanworm Sabella spallanzanii The Mediterranean fanworm is a large tube-dwelling worm whose spiral crown of feathery banded tentacles filters plankton and which has become a fouling invader in harbours far from home. Read the guide →
Reptiles LC Mediterranean Gecko Hemidactylus turcicus The Mediterranean gecko has hitchhiked in cargo shipments to warm cities across several continents, and now spends its nights clinging to porch lights, picking off insects drawn to the glow. Read the guide →
Mammals EN Mediterranean Monk Seal Monachus monachus The Mediterranean monk seal is one of the most endangered marine mammals on Earth, down to a few hundred left, now surviving mainly by giving birth inside hidden sea caves rather than on open beaches. Read the guide →
Mammals LC Meerkat Suricata suricatta The meerkat lives in tight cooperative gangs where members take turns standing guard, babysitting, and teaching pups to handle scorpions. Learn how a meerkat mob works and survives the Kalahari. Read the guide →
Fish LC Megamouth Shark Megachasma pelagios The megamouth shark was unknown to science until one was hauled up by a US Navy ship in 1976. It is one of only three filter-feeding sharks, a soft 5-metre giant with a huge mouth that may glow. Read the guide →
Fish CR Mekong Giant Catfish Pangasianodon gigas The Mekong giant catfish is one of the largest freshwater fish on Earth, reaching three metres and 300 kg, yet it is toothless and eats plants. Dams and overfishing have made it Critically Endangered. Read the guide →
Mammals LC Meller's Mongoose Rhynchogale melleri Meller's mongoose feeds almost entirely on termites, a poorly studied southern African species with noticeably fewer teeth than most of its insect-and-rodent-eating relatives. Read the guide →
Mammals LC Melon-Headed Whale Peponocephala electra The melon-headed whale travels in some of the largest groups of any dolphin, sometimes over a thousand individuals, a fast, deep-water species rarely seen close to shore except during strandings. Read the guide →
Birds LC Merlin Falco columbarius The merlin hunts small birds with a direct, relentless high-speed chase rather than the dramatic stoop favored by larger falcons, rarely giving its prey a second chance to escape. Read the guide →
Mammals LC Merriam's Kangaroo Rat Dipodomys merriami Merriam's kangaroo rat is one of the most widespread kangaroo rats of the American Southwest, a small hopping seed-eater that plugs its burrow by day and never needs to drink. Read the guide →
Reptiles LC Mexican Beaded Lizard Heloderma horridum The Mexican beaded lizard is one of few venomous lizards, larger and darker than the Gila monster. A hormone first found in its saliva became a major diabetes drug. Read the guide →
Amphibians LC Mexican Burrowing Toad Rhinophrynus dorsalis The Mexican burrowing toad is the only living member of a frog family over 100 million years old. It lives underground, calls like a moaning whoopee cushion, and fires its tongue forward at ants. Read the guide →
Amphibians LC Mexican Caecilian Dermophis mexicanus The Mexican caecilian is a limbless, burrowing amphibian that feeds its young inside its body for months, then gives birth. The unborn scrape a rich lining off the oviduct with baby teeth. Read the guide →
Mammals LC Mexican Free-tailed Bat Tadarida brasiliensis The Mexican free-tailed bat forms the largest colonies of any mammal, filling caves like Bracken Cave by the million, and it is the fastest animal in level flight at over 160 km/h. Read the guide →
Reptiles VU Mexican Garter Snake Thamnophis eques The Mexican garter snake declined so sharply in Arizona from habitat loss and invasive fish and bullfrogs that it is now federally listed as threatened in the very state where it was once common. Read the guide →
Reptiles LC Mexican Hognose Snake Heterodon kennerlyi The Mexican hognose snake performs the same death-feigning display as its relatives, flipping onto its back with its mouth hanging open, yet was only recognised as a distinct species recently. Read the guide →
Reptiles LC Mexican Mole Lizard Bipes biporus The Mexican mole lizard looks like a pink earthworm that sprouted a pair of tiny clawed front legs behind its head, and nothing else. It digs into desert soil and lives almost entirely underground. Read the guide →
Mammals EN Mexican Prairie Dog Cynomys mexicanus The Mexican prairie dog is an Endangered close relative of the black-tailed prairie dog, confined to a small area of high grassland in northeastern Mexico. Read the guide →
Invertebrates NT Mexican Redknee Tarantula Brachypelma hamorii The Mexican redknee tarantula defends itself by kicking barbed, itchy hairs off its abdomen rather than biting, a docile, long-lived spider now among the world's most popular pets. Read the guide →
Amphibians LC Mexican Spadefoot Spea multiplicata The Mexican spadefoot spends nearly its whole life buried underground, emerging only after the kind of heavy summer rain that turns a dry desert wash into a breeding pool for just a few critical days. Read the guide →
Fish LC Midas Blenny Ecsenius midas The Midas blenny swims openly among schools of orange anthias, mimicking their colour and movement closely enough to slip unnoticed through the reef. Read the guide →
Birds LC Middle Spotted Woodpecker Dendrocoptes medius The middle spotted woodpecker has a comparatively weak bill that struggles against hard wood, tying this European species closely to old, softer-timbered deciduous forest. Read the guide →
Amphibians NE Midwife Toad Alytidae A midwife toad is a small European frog whose male wraps the strings of eggs around his own hind legs and carries them for weeks, wetting them at ponds until they are ready to hatch. Read the guide →
Birds VU Military Macaw Ara militaris The military macaw wears a mostly green body reminiscent of an old-fashioned military uniform, and unlike most lowland macaws it favours foothill forest at higher elevation. Read the guide →
Reptiles LC Milk Snake Lampropeltis triangulum The milk snake is a harmless kingsnake whose red, black and yellow bands mimic the venomous coral snake. Its name comes from a false old belief that it milked cows. Read the guide →
Fish LC Milkfish Chanos chanos The milkfish is the sole living species in its entire family, a silvery, ancient-lineage fish farmed across Southeast Asia for centuries and celebrated in the Philippines as a national culinary icon. Read the guide →
Invertebrates LC Milkweed Bug Oncopeltus fasciatus The milkweed bug advertises its toxicity in bold orange and black, feeding almost entirely on milkweed seeds and storing the plant's defensive toxins without any apparent ill effect. Read the guide →
Invertebrates NE Millipede Diplopoda A millipede is a slow, rounded, many-legged animal with two pairs of legs on most body segments, feeding on dead leaves and defending itself with toxic or foul chemicals rather than a bite. Read the guide →
Reptiles LC Mimic Glass Lizard Ophisaurus mimicus The mimic glass lizard closely resembles its more common slender glass lizard relative, a similarity close enough that the species went undescribed for years. Read the guide →
Invertebrates DD Mimic Octopus Thaumoctopus mimicus The mimic octopus can flatten, twist, and color itself into convincing impressions of a lionfish, a sea snake, or a flatfish, switching disguises within seconds depending on which predator is nearby. Read the guide →
Amphibians LC Mimic Poison Frog Ranitomeya imitator The mimic poison frog copies the colours of three more-toxic dart frogs in different Peruvian valleys, the first amphibian proven to be a mimic. It is also one of very few frogs that mates for life. Read the guide →
Birds LC Minivet Pericrocotus spp. The minivet moves through forest canopy in small, colourful flocks, males often flame-red or orange against duller females, a pattern of sexual dimorphism that makes flock composition easy to read. Read the guide →
Amphibians LC Mink Frog Lithobates septentrionalis The mink frog is a small green frog of cold northern lakes that smells of rotten onions or mink when handled, and whose call sounds like a stick tapped fast against a hollow log. Read the guide →
Mammals LC Minke Whale Balaenoptera acutorostrata The minke whale is the smallest of the baleen whales regularly encountered by whale watchers, a curious, fast-swimming species distinctive for the white band crossing each of its flippers. Read the guide →
Invertebrates NE Minotaur Beetle Typhaeus typhoeus The minotaur beetle is a glossy black dung beetle whose male carries three forward-pointing horns, and whose pairs dig deep burrows on sandy heaths and stock them with dung. Read the guide →
Birds LC Mississippi Kite Ictinia mississippiensis The Mississippi kite catches large flying insects on the wing and often eats them mid-flight, a feeding style so agile that the bird rarely needs to touch down between one meal and the next. Read the guide →
Reptiles LC Mississippi Map Turtle Graptemys pseudogeographica kohnii The Mississippi map turtle carries a small crescent-shaped mark behind each eye, a feature that stands out against the fine pattern of light lines covering the rest of the shell and skin. Read the guide →
Amphibians LC Mississippi Slimy Salamander Plethodon mississippi The Mississippi slimy salamander occupies its own corner of the old slimy salamander complex, one of more than a dozen genetically distinct species that look nearly identical under the same pattern. Read the guide →
Birds LC Mockingbird Mimus A mockingbird is a grey American songbird named for its ability to copy the songs of other birds, plus frogs, car alarms, and squeaky gates, a repertoire of hundreds of phrases that grows for life. Read the guide →
Reptiles VU Mojave Fringe-Toed Lizard Uma scoparia The Mojave fringe-toed lizard has snowshoe-like fringed toes for racing across loose sand, and can dive beneath the surface to vanish from predators entirely. Read the guide →
Reptiles LC Mojave Rattlesnake Crotalus scutulatus The Mojave rattlesnake carries a rare neurotoxic venom component alongside typical tissue-destroying compounds, making some of its bites considerably more medically serious than expected. Read the guide →
Mammals NE Mole Talpidae A mole is a small, cylindrical mammal built for a life underground, with reversed spade-shaped hands, hidden eyes, and blood that stores extra oxygen for working in stale tunnel air. Read the guide →
Invertebrates LC Mole Crab Emerita spp. The mole crab buries itself backward into wet sand within seconds of each retreating wave, extending feathery antennae to filter plankton from the surf before the next wave arrives. Read the guide →
Invertebrates NE Mole Cricket Gryllotalpidae The mole cricket is a burrowing cricket with wide, mole-like digging forelegs, and the male sings from a horn-shaped tunnel that works as a loudspeaker to carry his call across a field. Read the guide →
Amphibians NE Mole Salamander Ambystomatidae A mole salamander is a stout burrowing amphibian of North America that spends most of the year underground and emerges on rainy nights to breed in temporary pools; the family includes the axolotl. Read the guide →
Reptiles LC Mole Skink Plestiodon egregius The mole skink spends much of its life underground in loose sandy soil, and juveniles carry a bright pink or reddish tail that fades as the lizard matures. Read the guide →
Mammals LC Molina's Hog-nosed Skunk Conepatus chinga Molina's hog-nosed skunk ranges across a far broader stretch of South America than its more southerly Patagonian relative, using an elongated snout to root out food from the soil. Read the guide →
Fish LC Molly Poecilia A molly is a hardy livebearing fish of coastal fresh and brackish water from the southern US to South America, and one species, the Amazon molly, is an all-female fish that clones itself. Read the guide →
Birds VU Moluccan Cockatoo Cacatua moluccensis The moluccan cockatoo raises a spectacular salmon-pink crest when excited or alarmed, one of the largest and most striking white cockatoo species, restricted to a single group of Indonesian islands. Read the guide →
Invertebrates VU Monarch Butterfly Danaus plexippus The monarch butterfly makes a 4,000 km migration that takes several generations, guided by a sun compass. Learn how milkweed makes it toxic and why monarch numbers have crashed. Read the guide →
Mammals LC Mongolian Gerbil Meriones unguiculatus The Mongolian gerbil is the common pet gerbil, a social burrower of Mongolia's dry steppe that drums its hind feet on the ground to warn its family of danger. Read the guide →
Mammals LC Mongoose Herpestidae A mongoose is a small, agile African and Asian carnivore famous for killing venomous snakes, relying mainly on speed and partial venom resistance, and the meerkat is one of about 34 species. Read the guide →
Mammals CR Mongoose Lemur Eulemur mongoz The mongoose lemur is one of the few lemur species found outside Madagascar, with a small introduced population on the Comoro Islands, and shows unusually flexible activity patterns. Read the guide →
Mammals LC Monito del Monte Dromiciops gliroides The monito del monte is a living fossil marsupial, the sole surviving member of an ancient lineage more closely related to Australian marsupials than to any other mammal in South America. Read the guide →
Reptiles NE Monitor Lizard Varanidae A monitor lizard is a big, active predator with a forked tongue, bird-like lungs, and rare stamina for a reptile; the group includes the Komodo dragon, the largest lizard alive. Read the guide →
Birds LC Monk Parakeet Myiopsitta monachus The monk parakeet is the only parrot species that builds a stick nest rather than nesting in a tree cavity, sometimes constructing structures large enough to house dozens of pairs. Read the guide →
Mammals NE Monkey Simiiformes (excluding apes) A monkey is any of about 260 primate species, split into the flat-nosed New World monkeys of the Americas, some with a gripping tail, and the narrow-nosed Old World monkeys of Africa and Asia. Read the guide →
Reptiles NE Monkey-tailed Skink Corucia zebrata The monkey-tailed skink of the Solomon Islands is the largest skink in the world, a tree-dwelling herbivore with a grasping tail that gives birth to one enormous baby and lives in a family group. Read the guide →
Fish LC Monkfish Lophius The monkfish is a bottom-dwelling ambush predator so famously unattractive that it is usually sold with only its tail meat visible, prized for a firm, sweet texture often compared to lobster. Read the guide →
Reptiles LC Monocled Cobra Naja kaouthia The monocled cobra is a brown-to-olive cobra of South and Southeast Asia, marked by a single ring on the back of its hood, that lives in wetlands and paddies and whose bite can destroy tissue. Read the guide →
Reptiles LC Montpellier Snake Malpolon monspessulanus The Montpellier snake is one of Europe's largest snakes, a fast, rear-fanged olive-brown hunter of dry Mediterranean scrub with fierce-looking brow ridges, whose venom is mild to people. Read the guide →
Invertebrates NE Moon Jellyfish Aurelia aurita The moon jellyfish is the pale, four-ringed jelly seen drifting in harbours and aquarium tanks worldwide. Its sting is too weak to feel through most skin, and it has no brain at all. Read the guide →
Invertebrates LC Moon Snail Neverita A moon snail drills a nearly perfect round hole through another mollusk's shell using an acid-coated tongue, leaving behind one of the ocean's most recognisable calling cards. Read the guide →
Fish LC Mooneye Hiodon tergisus The mooneye carries unusually large, reflective eyes suited to feeding in low light, a silvery North American fish belonging to one of the continent's few surviving primitive freshwater fish families. Read the guide →
Fish NE Moonlight Gourami Trichopodus microlepis The moonlight gourami carries a pale, silvery-green body with a faint glowing quality, making it one of the more subtly elegant gouramis kept in home aquariums. Read the guide →
Amphibians LC Moor Frog Rana arvalis The moor frog is an ordinary brown frog most of the year, but for a few days during the spring breeding frenzy the males turn a vivid sky blue. The colour fades within a week. Read the guide →
Reptiles LC Moorish Gecko Tarentola mauritanica The Moorish gecko is the stout, bumpy-skinned gecko on Mediterranean walls, clinging to sheer stone and glass on toe pads gripped by microscopic hairs, and active by day as well as night. Read the guide →
Fish LC Moorish Idol Zanclus cornutus The Moorish idol is a disc-shaped reef fish banded in white, black, and yellow, with a long trailing dorsal streamer. Its diet of sponges makes it one of the hardest fish to keep in an aquarium. Read the guide →
Mammals LC Moose Alces alces The moose is the largest deer on Earth, tall enough to wade chest-deep and dive for water plants. Learn about its two-metre antlers and why warming winters are killing it with ticks. Read the guide →
Fish LC Moray Eel Muraenidae A moray eel is a reef-dwelling predator with a second set of jaws hidden in its throat that shoots forward to grab and drag prey down, a mechanism found in almost no other fish. Read the guide →
Reptiles LC Morelet's Crocodile Crocodylus moreletii Morelet's crocodile is a medium-sized freshwater crocodile of Mexico, Belize, and Guatemala that recovered after heavy hunting for its skin and is now classed as Least Concern. Read the guide →
Invertebrates LC Mormon Cricket Anabrus simplex The Mormon cricket is not a cricket but a big flightless katydid of the American West that forms marching bands of millions, driven forward by the cannibals behind them. Read the guide →
Invertebrates NE Mosquito Anopheles gambiae The mosquito kills more people than any other animal on Earth, spreading malaria, dengue, and other diseases to hundreds of millions a year. Only the females bite, for the protein to make eggs. Read the guide →
Fish LC Mosquitofish Gambusia A mosquitofish is a small, hardy North American livebearer released worldwide to eat mosquito larvae, which then became one of the most damaging invasive fish, called the plague minnow in Australia. Read the guide →
Amphibians LC Mossy Frog Theloderma corticale A mossy frog is a Vietnamese stream frog whose green, black, and rust-brown skin makes it look just like a clump of moss on a wet rock, and when frightened it rolls into a ball and plays dead. Read the guide →
Reptiles LC Mossy Leaf-tailed Gecko Uroplatus sikorae The mossy leaf-tailed gecko mimics lichen-covered bark so precisely that its mottled green-brown skin can make it nearly invisible on the exact tree it is resting on. Read the guide →
Invertebrates NE Moth Lepidoptera A moth is a scaled-winged insect of the order Lepidoptera, which outnumbers butterflies about nine to one, and many adults never feed at all, living only long enough to mate and lay eggs. Read the guide →
Birds LC Motmot Momotidae A motmot is a brilliantly coloured tropical bird best known for a long tail ending in two bare, racket-shaped tips that it grooms into shape itself and swings side to side like a pendulum. Read the guide →
Birds LC Mottled Owl Ciccaba virgata The mottled owl blends almost perfectly into tree bark with its camouflaged brown plumage, one of the most widespread forest owls across the Neotropics. Read the guide →
Birds NT Mottled Petrel Pterodroma inexpectata The mottled petrel breeds only on a small number of New Zealand subantarctic islands, then migrates across the entire Pacific Ocean to spend the non-breeding season in the North Pacific. Read the guide →
Fish LC Mottled Sculpin Cottus bairdii The mottled sculpin has no swim bladder at all, so it simply sinks and stays pinned to the streambed, camouflaged so effectively it can vanish in plain sight. Read the guide →
Amphibians LC Mount Lyell Salamander Hydromantes platycephalus The Mount Lyell salamander survives at higher elevation than almost any other North American amphibian, sheltering among granite boulders in the Sierra Nevada mountains. Read the guide →
Mammals LC Mountain Beaver Aplodontia rufa Despite its name, the mountain beaver is not related to true beavers at all, and is considered one of the most primitive living rodents still found today. Read the guide →
Birds LC Mountain Bluebird Sialia currucoides The mountain bluebird is a paler sky-blue relative of the eastern and western bluebirds, hovering over open high country to spot insects rather than sallying from a fixed perch. Read the guide →
Birds LC Mountain Caracara Phalcoboenus megalopterus The mountain caracara patrols high Andean grassland on foot as often as in flight, hunting small prey and scavenging carrion at altitudes most birds avoid. Read the guide →
Birds LC Mountain Chickadee Poecile gambeli The mountain chickadee caches large numbers of food items each autumn across steep, high-elevation forest, relying on a spatial memory sharp enough to relocate many of them through a long winter. Read the guide →
Amphibians CR Mountain Chicken Frog Leptodactylus fallax The mountain chicken is one of the world's largest frogs, a Caribbean giant once eaten as a national dish. Hunting, a volcano, and disease have cut it to a few hundred, almost all on one island. Read the guide →
Amphibians LC Mountain Chorus Frog Pseudacris brachyphona The mountain chorus frog calls from shallow temporary pools tucked into Appalachian hillsides, a small, well-camouflaged frog whose scattered populations have already contracted in parts of its range. Read the guide →
Mammals EN Mountain Gazelle Gazella gazella The mountain gazelle has lost an estimated four-fifths of its population in recent decades, a rocky-hillside specialist of the Middle East now classified as Endangered. Read the guide →
Mammals LC Mountain Goat Oreamnos americanus The mountain goat navigates near-vertical cliffs most other large mammals could never attempt, using hooves with a soft, grippy centre to balance on ledges barely wider than its own feet. Read the guide →
Mammals EN Mountain Nyala Tragelaphus buxtoni The mountain nyala survives only in a small pocket of Ethiopian highland forest, a spiral-horned antelope found nowhere else on Earth and now classified as Endangered. Read the guide →
Mammals CR Mountain Pygmy Possum Burramys parvus The mountain pygmy possum is the only Australian marsupial that hibernates, a mouse-sized alpine animal known from fossils before a living one was found, now endangered as its moth food fails. Read the guide →
Birds LC Mountain Quail Oreortyx pictus The mountain quail is the largest quail species native to North America, and rather than flying south for winter it walks downhill on foot, covering entire mountain slopes step by step. Read the guide →
Fish LC Mountain Redbelly Dace Chrosomus oreas A breeding male mountain redbelly dace turns a brilliant crimson along its belly and cheeks, one of the most vivid seasonal colour transformations of any small fish in Appalachian streams. Read the guide →
Mammals EN Mountain Reedbuck Redunca fulvorufula The mountain reedbuck trades the reedbeds of its lowland relative for rocky hillsides and mountain grassland, a small grey antelope now classified as Endangered after sharp recent declines. Read the guide →
Mammals EN Mountain Tapir Tapirus pinchaque The mountain tapir is the smallest and woolliest tapir, an Endangered browser of the high Andes that lives in cloud forest and paramo up to about 4,000 metres above sea level. Read the guide →
Mammals LC Mountain Vizcacha Lagidium viscacia The mountain vizcacha is a rabbit-like rodent of the high Andes, basking on sun-warmed rocks between short bursts of grazing on the sparse vegetation of its cold, thin-aired habitat. Read the guide →
Amphibians EN Mountain Yellow-legged Frog Rana muscosa Once the most abundant amphibian in California's high Sierra, the mountain yellow-legged frog was driven to the brink by stocked trout and a fungal disease, then partly rescued by removing the fish. Read the guide →
Mammals VU Mountain Zebra Equus zebra The mountain zebra is a Vulnerable zebra of the rocky highlands of southern Africa, with a dewlap under its chin and a grid-iron stripe pattern on its rump, and was once down to a few dozen animals. Read the guide →
Invertebrates LC Mourning Cloak Nymphalis antiopa The mourning cloak survives winter as an adult butterfly hidden beneath loose tree bark, emerging on the first warm days of late winter well before most butterflies have even left the chrysalis. Read the guide →
Birds LC Mourning Dove Zenaida macroura The mourning dove is one of the most abundant birds in North America, the source of the soft owl-like cooing heard across suburbs and farmland, and also the most hunted game bird on the continent. Read the guide →
Reptiles LC Mourning Gecko Lepidodactylus lugubris The mourning gecko is an all-female species that reproduces entirely by cloning, with no males ever documented, and it has spread across the Pacific largely by hitchhiking in cargo shipments. Read the guide →
Birds LC Mourning Sierra-finch Phrygilus fruticeti The mourning sierra-finch is marked by dark grey plumage and chestnut flanks, a distinctively patterned finch found across Andean and Patagonian scrub. Read the guide →
Birds LC Mousebird Coliidae A mousebird gets its name from scurrying and creeping through dense vegetation on short legs like a small rodent, belonging to one of the smallest, most distinctive bird orders alive. Read the guide →
Birds LC Moustached Turca Pteroptochos megapodius The moustached turca is a large, ground-dwelling bird of central Chile, more often heard calling loudly through dense scrub than actually seen. Read the guide →
Reptiles LC Mozambique Spitting Cobra Naja mossambica The Mozambique spitting cobra is a medium-sized, olive-brown cobra of southeastern Africa with pink-edged throat scales, that spits venom at the eyes and whose bite can destroy tissue. Read the guide →
Invertebrates LC Mud Dauber Sceliphron and relatives The mud dauber builds tube-shaped mud nests and stocks each cell with paralyzed spiders, including venomous ones, as living food for its larvae. Read the guide →
Amphibians LC Mud Salamander Pseudotriton montanus The mud salamander wears nearly the same reddish, spotted colouring as its more toxic relative the red salamander, borrowing a warning pattern it never earned toxicologically. Read the guide →
Reptiles LC Mud Snake Farancia abacura A mud snake is a glossy black-and-red, non-venomous water snake of the southeastern US that specialises in eating giant aquatic salamanders, and is the source of the hoop snake legend. Read the guide →
Fish LC Mud Sunfish Acantharchus pomotis The mud sunfish tolerates the acidic, tannin-stained blackwater swamps of the coastal plain, often sitting motionless on the bottom rather than swimming like most of its more active relatives. Read the guide →
Reptiles LC Mud Turtle Kinosternon A mud turtle is a small American freshwater turtle, close kin to the musk turtle, that can close its shell almost completely with a double hinge and often walks overland between drying ponds. Read the guide →
Amphibians LC Mudpuppy Necturus maculosus The mudpuppy is a large salamander that never leaves the water or loses its feathery red external gills. It stays active under ice all winter and can live 20 years or more in a single river. Read the guide →
Fish NE Mudskipper Oxudercinae The mudskipper is an amphibious goby of tropical mangrove mudflats that spends low tide out of the water, breathing through its skin, walking on its front fins, and digging a burrow in the mud. Read the guide →
Reptiles VU Mugger Crocodile Crocodylus palustris The mugger is a broad-snouted South Asian crocodile of marshes and village reservoirs, a burrow-digging predator up to about 4 metres that has recovered in India after decades of hide hunting. Read the guide →
Mammals LC Mule Deer Odocoileus hemionus The mule deer bounces across rugged terrain using a stiff-legged gait called stotting, launching all four feet off the ground at once, an escape style suited to steep, broken country over open plains. Read the guide →
Reptiles LC Mulga Snake Pseudechis australis The mulga snake, or king brown, is a large, heavy-bodied Australian snake of arid country that delivers large amounts of venom, eats other snakes, and lays eggs rather than bearing live young. Read the guide →
Fish LC Mullet Mugilidae A mullet is a schooling coastal fish that grazes algae and organic mud off the bottom with a muscular gizzard-like stomach, and it is famous for leaping clear of the water for no fully agreed reason. Read the guide →
Fish LC Mummichog Fundulus heteroclitus The mummichog tolerates swings in salinity, temperature, and oxygen that would kill most fish outright, and its genetic hardiness has made it one of the most studied fish in laboratory research. Read the guide →
Mammals LC Muntjac Muntiacus reevesi The muntjac fights with a pair of small, visible tusks rather than relying only on antlers, a tiny, primitive deer nicknamed the barking deer for its dog-like alarm call. Read the guide →
Invertebrates LC Murex Snail Muricidae The murex snail's mucus gland once supplied Tyrian purple, a dye so labour-intensive to extract from thousands of snails that the colour became a symbol of royalty across the ancient Mediterranean. Read the guide →
Mammals CR Muriqui Brachyteles The muriqui is the largest primate in the Americas, known for an unusually peaceful, egalitarian social life with remarkably little aggression between group members. Read the guide →
Invertebrates NE Mushroom Coral Fungiidae The mushroom coral lives as a single large, free-moving polyp rather than a fixed colony, capable of flipping itself upright again if overturned by waves or a careless diver's fin. Read the guide →
Reptiles LC Musk Turtle Sternotherus A musk turtle is a small North American freshwater turtle that walks the bottom rather than swimming, releases a foul musk when handled, and will readily bite to defend itself. Read the guide →
Fish LC Muskellunge Esox masquinongy The muskellunge is the largest member of the pike family and the top predator of the North American lakes it lives in, an ambush hunter so hard to catch that anglers call it the fish of 10,000 casts. Read the guide →
Mammals LC Muskox Ovibos moschatus The muskox survives the Arctic winter under the warmest natural fibre known, and defends its calves by forming a horn-outward circle — a tactic that worked on wolves but not on rifles. Read the guide →
Mammals LC Muskrat Ondatra zibethicus The muskrat builds dome-shaped lodges out of cattails and mud rising straight out of the marsh, engineering wetland habitat that dozens of other species end up relying on as well. Read the guide →
Mammals LC Musky Rat-Kangaroo Hypsiprymnodon moschatus The musky rat-kangaroo is the smallest and most primitive living kangaroo relative, the only one active by day and the only one that bounds on all fours rather than hopping. Read the guide →
Invertebrates LC Mussel Mytilidae A mussel anchors itself to a rock with tough, sticky threads strong enough to survive pounding surf, forming dense colonies that filter enormous volumes of coastal water while never moving again. Read the guide →
Reptiles LC Mussurana Clelia clelia The mussurana is a large glossy Latin American snake that hunts and eats venomous pit vipers like the fer-de-lance, shrugging off their bites. Farmers protect it for keeping the deadly ones down. Read the guide →
Birds LC Mute Swan Cygnus olor The mute swan is the classic white swan of parks and rivers — one of the heaviest flying birds and a lifelong pair-bonder, with a fierce nest defence. Where introduced it wrecks wetlands. Read the guide →
Invertebrates NE Mysid Mysida The mysid carries its developing young in a pouch beneath the body just like a marsupial, earning it the nickname opossum shrimp despite not being a true shrimp at all. Read the guide →
Invertebrates NE Mystery Snail Pomacea bridgesii The mystery snail breathes with both gills and a lung, letting it live underwater or crawl out briefly to gulp air, a large, peaceful algae-grazer popular in home aquariums. Read the guide →
Mammals LC Naked Mole-Rat Heterocephalus glaber The naked mole-rat is a hairless, nearly cold-blooded burrowing rodent that lives in ant-like colonies with a single breeding queen, feels no acid pain, resists cancer, and can live past 35. Read the guide →
Reptiles LC Namaqua Chameleon Chamaeleo namaquensis The Namaqua chameleon lives on open desert sand rather than in trees, flipping from black to pale grey within minutes to control its temperature where there is almost no shade. Read the guide →
Birds LC Nanday Parakeet Aratinga nenday The nanday parakeet shows a striking black hood against a bright green body, a noisy, social parrot now established as an introduced species far outside its native South American range. Read the guide →
Amphibians NE Narrow-mouthed Frog Microhylidae A narrow-mouthed frog belongs to the largest frog family, a group of small, often plump, tiny-mouthed ant and termite specialists that includes the smallest vertebrate known. Read the guide →
Amphibians LC Narrow-Striped Dwarf Siren Pseudobranchus striatus The narrow-striped dwarf siren is one of the smallest salamanders in North America, an eel-like amphibian with only tiny front legs that spends its entire life hidden among dense aquatic vegetation. Read the guide →
Mammals EN Narrow-striped Mongoose Mungotictis decemlineata The narrow-striped mongoose is a small Madagascar carnivore with faint dark stripes down its back, restricted to one shrinking patch of dry forest on the island's west coast. Read the guide →
Invertebrates NE Narrow-Winged Mantis Tenodera angustipennis The narrow-winged mantis is often mistaken for its larger relative the Chinese mantis, but a slimmer body and narrower wings set this introduced predator apart across eastern grasslands and fields. Read the guide →
Mammals LC Narwhal Monodon monoceros The narwhal is an Arctic whale whose male grows a spiralled tusk up to three metres long — a single tooth packed with millions of nerve endings. It dives deeper than almost any marine mammal. Read the guide →
Fish CR Nassau Grouper Epinephelus striatus The Nassau grouper once gathered by the tens of thousands to spawn at the same few Caribbean reefs each winter. Fishing those predictable aggregations collapsed the species, now Critically Endangered. Read the guide →
Mammals LC Natal Multimammate Mouse Mastomys natalensis The Natal multimammate mouse is a prolific African rodent with many pairs of nipples whose numbers can explode after rains, and it is the main natural host of Lassa virus in West Africa. Read the guide →
Mammals LC Nathusius's Pipistrelle Pipistrellus nathusii Nathusius's pipistrelle is a small European bat that makes one of the longest migrations of any bat, flying more than two thousand kilometres between northeastern and southwestern Europe. Read the guide →
Mammals LC Natterer's Bat Myotis nattereri Natterer's bat is a pale-bellied European woodland bat with a fringe of stiff hairs along its tail membrane that gleans spiders and flies from leaves and walls. Read the guide →
Amphibians LC Natterjack Toad Epidalea calamita The natterjack toad runs instead of hopping and has the loudest call of any amphibian in Europe, heard two kilometres off. It breeds in shallow pools, racing to transform before they dry out. Read the guide →
Invertebrates NE Nautilus Nautilidae A nautilus is a deep-reef cephalopod that has kept its coiled external shell for 500 million years, adjusting gas in the sealed chambers behind it to hover almost weightless. Read the guide →
Fish LC Needlefish Tylosurus crocodilus The needlefish is a long, silver, surface fish with a beak full of fine teeth. Startled at night, it leaps from the water at speed like a thrown javelin, and it has impaled and even killed people. Read the guide →
Fish LC Neon Goby Elacatinus oceanops The neon goby runs a tiny cleaning station on the reef, picking parasites off much larger fish that line up and wait patiently for their turn to be serviced. Read the guide →
Fish LC Neon Tetra Paracheirodon innesi A neon tetra is an Amazon blackwater fish, one of the most popular aquarium fish, whose electric-blue stripe is structural colour it can switch off at night, and it needs a school to feel secure. Read the guide →
Mammals NT Neotropical Otter Lontra longicaudis The neotropical otter has the broadest range of any otter species in the Americas, found from tropical Mexican rivers all the way south into the cooler waters of northern Patagonia. Read the guide →
Invertebrates NE Net-casting Spider Deinopidae The net-casting spider hangs head-down holding a stretchy web between its front legs, then throws it over passing prey like a cast net. Two of its eyes are huge, for night vision said to beat a cat's. Read the guide →
Invertebrates LC Net-Winged Beetle Lycidae The net-winged beetle produces bitter, distasteful chemicals so effective that numerous harmless insects have evolved to copy its bold warning coloration for protection they never actually earned. Read the guide →
Amphibians VU Neuse River Waterdog Necturus lewisi The Neuse River waterdog is found only within two river systems in North Carolina, remaining fully aquatic and gilled for its entire life while population numbers continue a long, slow decline. Read the guide →
Birds LC New Caledonian Crow Corvus moneduloides The New Caledonian crow makes and carries hooked twig tools and barbed tools cut from leaf edges, uses one tool to reach another, and passes improved tool designs down through generations. Read the guide →
Reptiles LC New Guinea Crocodile Crocodylus novaeguineae The New Guinea crocodile is a dark, medium-sized freshwater crocodile of the swamps, rivers, and lakes of New Guinea, and the close relative of the rare Philippine crocodile. Read the guide →
Amphibians LC New Jersey Chorus Frog Pseudacris kalmi The New Jersey chorus frog was only recognised as its own species after study split it from the upland and southern chorus frogs, occupying a narrow strip of coastal plain habitat between them. Read the guide →
Amphibians LC New Mexico Spadefoot Spea multiplicata The New Mexico spadefoot spends most of the year buried underground, emerging explosively after monsoon rains, its tadpoles developing faster than almost any amphibian to beat a drying pool. Read the guide →
Reptiles LC New Mexico Whiptail Aspidoscelis neomexicana The New Mexico whiptail is an entirely female species that reproduces by parthenogenesis, laying fertile eggs without a male, a trait that made it the official state reptile of New Mexico. Read the guide →
Mammals LC New Zealand Fur Seal Arctocephalus forsteri The New Zealand fur seal can dive deeper and longer than most other fur seals, descending several hundred metres for squid, a species that has expanded significantly since recovering from hunting. Read the guide →
Invertebrates NE New Zealand Glowworm Arachnocampa luminosa The New Zealand glowworm is the larva of a fungus gnat that lights up cave roofs with a blue-green glow, then catches midges on dangling lines of sticky silk beads, like a bioluminescent spider. Read the guide →
Mammals EN New Zealand Sea Lion Phocarctos hookeri The New Zealand sea lion is one of the rarest sea lion species on Earth, breeding mainly on the remote Auckland and Campbell Islands and venturing unusually far inland into forest. Read the guide →
Birds VU New Zealand Storm-petrel Fregetta maoriana The New Zealand storm-petrel was believed extinct for over a century until a small population was rediscovered at sea in 2003, one of the most remarkable seabird rediscoveries of modern times. Read the guide →
Amphibians NE Newt Pleurodelinae A newt is a small salamander that returns to water each spring to breed, where the male grows a crest and courts by fanning pheromones with his tail; the young spend a land phase called an eft. Read the guide →
Reptiles LC Night Lizard Xantusiidae A night lizard is a small, secretive reptile that gives birth to live young, can live for decades, and spends nearly its entire life hidden under a single rock or log rather than moving around. Read the guide →
Reptiles LC Night Snake Hypsiglena spp. The night snake has vertical, cat-like pupils unlike most colubrids, a small, mildly venomous rear-fanged hunter that stays hidden through the desert day and only comes out once the heat fades. Read the guide →
Birds LC Nightingale Luscinia megarhynchos A nightingale is a plain brown bird of dense thickets, famous far beyond its looks for a loud, rich, varied song that the male delivers through the night as well as the day to win a passing mate. Read the guide →
Birds LC Nightjar Caprimulgidae A nightjar is a camouflaged nocturnal bird with a huge gaping mouth that scoops up moths in flight, lays its eggs on bare ground, and was once wrongly believed to suckle milk from goats. Read the guide →
Reptiles LC Nile Crocodile Crocodylus niloticus The Nile crocodile is Africa's largest predator and, by number of human deaths, one of the most dangerous animals on the continent — and yet an unusually attentive reptile parent. Read the guide →
Reptiles LC Nile Monitor Varanus niloticus The Nile monitor is one of Africa's largest lizards, a powerful swimmer known to raid crocodile nests for eggs, and it has established a damaging invasive population in Florida. Read the guide →
Fish LC Nile Perch Lates niloticus The Nile perch is a two-metre African predator. Stocked into Lake Victoria last century, it helped drive hundreds of the lake's unique cichlids to extinction and built a huge export fishery. Read the guide →
Fish LC Nile Tilapia Oreochromis niloticus The Nile tilapia is farmed in more countries than almost any other freshwater fish, a mouth-brooding species whose females carry fertilized eggs and newly hatched young safely inside their own mouths. Read the guide →
Mammals LC Nilgai Boselaphus tragocamelus The nilgai is the largest antelope in Asia, its name meaning blue cow in reference to the blue-grey colouring of mature males, a species widely protected in India for its resemblance to cattle. Read the guide →
Mammals LC Nine-banded Armadillo Dasypus novemcinctus The nine-banded armadillo always has identical quadruplets, can hold its breath to walk across river bottoms, jumps straight up when startled, and is one of the few animals that carries leprosy. Read the guide →
Fish LC Ninespine Stickleback Pungitius pungitius The ninespine stickleback rarely has exactly nine spines despite its name, and males build and guard a nest the way few fish parents ever do. Read the guide →
Invertebrates NT Noble Chafer Gnorimus nobilis The noble chafer is a shiny green scarab beetle whose larvae live in the rotting heartwood of old fruit trees, and which has become rare across Europe as old orchards have vanished. Read the guide →
Invertebrates NE Noble False Widow Steatoda nobilis The noble false widow is a glossy brown spider with a pale skull-like mark that has spread from Madeira across Europe, building tangled webs in sheds and walls and rarely biting people. Read the guide →
Invertebrates CR Noble Pen Shell Pinna nobilis The noble pen shell is the largest bivalve of the Mediterranean, a fan-shaped giant that stands upright in seagrass, once spun sea silk, and has been devastated by a recent mass-mortality epidemic. Read the guide →
Mammals LC Noctule Nyctalus noctula The noctule is a large, golden-brown European bat that flies high and fast, often emerging before sunset, and roosts mainly in tree holes. Read the guide →
Mammals LC North African Elephant Shrew Elephantulus rozeti The North African elephant shrew is the only member of its entire order found outside sub-Saharan Africa, holding on in the rocky, arid terrain of the Atlas Mountains and surrounding desert. Read the guide →
Mammals LC North American Beaver Castor canadensis The North American beaver is the continent's largest rodent and its most powerful ecosystem engineer, felling trees and damming streams to build the ponds it lives in. Learn how it works. Read the guide →
Mammals LC North American Porcupine Erethizon dorsatum The North American porcupine is a large, slow, tree-climbing rodent armed with 30,000 barbed quills that work deeper once they strike, and it will gnaw a canoe paddle to pieces for the salt. Read the guide →
Mammals LC North American River Otter Lontra canadensis The North American river otter turns snow-covered riverbanks into a playground, tobogganing on its belly down slick slopes purely, it seems, for the fun of it, between serious bouts of fishing. Read the guide →
Mammals CR North Atlantic Right Whale Eubalaena glacialis The North Atlantic right whale has declined to only a few hundred individuals, one of the most endangered large whales, its slow, coastal habits making it especially vulnerable to ships and nets. Read the guide →
Birds VU North Island Brown Kiwi Apteryx mantelli The kiwi is a chicken-sized flightless New Zealand bird that behaves like a mammal — it forages by smell at night, has whiskers and heavy bones, and lays a huge egg for its size. Read the guide →
Reptiles LC Northern Alligator Lizard Elgaria coerulea The northern alligator lizard tolerates cooler temperatures than most lizards, remaining active at elevations and latitudes that would leave many other reptiles too cold to move. Read the guide →
Mammals LC Northern Bat Eptesicus nilssonii The northern bat is one of the most cold-tolerant bats in the world, ranging north of the Arctic Circle in Scandinavia and sometimes hunting in the continuous daylight of the northern summer. Read the guide →
Birds NT Northern Bobwhite Colinus virginianus The northern bobwhite calls its own name across open farmland, a clear whistled "bob-WHITE" that has made it one of the most recognisable game bird sounds in North America. Read the guide →
Mammals LC Northern Brown Bandicoot Isoodon macrourus The northern brown bandicoot digs small conical pits across lawns and gardens each night while foraging, a common sight across much of coastal northern and eastern Australia. Read the guide →
Birds LC Northern Cardinal Cardinalis cardinalis The northern cardinal is the brilliant red songbird of eastern US gardens — one of the few female songbirds that sings, a fierce window-attacker in spring, and the state bird of seven states. Read the guide →
Amphibians CR Northern Corroboree Frog Pseudophryne pengilleyi The northern corroboree frog is a tiny yellow-and-black striped frog of Australian mountain bogs, one of the few animals that makes its own poison and one of the most endangered amphibians alive. Read the guide →
Amphibians LC Northern Cricket Frog Acris crepitans The northern cricket frog is a thumbnail-sized frog whose call sounds like two pebbles clicked together, faster and faster. It is one of the best jumpers of any vertebrate for its size. Read the guide →
Amphibians LC Northern Dusky Salamander Desmognathus fuscus The northern dusky salamander holds its tail in a distinctive knife-edged, flattened profile, a subtle build that helps identify it among a large group of closely related stream-dwelling salamanders. Read the guide →
Mammals LC Northern Elephant Seal Mirounga angustirostris The northern elephant seal can dive deeper than 1,500 metres and hold its breath nearly two hours, a massive seal that rebounded from under a hundred survivors in the 1800s to hundreds of thousands. Read the guide →
Birds LC Northern Flicker Colaptes auratus The northern flicker is one of the few North American woodpeckers that regularly feeds on the ground, hopping across lawns and open fields to dig ants directly out of their underground nests. Read the guide →
Mammals LC Northern Flying Squirrel Glaucomys sabrinus The northern flying squirrel cannot actually fly, but a furred membrane between its limbs lets it glide silently between trees, an entirely nocturnal life spent almost never touching the ground. Read the guide →
Mammals VU Northern Fur Seal Callorhinus ursinus The northern fur seal has the densest fur of any mammal, packing hundreds of thousands of hairs into a square inch, a density that made it a target for the fur trade before international protection. Read the guide →
Birds LC Northern Gannet Morus bassanus The northern gannet dives into the sea from 45 metres, folding into an arrow that hits the water at 100 km/h. Air sacs under its skin cushion the blow and its nostrils open inside the bill. Read the guide →
Birds LC Northern Giant Petrel Macronectes halli The northern giant petrel scavenges carcasses of seals and penguins with a massive, hooked bill capable of tearing through tough hide, often thrusting its entire head inside a carcass to feed. Read the guide →
Mammals LC Northern Grasshopper Mouse Onychomys leucogaster The northern grasshopper mouse is a carnivorous desert mouse that howls like a tiny wolf, hunts other mice, and eats bark scorpions whose venom it has turned into a painkiller. Read the guide →
Mammals CR Northern Hairy-Nosed Wombat Lasiorhinus krefftii The northern hairy-nosed wombat is one of the rarest mammals on Earth, its entire wild population once reduced to roughly 35 animals in a single Queensland park. Read the guide →
Birds LC Northern Harrier Circus hudsonius The northern harrier hunts by sound almost as much as sight, using an owl-like facial disc to funnel the rustle of hidden prey toward its ears while gliding low and slow over open grassland and marsh. Read the guide →
Fish LC Northern Hogsucker Hypentelium nigricans The northern hogsucker roots along stream bottoms with a hog-like snout, flipping rocks for insect larvae, a style so effective other fish trail behind to catch what it stirs loose. Read the guide →
Birds LC Northern Jacana Jacana spinosa The northern jacana walks on floating lily pads with enormous long toes. Females are larger, hold territories of several males, and leave each male to build the nest and raise the chicks alone. Read the guide →
Amphibians LC Northern Leopard Frog Lithobates pipiens The northern leopard frog was once the most common frog across much of North America and the standard classroom dissection specimen, but it has vanished from large parts of its western range. Read the guide →
Fish LC Northern Madtom Noturus stigmosus The northern madtom hides beneath flat rocks and debris by day, emerging at night to hunt, using venomous spines as its main defence against predators that might otherwise make an easy meal of it. Read the guide →
Birds LC Northern Mockingbird Mimus polyglottos The northern mockingbird is a plain grey songbird with an extraordinary voice, learning 50 to 200 songs copied from other birds and from machines, and it dive-bombs any cat or person near its nest. Read the guide →
Reptiles LC Northern Pacific Rattlesnake Crotalus oreganus oreganus The northern Pacific rattlesnake ranges farther north and higher than almost any other rattlesnake in North America, staying active in cooler conditions that keep most other rattlesnakes underground. Read the guide →
Birds LC Northern Parula Setophaga americana The northern parula builds its nest almost exclusively inside hanging clumps of Spanish moss or beard lichen, tucking the whole structure into a natural curtain most predators never think to search. Read the guide →
Fish LC Northern Pike Esox lucius The northern pike is the ambush predator of cool fresh water across the northern hemisphere, a long green fish with a duck-bill snout, hundreds of teeth, and a lunge like a released spring. Read the guide →
Fish LC Northern Pikeminnow Ptychocheilus oregonensis The northern pikeminnow is the largest minnow native to North America, a predator significant enough that fisheries agencies pay anglers a bounty for every one caught to protect young salmon. Read the guide →
Birds LC Northern Pygmy-Owl Glaucidium californicum The northern pygmy-owl carries dark false eye markings on the back of its head, a decoy pattern that can make an approaching predator think the tiny owl is watching even while its real eyes face away. Read the guide →
Mammals EN Northern Quoll Dasyurus hallucatus The northern quoll has been devastated by invasive cane toads, dying after eating the toxic amphibians, and most males die en masse after a single frantic breeding season. Read the guide →
Amphibians LC Northern Red-Legged Frog Rana aurora The northern red-legged frog was once considered the same species as the California red-legged frog, until researchers split them apart based on genetic and physical differences. Read the guide →
Mammals LC Northern Right Whale Dolphin Lissodelphis borealis The northern right whale dolphin is the only North Pacific dolphin with no dorsal fin, a sleek, slender swimmer that skims low across the water rather than making the higher jumps of most dolphins. Read the guide →
Reptiles CR Northern River Terrapin Batagur baska The northern river terrapin is one of Asia's largest freshwater turtles, a plant-eating giant of estuaries and tidal rivers that nests on sandbanks and is Critically Endangered. Read the guide →
Birds EN Northern Rockhopper Penguin Eudyptes moseleyi The northern rockhopper penguin was split from its southern relative as a distinct species in 2006, and has since suffered one of the steepest population declines of any penguin. Read the guide →
Birds EN Northern Royal Albatross Diomedea sanfordi The northern royal albatross breeds at one of the only mainland albatross colonies in the world, a headland near a New Zealand city where visitors can watch the birds nest close by. Read the guide →
Birds LC Northern Saw-Whet Owl Aegolius acadicus The northern saw-whet owl is one of the smallest owls in North America, small enough to fit in a human hand, yet it migrates hundreds of kilometres each year almost entirely unnoticed. Read the guide →
Fish LC Northern Sea Robin Prionotus carolinus The northern sea robin walks along the sea floor on six finger-like legs that break away from its fins and can taste the sand, and it grunts and growls loudly with a drumming muscle. Read the guide →
Mammals LC Northern Short-Tailed Shrew Blarina brevicauda The northern short-tailed shrew is one of North America's few venomous mammals, using a paralysing bite to immobilise prey and store it alive for later, like a living pantry. Read the guide →
Fish LC Northern Snakehead Channa argus The northern snakehead breathes air, wriggles overland between ponds, and guards its young. Introduced to the US, it is a headline invasive fish officials ask anglers to kill on sight. Read the guide →
Invertebrates LC Northern Walkingstick Diapheromera femorata The northern walkingstick simply drops its eggs at random from the treetops onto the forest floor, each one disguised well enough to pass for an ordinary seed. Read the guide →
Reptiles LC Northern Water Snake Nerodia sipedon The northern water snake is a harmless fish-eating snake of North American ponds and rivers that is killed on sight across its range because it is mistaken for a venomous cottonmouth. Read the guide →
Reptiles LC Northwestern Garter Snake Thamnophis ordinoides The northwestern garter snake shows more colour variation than almost any other North American snake, with individuals from the same population ranging from solid black to bright orange-striped. Read the guide →
Amphibians LC Northwestern Salamander Ambystoma gracile The northwestern salamander produces a mild skin toxin as defense, and some populations never leave the water at all, remaining gilled and aquatic for their entire adult lives. Read the guide →
Mammals LC Norway Lemming Lemmus lemmus The Norway lemming is a bold black-and-tawny tundra rodent whose populations boom and crash in cycles, and whose famous mass suicide is a myth. Read the guide →
Invertebrates LC Norway Lobster Nephrops norvegicus The Norway lobster, or langoustine, is a slim-clawed, orange-pink burrower of muddy north-eastern Atlantic seabeds that feeds at dusk and is the source of scampi. Read the guide →
Reptiles LC Nose-horned Viper Vipera ammodytes The nose-horned viper is a zigzag-backed European viper with a soft horn on its snout, widely regarded as the most dangerous snake in Europe, found on rocky slopes across the Balkans. Read the guide →
Invertebrates NE Notch-horned Cleg Haematopota pluvialis The notch-horned cleg is a grey-brown, mottled-winged horsefly with iridescent patterned eyes whose females bite silently in damp, humid weather, drawing blood from livestock, walkers, and horses. Read the guide →
Birds LC Nubian Woodpecker Campethera nubica The Nubian woodpecker wears a golden-olive body dotted with fine spots, a common but easily overlooked hunter of ants and termites across the savanna and woodland of East Africa. Read the guide →
Invertebrates NE Nudibranch Nudibranchia A nudibranch is a shell-less sea snail, often vividly coloured, that gets its defences second-hand, stealing the stinging cells of jellyfish and the toxins of sponges and reusing them in its skin. Read the guide →
Mammals EN Numbat Myrmecobius fasciatus The numbat is a striped, squirrel-tailed marsupial that eats only termites — up to 20,000 a day, licked up with a tongue half its body length — and one of the few marsupials active only by day. Read the guide →
Fish VU Nurse Shark Ginglymostoma cirratum The nurse shark spends most of the day lying motionless on the seafloor, a docile bottom-dweller that uses powerful suction to vacuum crabs and small fish straight out of reef crevices at night. Read the guide →
Fish NT Nursehound Scyliorhinus stellaris The nursehound, or bull huss, is a stout, large-spotted catshark of rocky European seabeds that rests in caves by day, hunts at night, and lays big egg cases that wash up as mermaid's purses. Read the guide →
Birds LC Nuthatch Sitta A nuthatch is a small, stout tree bird, the only kind that habitually climbs head-first down trunks, and it wedges nuts into bark and hammers them open, which is how it got its name. Read the guide →
Birds LC Nuttall's Woodpecker Dryobates nuttallii Nuttall's woodpecker closely resembles the desert-dwelling ladder-backed woodpecker but instead makes its home in California's oak woodland. Read the guide →
Mammals LC Nyala Tragelaphus angasii A male and female nyala look so different that they could easily be mistaken for two entirely separate species, one dark grey with spiralled horns, the other reddish-brown and completely hornless. Read the guide →
Amphibians LC Oak Toad Anaxyrus quercicus The oak toad is the smallest toad in North America, a thumbnail-sized southeastern species that is active by day, eats mostly ants, and calls with a shrill peeping whistle like a flock of baby chicks. Read the guide →
Fish LC Oarfish Regalecus glesne An oarfish is the longest bony fish alive, a silver ribbon up to 8 m long that lives in the deep open ocean, swims head-up in a vertical column, and is the likely source of many sea-serpent sightings. Read the guide →
Fish VU Ocean Sunfish Mola mola The ocean sunfish is the heaviest bony fish in the world, a flattened disc with no tail that can weigh over two tonnes, basks on its side at the surface, and lays more eggs than any other vertebrate. Read the guide →
Fish CR Oceanic Whitetip Shark Carcharhinus longimanus The oceanic whitetip shark, a bold open-ocean hunter once among the most abundant large animals on the planet, is now critically endangered after decades of being finned. Read the guide →
Birds NT Ocellated Antbird Phaenostictus mcleannani The ocellated antbird dominates every army ant swarm it joins, pushing smaller antbird species aside to claim the best feeding positions at the front. Read the guide →
Reptiles NT Ocellated Lizard Timon lepidus The ocellated lizard is the largest lizard in Europe, a heavy, big-headed reptile of dry southwestern scrub and vineyards, green with a row of bright blue eye-spots down each flank. Read the guide →
Mammals LC Ocelot Leopardus pardalis The ocelot hunts almost entirely at night across dense cover, a strikingly patterned wild cat once reduced to a tiny remnant Texas population by fur hunting, now slowly recovering under conservation. Read the guide →
Amphibians LC Ocmulgee Slimy Salamander Plethodon ocmulgee The Ocmulgee slimy salamander occupies its own narrow slice of central Georgia, one of more than a dozen genetically distinct species revealed when the old slimy salamander complex was split apart. Read the guide →
Amphibians LC Ocoee Salamander Desmognathus ocoee The Ocoee salamander is one of several closely related dusky salamander species that quietly divide the southern Appalachians, distinguished mainly by subtle range and habitat differences. Read the guide →
Invertebrates NE Octopus Octopoda An octopus is a boneless, eight-armed mollusc with three hearts, the most intelligent invertebrate, able to change colour and texture in a second and to squeeze through a coin-sized gap. Read the guide →
Invertebrates NE Oil Beetle Meloe proscarabaeus The oil beetle is a plump, flightless, blue-black beetle that oozes blistering oily fluid when threatened and whose tiny larvae hitch a ride on solitary bees to steal their food stores. Read the guide →
Birds LC Oilbird Steatornis caripensis The oilbird is the world's only nocturnal, flying, fruit-eating bird. It roosts deep in dark caves in colonies of thousands, navigating by echolocation and smell, and flies far to fruiting trees. Read the guide →
Mammals EN Okapi Okapia johnstoni The okapi is the only living relative of the giraffe — a solitary rainforest browser with a long black tongue and striped zebra-like legs. It was unknown to Western science until 1901. Read the guide →
Birds EN Okinawa Rail Hypotaenidia okinawae The Okinawa rail was unknown to science until 1981, a flightless forest bird confined to a single mountainous corner of Okinawa Island that remains under constant threat from introduced predators. Read the guide →
Birds EN Okinawa Woodpecker Dendrocopos noguchii The Okinawa woodpecker survives only within the same patch of Yanbaru forest that shelters the equally endangered Okinawa rail, confined to a single Japanese island. Read the guide →
Amphibians LC Oklahoma Salamander Eurycea tynerensis The Oklahoma salamander typically stays fully aquatic for life, keeping its feathery external gills into adulthood instead of metamorphosing onto land. Read the guide →
Invertebrates LC Old World Swallowtail Papilio machaon The Old World swallowtail is a large yellow-and-black butterfly whose green caterpillar rears a smelly orange horn when threatened, and whose British form lives only in the Norfolk Broads. Read the guide →
Invertebrates LC Oleander Hawk-moth Daphnis nerii The oleander hawk-moth's caterpillar feeds safely on the toxic oleander plant, storing the plant's poisons to deter predators while the adult migrates vast distances across continents. Read the guide →
Mammals LC Olingo Bassaricyon gabbii The olingo is so easily confused with the closely related kinkajou that scientists once relied on skull and teeth to tell them apart, a fruit-eating canopy dweller lacking its cousin's grasping tail. Read the guide →
Mammals LC Olive Baboon Papio anubis The olive baboon is the most widespread baboon species in Africa, thriving across savanna, forest edge, and semi-desert alike. Read the guide →
Reptiles LC Olive Python Liasis olivaceus The olive python is a large, glossy, olive-brown constrictor of northern Australia that shelters among rocky gorges and waterholes and hunts mammals, birds, and reptiles by ambush. Read the guide →
Reptiles VU Olive Ridley Sea Turtle Lepidochelys olivacea The olive ridley is the most abundant sea turtle and the one behind the arribada — a mass nesting in which tens or hundreds of thousands of females storm a single beach over a few nights. Read the guide →
Reptiles VU Olive Ridley Turtle Lepidochelys olivacea The olive ridley turtle nests in mass gatherings so large that tens of thousands of females can come ashore on a single beach within a few nights, one of the most numerous sea turtle species left. Read the guide →
Reptiles LC Olive Sea Snake Aipysurus laevis The olive sea snake never leaves the water in its entire life, giving birth to live young at sea and absorbing extra oxygen through its own skin during long dives. Read the guide →
Birds NT Olive-Sided Flycatcher Contopus cooperi The olive-sided flycatcher sings a whistled "quick-three-beers" from the very top of a dead snag, then flies one of the longest migrations of any North American flycatcher. Read the guide →
Amphibians VU Olm Proteus anguinus The olm is a blind, cave-dwelling European salamander with pale pink skin, external gills kept for life, and the ability to survive a decade without food. It may live past 100. Read the guide →
Amphibians NT Olympic Torrent Salamander Rhyacotriton olympicus The Olympic torrent salamander survives only in the coldest splash zones of Olympic Peninsula streams, unable to tolerate water most other amphibians would find perfectly comfortable. Read the guide →
Mammals EN Onager Equus hemionus The onager, or Asiatic wild ass, is an Endangered, fast-running wild ass of the deserts and steppes of Asia, known by names such as khulan, kulan, and khur in different regions. Read the guide →
Amphibians DD One-Toed Amphiuma Amphiuma pholeter The one-toed amphiuma is the smallest and least-seen of the three amphiuma species, spending nearly its entire life burrowed into wet organic muck. Read the guide →
Fish LC Opah Lampris guttatus The opah is a dinner-table-shaped deep-ocean fish that is fully warm-blooded — it heats its whole body, including the heart and brain, using a heat-exchanger in its gills. No other fish does this. Read the guide →
Fish VU Orange Roughy Hoplostethus atlanticus The orange roughy can live well over a century, a slow-growing deep-sea fish whose remarkable longevity was discovered only after decades of fishing had already pushed populations toward collapse. Read the guide →
Invertebrates LC Orange-tip Butterfly Anthocharis cardamines The orange-tip is a spring butterfly whose males flash bright orange wingtips while females and the mottled green undersides of both sexes blend into flowers and cow parsley. Read the guide →
Birds LC Orange-winged Amazon Amazona amazonica The orange-winged amazon is one of the most common and widely kept Amazon parrots, identified by orange and blue wing patches and bright yellow cheeks. Read the guide →
Fish LC Orangespotted Sunfish Lepomis humilis The orangespotted sunfish tolerates murky, silty prairie streams better than most of its relatives, often becoming the dominant small sunfish where turbid water pushes pickier species out. Read the guide →
Fish LC Orangethroat Darter Etheostoma spectabile The orangethroat darter's breeding males flash a vivid orange throat and blue-green banding, among the most vividly coloured of all North American stream fish. Read the guide →
Mammals CR Orangutan Pongo An orangutan is a red-haired great ape of Borneo and Sumatra, the biggest tree-living animal, solitary because its fruit is too scattered for a group, and all three species are Critically Endangered. Read the guide →
Mammals DD Orca Orcinus orca The orca is the ocean's top predator — a giant dolphin that hunts in coordinated family pods and even kills great white sharks. Learn how orca culture works and why some populations are collapsing. Read the guide →
Fish LC Orchid Dottyback Pseudochromis fridmani The orchid dottyback glows an intense magenta-violet, a small, territorial reef fish found naturally only in the northern Red Sea, where it lives in crevices and caves. Read the guide →
Invertebrates NE Orchid Mantis Hymenopus coronatus The orchid mantis is a pink-and-white rainforest predator with petal-shaped legs. It does not hide in flowers — it mimics one, and pollinating insects fly to it as if it were a bloom. Read the guide →
Mammals LC Ord's Kangaroo Rat Dipodomys ordii Ord's kangaroo rat never needs to drink water at all, extracting every drop of moisture it needs from the dry seeds that make up almost its entire diet. Read the guide →
Amphibians NT Oregon Slender Salamander Batrachoseps wrighti The Oregon slender salamander squeezes its narrow body deep into rotting logs found only in old-growth stands, a lungless amphibian restricted to one small corner of the Pacific Northwest. Read the guide →
Amphibians VU Oregon Spotted Frog Rana pretiosa An Oregon spotted frog is the most aquatic frog of the Pacific Northwest, a marsh species that has lost about 90 percent of its range and is among the most endangered amphibians in the western US. Read the guide →
Mammals LC Oribi Ourebia ourebi The oribi is a small grassland antelope with a distinctive black scent gland patch below each ear, unusual among small antelope for living in family groups rather than alone. Read the guide →
Birds LC Oriental Dwarf Kingfisher Ceyx erithacus The oriental dwarf kingfisher ranks among the smallest kingfishers in the world, a tiny burst of orange, purple, and blue that vanishes into the forest understory almost as soon as it is seen. Read the guide →
Amphibians LC Oriental Fire-bellied Toad Bombina orientalis The Oriental fire-bellied toad is a small green frog with a vivid red-and-black belly it flashes when threatened, arching into a pose called the unken reflex to advertise its toxic skin. Read the guide →
Reptiles LC Oriental Garden Lizard Calotes versicolor The oriental garden lizard, or changeable lizard, is an Asian agamid whose breeding males flush bloody red on the head and throat, a bush-climbing insect-eater common in gardens. Read the guide →
Reptiles CR Orinoco Crocodile Crocodylus intermedius The Orinoco crocodile is a large, slender-snouted crocodile of the Orinoco river basin in Colombia and Venezuela, hunted almost to extinction for its skin and now Critically Endangered. Read the guide →
Birds LC Oriole Icterus An oriole is a brilliant orange and black American songbird that weaves a hanging, sock-shaped nest, its name borrowed from an unrelated Old World bird sharing the same bold colours. Read the guide →
Amphibians LC Ornate Chorus Frog Pseudacris ornata The ornate chorus frog packs an unusually bold pattern of dark blotches and stripes onto a body barely bigger than a coin, one of the most strikingly marked of North America's small chorus frogs. Read the guide →
Birds NT Ornate Hawk-eagle Spizaetus ornatus The ornate hawk-eagle is a striking crested forest raptor of the Neotropics, identified by a rufous face and neck framing boldly banded black-and-white plumage. Read the guide →
Fish LC Oscar Fish Astronotus ocellatus An oscar is a large, interactive Amazonian cichlid kept as a pet for its dog-like personality and its habit of rearranging the tank, though it grows to 30 cm and needs a very large aquarium. Read the guide →
Birds LC Osprey Pandion haliaetus The osprey is a fish-hunting raptor on every continent but Antarctica. It dives feet-first into the water, closes a valve in its nostrils, and carries fish head-first with reversible outer toes. Read the guide →
Birds LC Ostrich Struthio camelus The ostrich is the largest and heaviest bird alive, the fastest thing on two legs, and the layer of the biggest egg of any living animal. Learn how a bird this size survives on the African plains. Read the guide →
Mammals NE Otter Lutrinae An otter is a sleek, playful member of the weasel family built for hunting in water, kept warm by dense fur rather than blubber, and the sea otter uses stone tools and holds hands while it sleeps. Read the guide →
Mammals EN Otter Civet Cynogale bennettii The otter civet has evolved webbed feet and dense, water-resistant fur strikingly similar to a true otter, despite belonging to an entirely different carnivore family. Read the guide →
Reptiles LC Ouachita Map Turtle Graptemys ouachitensis Female Ouachita map turtles grow heads and jaws so much larger than males that the two sexes eat different diets, with only females strong enough to crush hard-shelled mussels and snails. Read the guide →
Reptiles LC Oustalet's Chameleon Furcifer oustaleti Oustalet's chameleon ranks among the largest chameleon species alive, with females growing nearly as long as males despite usually being the smaller sex in most chameleons. Read the guide →
Birds LC Ovenbird Furnariidae An ovenbird, in the South American sense of the word, builds a rounded mud nest so similar in shape to an old clay baking oven that early settlers named the whole family after it. Read the guide →
Birds NE Owl Strigiformes An owl is a bird built to hunt in near-darkness, with huge fixed eyes, a head that turns most of the way round, offset ears that pinpoint sound in three dimensions, and near-silent flight. Read the guide →
Invertebrates LC Owlfly Ascalaphidae The owlfly looks like a dragonfly wearing a butterfly's antennae, and its camouflaged, debris-covered larvae ambush prey much like their close relatives the antlions. Read the guide →
Mammals VU Owston's Civet Chrotogale owstoni Owston's civet uses unusually long claws to dig earthworms directly out of the soil, a distinctively striped Southeast Asian civet now threatened by heavy snaring pressure. Read the guide →
Birds LC Oxpecker Buphagus africanus The oxpecker spends its life riding on big African mammals, feeding on their ticks, dead skin, earwax, and blood, and screeching an alarm when a predator nears. Read the guide →
Invertebrates NE Oyster Ostreidae An oyster is a rough-shelled bivalve that cements itself to a hard surface for life, filters up to 190 litres of water a day, builds reefs, and changes sex back and forth as it grows. Read the guide →
Fish LC Oyster Toadfish Opsanus tau The oyster toadfish is a warty, flat-headed bottom fish that hums like a foghorn using the fastest muscle known in any vertebrate. NASA flew it into space to study how the inner ear senses gravity. Read the guide →
Birds LC Oystercatcher Haematopus An oystercatcher uses its long, blade-like orange bill to pry open shellfish or hammer through a mussel shell, a technique young birds spend months learning from their parents. Read the guide →
Fish LC Ozark Sculpin Cottus hypselurus The Ozark sculpin lives only in cold, spring-fed Ozark streams, and was only recognized as its own species after genetic study separated it from a similar-looking relative. Read the guide →
Amphibians LC Ozark Zigzag Salamander Plethodon angusticlavius The Ozark zigzag salamander has no lungs at all, breathing entirely through its skin, and lays its eggs on land with no aquatic larval stage whatsoever. Read the guide →
Amphibians LC Pacific Chorus Frog Pseudacris regilla The 'ribbit' heard in nearly every Hollywood night scene is the Pacific chorus frog, recorded for decades in the hills above Los Angeles. Almost no other frog on Earth actually says 'ribbit'. Read the guide →
Amphibians LC Pacific Giant Salamander Dicamptodon A Pacific giant salamander is an amphibian of cold Pacific Northwest streams, one of the few salamanders with a voice, big enough to eat mice and snakes, and often keeping its gills for life. Read the guide →
Fish LC Pacific Halibut Hippoglossus stenolepis The Pacific halibut is the largest flatfish in the North Pacific, and like all flatfish it starts life symmetrical before one eye slowly migrates across its own skull. Read the guide →
Fish LC Pacific Leaping Blenny Alticus arnoldorum The Pacific leaping blenny is a fish that has essentially left the water, living on wave-splashed rocks above the tideline, breathing through its skin, and hopping between crevices with tail flicks. Read the guide →
Fish NT Pacific Sleeper Shark Somniosus pacificus The Pacific sleeper shark moves with such slow, sluggish grace that remains of giant squid have turned up in its stomach, a mystery given how much faster the squid itself can swim. Read the guide →
Mammals LC Pacific White-Sided Dolphin Lagenorhynchus obliquidens The Pacific white-sided dolphin is among the most acrobatic dolphins in the North Pacific, regularly performing spinning leaps, somersaults, and flips while travelling in large, boisterous groups. Read the guide →
Fish LC Pacu Piaractus brachypomus The pacu is a large Amazonian relative of the piranha with flat teeth uncannily like human molars. It cracks nuts and seeds fallen into flooded forest and scatters them like an underwater fruit bat. Read the guide →
Amphibians NT Paddle-Tail Newt Pachytriton spp. The paddle-tail newt spends nearly its entire life submerged in cold mountain streams, propelled by a flattened, paddle-shaped tail built for a lifestyle most newts never fully commit to. Read the guide →
Fish VU Paddlefish Polyodon spathula A paddlefish is an ancient, shark-shaped river fish with a paddle-shaped snout covered in electric sensors to detect plankton, and its Chinese relative was declared extinct in 2022. Read the guide →
Amphibians NE Paedophryne Amauensis Paedophryne amauensis Paedophryne amauensis of Papua New Guinea is the smallest known vertebrate, averaging 7.7 mm long, a frog that lives entirely in leaf litter, calls like an insect, and skips the tadpole stage. Read the guide →
Mammals LC Painted Bat Kerivoula picta The painted bat carries vivid orange-and-black fur and strikingly colourful wing membranes, making it one of the most visually distinctive bats in the world. Read the guide →
Birds LC Painted Bunting Passerina ciris The painted bunting is a small North American songbird whose male wears almost every colour a bird can produce at once, so vivid that early observers named it the nonpareil, without equal. Read the guide →
Fish LC Painted Comber Serranus scriba The painted comber is a small, boldly barred Mediterranean reef fish with blue markings around its head, and a hermaphrodite that can act as both male and female when it spawns. Read the guide →
Amphibians LC Painted Frog Discoglossus A painted frog is a small blotched frog of southwest Europe with a fixed disc tongue it cannot flick out, and its relative the Israel painted frog went extinct then reappeared as a living fossil. Read the guide →
Invertebrates LC Painted Lady Vanessa cardui The painted lady is found on every continent except Antarctica, and tracked migrations have shown individuals crossing entire deserts and seas long assumed to be far beyond a butterfly's reach. Read the guide →
Reptiles LC Painted Turtle Chrysemys picta The painted turtle is the most widespread native turtle in North America, a small basker with red-and-yellow trim whose hatchlings can survive being frozen almost solid through their first winter. Read the guide →
Invertebrates LC Painter's Mussel Unio pictorum The painter's mussel is an elongated freshwater mussel of European rivers and lakes whose shells were once used by artists to hold their pigments, and whose larvae travel on the gills of fish. Read the guide →
Mammals LC Pallas's Cat Otocolobus manul Pallas's cat is a small, extraordinarily fluffy wild cat of the Central Asian steppe, built low with flat-set ears for peering over rocks. Its coat is the longest of any cat. Read the guide →
Mammals LC Pallas's Long-tongued Bat Glossophaga soricina Pallas's long-tongued bat is a small, hovering nectar bat of the American tropics that laps up nectar with a brush-tipped tongue and pollinates many flowers. Read the guide →
Mammals LC Pallid Bat Antrozous pallidus The pallid bat hunts scorpions on the ground and is immune to their stings, snatching prey directly off the desert floor rather than catching insects in flight. Read the guide →
Fish EN Pallid Sturgeon Scaphirhynchus albus The pallid sturgeon may not reach sexual maturity until its twenties, and dam-driven habitat loss has made it one of the most endangered fish in North America. Read the guide →
Birds NT Palm Cockatoo Probosciger aterrimus The palm cockatoo is a large smoky-black parrot of New Guinea and northern Australia with a huge bill and red cheeks, and males drum on hollow trees with a shaped stick to mark their territory. Read the guide →
Amphibians LC Palmate Newt Lissotriton helveticus The palmate newt is the smallest newt in Britain and western Europe, a delicate amphibian whose breeding male grows black webs on his hind feet and a fine thread off the tip of his tail. Read the guide →
Mammals NT Pampas Cat Leopardus colocola The pampas cat shows an unusually variable coat pattern across its enormous range, so different from one region to another that populations were once mistaken for separate species. Read the guide →
Amphibians CR Panamanian Golden Frog Atelopus zeteki The Panamanian golden frog carries a nerve poison stronger than pufferfish toxin, and because rushing streams drown its calls it 'waves' its front legs to signal. It is now extinct in the wild. Read the guide →
Reptiles CR Pancake Tortoise Malacochersus tornieri The pancake tortoise of East Africa has a flat, thin, flexible shell full of gaps; rather than hide inside it, the tortoise runs for a rock crevice and wedges in where no predator can follow. Read the guide →
Fish LC Panda Corydoras Corydoras panda The panda corydoras carries bold black eye and tail patches recalling its mammalian namesake, a small catfish that prefers noticeably cooler water than most of its relatives. Read the guide →
Mammals CR Pangolin Manis javanica The pangolin is the only mammal covered in scales, a nocturnal ant-and-termite eater that rolls into an armoured ball when threatened — and the most trafficked wild mammal in the world. Read the guide →
Reptiles LC Panther Chameleon Furcifer pardalis The panther chameleon of Madagascar is the most vividly coloured chameleon, with skin that shifts by moving nanocrystals, eyes that swivel independently, and a tongue longer than its body. Read the guide →
Invertebrates LC Paper Wasp Polistes The paper wasp chews wood fibers into a pulp to build an open, umbrella-shaped nest, and a colony's queen is decided through direct physical dominance rather than any inherited rank. Read the guide →
Reptiles LC Paradise Flying Snake Chrysopelea paradisi The paradise flying snake flattens its body into a ribbon-like wing, leaps from a branch, and undulates through the air to glide up to 30 metres between trees. It is harmless to people. Read the guide →
Birds LC Paradise Jacamar Galbula dea The paradise jacamar carries unusually long, elegant tail streamers unlike any other jacamar species, its mostly black plumage shimmering with iridescent blue-green. Read the guide →
Birds LC Paradise Tanager Tangara chilensis The paradise tanager combines turquoise, black, red, yellow, and sky blue in a single bird, one of the most vividly multicoloured species on Earth. Read the guide →
Amphibians LC Paradox Frog Pseudis paradoxa The paradox frog of South America is famous for a strange life history — its tadpole grows to around 25 cm, three or four times the length of the small adult frog it eventually becomes. Read the guide →
Mammals NT Parma Wallaby Notamacropus parma The parma wallaby was presumed extinct for decades until a population turned up on a New Zealand island, only for the species to then be rediscovered back in mainland Australia. Read the guide →
Mammals LC Parnell's Mustached Bat Pteronotus parnellii Parnell's mustached bat uses long constant-frequency calls and adjusts them as it flies to detect the flutter of insect wings, a sophisticated echolocation system it shares with horseshoe bats. Read the guide →
Birds NE Parrot Psittaciformes A parrot is a bird with a hooked bill, a grasping foot with two toes forward and two back, and among the largest brains for its body size of any bird, which is why many can imitate speech. Read the guide →
Fish LC Parrotfish Scaridae Parrotfish scrape algae off coral reefs with a fused beak of teeth, grind the rock in their throats, and excrete it as fine white sand — a single fish can produce hundreds of kilograms a year. Read the guide →
Amphibians LC Parsley Frog Pelodytes A parsley frog is a small southwest-European frog flecked bright green as if dusted with chopped parsley, a good climber despite lacking toe pads, that often breeds in autumn as well as spring. Read the guide →
Reptiles NT Parson's Chameleon Calumma parsonii Parson's chameleon of Madagascar is among the largest chameleons in the world, a heavy, slow, turquoise-and-yellow giant whose eggs can take almost two years to hatch. Read the guide →
Mammals LC Parti-coloured Bat Vespertilio murinus The parti-coloured bat is a frosted-looking migratory bat of Eurasia whose males sing from cliffs and tall buildings in autumn to attract mates. Read the guide →
Birds EX Passenger Pigeon Ectopistes migratorius The passenger pigeon was once the most numerous bird in North America, in flocks of billions that darkened the sky for days. Commercial hunting and forest clearing wiped it out in about fifty years. Read the guide →
Amphibians EN Patagonia Frog Atelognathus patagonicus The Patagonia frog spends almost its entire life in a handful of cold Andean lakes, its restricted range now threatened by introduced trout that prey heavily on its tadpoles. Read the guide →
Fish LC Patagonian Blenny Eleginops maclovinus The Patagonian blenny is a common coastal fish of southern South America and the Falkland Islands, tolerating both salt and brackish water and supporting an important small-scale coastal fishery. Read the guide →
Birds LC Patagonian Canastero Asthenes patagonica The Patagonian canastero builds a distinctive domed stick nest across the arid steppe, a small ovenbird species that stays close to the sparse scrub vegetation it calls home. Read the guide →
Fish LC Patagonian Grenadier Macruronus magellanicus The Patagonian grenadier supports one of the few Southern Ocean fisheries with international sustainability certification, unlike several notothenioid relatives devastated by past overfishing. Read the guide →
Mammals LC Patagonian Hog-nosed Skunk Conepatus humboldtii The Patagonian hog-nosed skunk uses a long, flexible snout to root out insects and grubs from the soil, defending itself with the same powerful spray common to all skunk species. Read the guide →
Mammals NT Patagonian Mara Dolichotis patagonum The Patagonian mara looks and moves like a small deer despite being one of the largest rodents alive, monogamous pairs raising young in communal underground dens. Read the guide →
Birds LC Patagonian Mockingbird Mimus patagonicus The Patagonian mockingbird ranges across the arid steppe further south than its more widespread chalk-browed relative, sharing the same remarkable talent for mimicking other birds' songs. Read the guide →
Mammals LC Patagonian Opossum Lestodelphys halli The Patagonian opossum is the southernmost-ranging marsupial species anywhere in the Americas, a rarely observed hunter of small prey across the cold, arid Patagonian steppe. Read the guide →
Birds LC Patagonian Sierra-finch Phrygilus patagonicus The Patagonian sierra-finch is a small songbird of southern beech forest edges, favouring cooler, more forested habitat than several of its more open-country sierra-finch relatives. Read the guide →
Birds LC Patagonian Tinamou Tinamotis ingoufi The Patagonian tinamou is a ground-dwelling bird of the arid Patagonian steppe, relying on camouflage and a reluctance to fly rather than speed or altitude to avoid predators. Read the guide →
Fish NT Patagonian Toothfish Dissostichus eleginoides The Patagonian toothfish is marketed worldwide as Chilean sea bass, a rebranding that turned a once-obscure deep-water fish into one of the most commercially valuable species in the Southern Ocean. Read the guide →
Mammals DD Patagonian Weasel Lyncodon patagonicus The Patagonian weasel is so rarely observed that scientists still know very little about its basic behaviour, one of the least-studied carnivores anywhere in South America. Read the guide →
Birds LC Patagonian Yellow-Finch Sicalis lebruni The Patagonian yellow-finch forages in small flocks across the open steppe of southern Argentina and Chile, its yellow-olive plumage blending into dry grassland. Read the guide →
Mammals LC Patas Monkey Erythrocebus patas The patas monkey is the fastest primate on Earth, sprinting across open savanna at speeds few predators can match rather than fleeing into trees. Read the guide →
Reptiles LC Patch-Nosed Snake Salvadora spp. The patch-nosed snake carries an enlarged, upturned scale on its snout tip, used like a small shovel to dig through loose desert soil in pursuit of lizards and their eggs. Read the guide →
Invertebrates LC Patchwork Leafcutter Bee Megachile centuncularis The patchwork leafcutter bee is a solitary bee that cuts neat semicircles from rose and other leaves to line its nest cells in hollow stems and holes, and carries pollen on its belly. Read the guide →
Fish NE Payara Hydrolycus scomberoides The payara, or vampire fish, is a powerful Amazon predator with two long fangs in its lower jaw that slot into sockets in its skull and impale smaller fish, including piranhas, that it swallows whole. Read the guide →
Birds LC Peach-Faced Lovebird Agapornis roseicollis The peach-faced lovebird carries strips of nesting material tucked into its rump feathers rather than in its bill, an unusual transport method shared by only a handful of related lovebird species. Read the guide →
Fish LC Peacock Bass Cichla A peacock bass is a hard-striking South American cichlid, not a true bass, that is one of the top freshwater sport fish and a destructive invader where it has been introduced outside the Amazon. Read the guide →
Invertebrates LC Peacock Butterfly Aglais io The peacock butterfly flashes four huge eyespots and hisses by rubbing its wings together when disturbed, then hibernates as an adult in sheds, hollow trees, and woodpiles through the winter. Read the guide →
Fish LC Peacock Cichlid Aulonocara nyassae The peacock cichlid uses enlarged, sensory-lined cheek pores to detect prey hiding beneath sand, hunting by feel across Lake Malawi's open sandy floor rather than by sight alone. Read the guide →
Fish LC Peacock Flounder Bothus lunatus The peacock flounder starts life symmetrical, then one eye migrates across its skull so it can lie flat on the seabed. It can match a checkerboard in seconds. Read the guide →
Invertebrates LC Peacock Mantis Shrimp Odontodactylus scyllarus The peacock mantis shrimp throws the fastest punch in the animal kingdom, boiling the water around it, and sees with the most complex eyes known — 12 to 16 colour channels against a human's three. Read the guide →
Invertebrates NE Peacock Spider Maratus Peacock spiders are tiny Australian jumping spiders, most only 4-5 mm long. The male raises a vivid abdominal flap and dances for a female who will eat him if he gets it wrong. Read the guide →
Amphibians NT Peaks of Otter Salamander Plethodon hubrichti The Peaks of Otter salamander survives only on one small stretch of Virginia's Blue Ridge Mountains, making it one of the most narrowly restricted vertebrate species in North America. Read the guide →
Mammals LC Peale's Dolphin Lagenorhynchus australis Peale's dolphin is a fast, agile dolphin found along the rocky coastlines of southern South America, often seen riding the bow waves of boats navigating the channels near Cape Horn. Read the guide →
Invertebrates NE Peanut Worm Sipuncula The peanut worm can retract its feeding end inward until it shrinks into a plump, wrinkled shape resembling its namesake legume, a burrowing marine worm with no close relatives among segmented worms. Read the guide →
Invertebrates NE Peanut-head Bug Fulgora laternaria The peanut-head bug is a large tropical planthopper with a hollow, peanut-shaped growth on its head marked like a lizard's face. Folklore wrongly says its bite is deadly unless you quickly have sex. Read the guide →
Fish LC Pearl Dace Margariscus margarita The pearl dace tolerates some of the coldest, most oxygen-poor water any small minnow regularly survives in, thriving in boggy northern streams and beaver ponds many other fish species avoid entirely. Read the guide →
Fish LC Pearl Danio Danio albolineatus The pearl danio carries an iridescent pinkish-purple sheen across its body that shifts and shimmers like the surface of a pearl as the fish moves through the water. Read the guide →
Fish LC Pearl Gourami Trichopodus leerii The pearl gourami is covered in fine, pale speckling that catches the light like scattered pearls, one of the more peaceful and widely kept species in the entire gourami family. Read the guide →
Fish LC Pearlfish Carapidae The pearlfish lives inside the body cavity of a sea cucumber, entering tail-first through its host's rear end and sometimes feeding on its internal organs from within. Read the guide →
Amphibians VU Pedernales Mountain Salamander Eurycea pterophila The Pedernales mountain salamander survives only around a handful of spring-fed streams in central Texas, a fully aquatic species whose entire global range could be crossed on foot in an afternoon. Read the guide →
Fish LC Pejerrey Odontesthes bonariensis The pejerrey is a silvery South American fish so prized for sport fishing that it has been introduced to lakes on multiple continents far outside its native range. Read the guide →
Birds NE Pelican Pelecanidae A pelican is a huge water bird whose stretchy throat pouch holds more than its stomach, and it fishes by scooping in coordinated groups or, in the brown pelican, by plunge-diving from height. Read the guide →
Invertebrates LC Pencil Urchin Eucidaris The pencil urchin carries thick, blunt spines once literally used as writing pencils, a body plan so ancient that fossil relatives of the group date back hundreds of millions of years. Read the guide →
Birds NE Penguin Spheniscidae A penguin is a flightless seabird that flies underwater instead, its wings turned into stiff flippers, its bones made dense for diving, and its packed feathers and fat sealing out the cold ocean. Read the guide →
Invertebrates LC Peppered Moth Biston betularia The peppered moth is a night-flying moth famous as a textbook case of evolution, after a soot-dark form spread through industrial cities and then retreated once the air was cleaned. Read the guide →
Fish NE Perch Percidae A perch is a spiny-finned freshwater fish of the family Percidae, which includes the yellow and European perch, the walleye and zander, and the many tiny darters of North American streams. Read the guide →
Mammals EW Pere David's Deer Elaphurus davidianus Pere David's deer vanished from the wild in China over a century ago, surviving only in European deer parks before descendants were eventually returned to reestablish the species. Read the guide →
Birds LC Peregrine Falcon Falco peregrinus The peregrine falcon is the fastest animal on the planet, hitting nearly 390 km/h in a hunting dive. Learn how its body survives that speed and how it came back from near-extinction. Read the guide →
Reptiles LC Perentie Varanus giganteus The perentie is Australia's largest lizard and the fourth-largest in the world, over 2 metres long. It stands on its hind legs to scan the horizon and sprints down prey on two legs. Read the guide →
Invertebrates NE Periodical Cicada Magicicada septendecim Periodical cicadas spend 13 or 17 years underground as nymphs, then emerge by the billion in one synchronised week. The prime-number cycle appears to be a strategy to starve out predators. Read the guide →
Fish LC Permit Trachinotus falcatus The permit is a deep-bodied flats fish considered one of the toughest catches in saltwater fly fishing, spooking at the slightest disturbance while feeding in barely enough water to cover its back. Read the guide →
Birds EN Peruvian Diving-petrel Pelecanoides garnotii The Peruvian diving-petrel breeds along the desert coasts of Peru and Chile, flying underwater in pursuit of prey, but has declined sharply as guano mining destroys its nesting burrows. Read the guide →
Birds LC Phainopepla Phainopepla nitens The phainopepla depends almost entirely on desert mistletoe berries, and a single bird may defend the same berry-laden tree for months, passing the seeds unusually fast through its digestive system. Read the guide →
Amphibians NT Phantasmal Poison Frog Epipedobates anthonyi The phantasmal poison frog is a thumbnail-sized Ecuadorian frog whose skin contains epibatidine, a painkiller about 200 times stronger than morphine that inspired a new class of drug research. Read the guide →
Invertebrates NE Pharaoh Ant Monomorium pharaonis The pharaoh ant is a tiny yellow-brown ant that thrives in heated buildings worldwide, with many-queened colonies that split when disturbed and trails marked with a repellent "no entry" signal. Read the guide →
Reptiles CR Philippine Crocodile Crocodylus mindorensis The Philippine crocodile is a small freshwater crocodile found only in the Philippines, one of the rarest crocodilians on Earth, protected by villagers who are rewarded for guarding nests. Read the guide →
Birds CR Philippine Eagle Pithecophaga jefferyi The Philippine eagle is one of the largest and rarest eagles, standing a metre tall with a shaggy mane it raises into a crest. Fewer than 400 breeding pairs remain. Read the guide →
Mammals NT Philippine Tarsier Carlito syrichta The Philippine tarsier eats only live prey and can turn its head almost all the way around, compensating for eyes each larger than its own brain. Read the guide →
Fish LC Picasso Triggerfish Rhinecanthus aculeatus The Picasso triggerfish carries bold, geometric facial markings striking enough to earn its name, and is celebrated in Hawaii under a name so long it became a well-known tongue-twister. Read the guide →
Mammals NT Pichi Zaedyus pichiy The pichi is the only armadillo species known to hibernate, surviving cold Patagonian winters by slowing its body down completely underground until warmer weather returns. Read the guide →
Amphibians LC Pickerel Frog Lithobates palustris The pickerel frog is the only frog native to North America with skin toxic enough to matter, strong enough to kill other frogs shut in a bag with it and to make most snakes leave it alone. Read the guide →
Mammals LC Piebald Shrew Diplomesodon pulchellum The piebald shrew is one of the very few shrew species adapted to true desert, marked with a bold black-and-white pattern and equipped for digging through loose sand. Read the guide →
Birds LC Pied Kingfisher Ceryle rudis The pied kingfisher hunts by hovering in mid-air over open water before folding its wings and dropping straight down onto a fish, a technique most other kingfishers never use at all. Read the guide →
Mammals EN Pied Tamarin Saguinus bicolor The pied tamarin is an Endangered, bare-faced monkey found only around the city of Manaus in Brazil, where it survives in forest fragments and even in city parks and gardens. Read the guide →
Amphibians LC Pig Frog Lithobates grylio The pig frog is a large, almost fully aquatic frog of southeastern US marshes, named for its deep pig-like grunt, and it supplies most of the wild frog legs eaten in the United States. Read the guide →
Reptiles VU Pig-nosed Turtle Carettochelys insculpta The pig-nosed turtle is the only freshwater turtle with true flippers like a sea turtle, and it has a fleshy pig-like snout it uses as a snorkel. Its eggs hatch only when a flood arrives. Read the guide →
Birds NE Pigeon Columbidae A pigeon is a member of the dove family, a seed and fruit eater that feeds its young on milk made in the throat and navigates home over hundreds of kilometres; the dodo was a giant one. Read the guide →
Amphibians VU Pigeon Mountain Salamander Plethodon petraeus The Pigeon Mountain salamander is found nowhere on Earth outside a single Georgia mountain, discovered as recently as 1993 and still known almost entirely from the rocky outcrops of that one location. Read the guide →
Invertebrates LC Piglet Squid Helicocranchia pfefferi The piglet squid has a small, round, balloon-like body with tiny fins near the top, giving it an uncanny resemblance to a cartoon piglet as it hovers almost motionless in open water. Read the guide →
Fish NE Pike Esocidae A pike is a long, torpedo-shaped ambush predator of cool fresh water, holding still among weeds until prey drifts close, then striking in a burst so fast it is over before the prey reacts. Read the guide →
Birds LC Pileated Woodpecker Dryocopus pileatus The pileated woodpecker is a crow-sized red-crested bird that hammers rectangular holes deep into dead trees to reach carpenter ants, and its abandoned cavities house dozens of other forest species. Read the guide →
Invertebrates LC Pill Bug Armadillidium vulgare The pill bug is not an insect but a land crustacean, a relative of crabs and shrimp that breathes with gills, rolls into a ball when threatened, and quietly pulls heavy metals out of the soil. Read the guide →
Invertebrates NE Pill Millipede Glomerida and Sphaerotheriida A pill millipede rolls into a sealed ball when threatened, tucking its head and legs inside overlapping armour plates. It looks like a woodlouse 'pill bug' but is unrelated — convergent evolution. Read the guide →
Invertebrates CR Pillar Coral Dendrogyra cylindrus The pillar coral grows upward in tall, finger-like columns unlike the flatter shapes of most reef corals, its polyps left extended by day, a habit growing rare as the species nears extinction. Read the guide →
Mammals LC Pilot Whale Globicephala melas The pilot whale is one of the largest members of the dolphin family despite its name, a deep-diving squid hunter whose tight family bonds sometimes lead entire pods to strand together on beaches. Read the guide →
Fish NE Pilotfish Naucrates ductor The pilotfish swims alongside sharks, rays, and turtles in a tight escort, riding the pressure wave off a larger animal to save energy. Sailors once believed it guided lost sharks to food. Read the guide →
Birds LC Pin-Tailed Whydah Vidua macroura The male pin-tailed whydah grows tail feathers several times his own body length for the breeding season, then discards them, and raises none of his own chicks, laying eggs only in others' nests. Read the guide →
Amphibians NT Pine Barrens Treefrog Hyla andersonii The Pine Barrens treefrog carries a lavender-grey body set off by a bold dark stripe and bright orange flashes on the thighs, one of North America's most strikingly patterned treefrogs. Read the guide →
Birds LC Pine Grosbeak Pinicola enucleator The pine grosbeak is remarkably unafraid of people, a trusting nature shaped by a life spent in remote boreal forest with little human contact. Read the guide →
Birds LC Pine Warbler Setophaga pinus The pine warbler is one of the very few warblers that regularly eats seeds, letting it visit backyard feeders in winter when its insect-eating relatives have already left for the tropics. Read the guide →
Reptiles LC Pine Woods Snake Rhadinaea flavilata The pine woods snake spends nearly its life beneath leaf litter and rotting logs in southeastern pine forests, making it one of the least frequently observed native snakes despite being fairly common. Read the guide →
Amphibians LC Pine Woods Tree Frog Hyla femoralis The pine woods tree frog hides small yellow-orange spots on the underside of its hind legs, a marking invisible until the frog leaps, and calls in a rapid pattern like Morse code. Read the guide →
Fish LC Pineconefish Monocentris japonica The pineconefish is encased in large, ridged, plate-like scales that make it look like a swimming pinecone. Light organs on its jaw glow from luminous bacteria, acting as headlights for night hunting. Read the guide →
Mammals DD Pink Fairy Armadillo Chlamyphorus truncatus The pink fairy armadillo is the smallest armadillo alive, no longer than a hand, with a thin blush-pink shell attached only along the spine. It swims through desert sand and is almost never seen. Read the guide →
Fish LC Pink Salmon Oncorhynchus gorbuscha The pink salmon is the smallest and most abundant Pacific salmon, running on a two-year life cycle so precise that entire river populations return in either even or odd years but almost never both. Read the guide →
Invertebrates NE Pinktoe Tarantula Avicularia avicularia The pinktoe tarantula lives almost entirely in trees, gripping bark with pink-tipped feet and building silk retreats high above the rainforest floor rather than digging a burrow. Read the guide →
Birds VU Pinyon Jay Gymnorhinus cyanocephalus The pinyon jay caches tens of thousands of pine seeds each autumn and remembers many exact hiding spots months later, a memory feat tied to the survival of the pinyon pine woodland it depends on. Read the guide →
Fish LC Pipefish Syngnathidae A pipefish is a thin, tube-bodied relative of the seahorse that hides among seagrass and weed by mimicking it, and like the seahorse it is the male, not the female, that becomes pregnant. Read the guide →
Invertebrates LC Pipevine Swallowtail Battus philenor The pipevine swallowtail's caterpillar eats a toxic plant and keeps the poison for life, making the adult dangerous enough to eat that several unrelated butterflies copy its colour pattern. Read the guide →
Birds NT Piping Plover Charadrius melodus The piping plover nests directly on open sand, its speckled eggs and chicks nearly invisible against the beach, and it fakes a broken wing to lure predators away from the nest. Read the guide →
Birds LC Pipit Anthus spp. The pipit walks rather than hops across open ground, and many species climb high into the air to sing before parachuting back down on stiffened wings. Read the guide →
Fish NE Piranha Serrasalmidae A piranha is a deep-bodied South American fish with interlocking triangular teeth and a bite force among the strongest for its size of any animal, and most of its fearsome reputation is myth. Read the guide →
Fish LC Pirate Perch Aphredoderus sayanus The pirate perch is the only living member of its family, a fish whose vent migrates forward to sit beneath its throat as it matures, an arrangement found in no other North American freshwater fish. Read the guide →
Invertebrates NE Pistol Shrimp Alpheidae The pistol shrimp snaps one huge claw so fast it fires a bubble that briefly nears the sun's surface temperature, stunning prey with the shockwave. Colonies are among the loudest things in the sea. Read the guide →
Birds EN Pitt Shag Leucocarbo featherstoni The Pitt shag breeds only around New Zealand's Chatham Islands group, a distinct blue-eyed shag species separate from the nearby Chatham shag despite sharing much of the same small archipelago. Read the guide →
Birds LC Pitta Pittidae The pitta hides jewel-bright plumage of red, blue, and green on the forest floor, a shy, ground-hopping bird more often heard giving a sharp two-note whistle than actually seen among the shadows. Read the guide →
Reptiles LC Plain-Bellied Water Snake Nerodia erythrogaster The plain-bellied water snake carries a solid, unmarked belly that separates it from its more boldly patterned relatives, a wide-ranging species found across a broad range of wetland habitats. Read the guide →
Birds LC Plain-Brown Woodcreeper Dendrocincla fuliginosa The plain-brown woodcreeper dominates other woodcreepers at army ant swarms, its unmarked brown plumage a plain disguise for one of the rainforest's most successful ant-following birds. Read the guide →
Fish LC Plainfin Midshipman Porichthys notatus The plainfin midshipman is a Pacific fish that hums. Nesting males drone loudly for hours to attract females, and rows of light organs on the belly, like a uniform's buttons, give the fish its name. Read the guide →
Reptiles LC Plains Garter Snake Thamnophis radix The plains garter snake tolerates cooler climates than many of its relatives, carrying a bold orange stripe down a body that ranges across the open prairie of the central United States and Canada. Read the guide →
Fish LC Plains Killifish Fundulus zebrinus The plains killifish buries itself in loose, sandy streambeds to escape predators and extreme temperatures, a survival strategy suited to the wide, shallow, ever-shifting prairie rivers it calls home. Read the guide →
Amphibians LC Plains Leopard Frog Lithobates blairi The plains leopard frog produces a short, chuckling call quite unlike its close relatives, one of several look-alike leopard frog species spread across the central United States. Read the guide →
Mammals LC Plains Pocket Gopher Geomys bursarius The plains pocket gopher pushes excess soil out through side tunnels, leaving fan-shaped mounds across grassland that mark an entire hidden burrow system below. Read the guide →
Amphibians LC Plains Spadefoot Spea bombifrons The plains spadefoot is a burrowing prairie amphibian that spends most of its life a metre underground and races through its whole breeding cycle in the puddles left by a summer storm. Read the guide →
Mammals LC Plains Viscacha Lagostomus maximus The plains viscacha lives in large burrow colonies called vizcacheras, decorating the entrances with a habit of collecting bones, sticks, and other found objects. Read the guide →
Mammals NT Plains Zebra Equus quagga The plains zebra is the most common wild horse, famous for stripes no two animals share. Learn what the stripes are actually for, why zebras were never tamed, and how their herds work. Read the guide →
Birds CR Plains-wanderer Pedionomus torquatus The plains-wanderer looks like a small quail but is the sole survivor of an ancient lineage, ranking among the most evolutionarily distinct birds alive. It is Critically Endangered. Read the guide →
Invertebrates LC Planarian Tricladida A planarian is a flatworm that can be cut into dozens of pieces and regrow a complete, fully functional individual from nearly every fragment, including one that regrows a working brain from scratch. Read the guide →
Invertebrates LC Planthopper Fulgoroidea Some planthopper nymphs have literal interlocking mechanical gears built into their hind legs, a genuine gear mechanism found nowhere else in the animal kingdom. Read the guide →
Birds NT Plate-billed Mountain Toucan Andigena laminirostris The plate-billed mountain toucan carries a distinctive ridged plate along the base of its bill, a threatened Andean specialist found at higher elevations than most toucans. Read the guide →
Reptiles LC Plateau Striped Whiptail Aspidoscelis velox The plateau striped whiptail is another all-female, parthenogenetic species, laying unfertilized eggs that develop into exact genetic copies of the mother without any need for a male. Read the guide →
Reptiles LC Plated Lizard Gerrhosauridae A plated lizard is an African and Madagascan reptile covered in rows of bony-plated scales, giving it an armoured look similar to distantly related girdled lizards despite no close connection. Read the guide →
Fish LC Platy Xiphophorus maculatus A platy is a small, hardy, brightly coloured livebearer from Central America, one of the easiest of all aquarium fish, and a close relative of the swordtail with which it freely interbreeds. Read the guide →
Mammals NT Platypus Ornithorhynchus anatinus The platypus is a venomous, egg-laying mammal that hunts with its eyes shut, sensing prey by electric field. Learn how this Australian oddity works and why it is now Near Threatened. Read the guide →
Fish LC Plecostomus Hypostomus and relatives A plecostomus is a South American armoured catfish with a sucker mouth and bony plates, sold as an aquarium algae-eater, though it outgrows most tanks and, released, becomes an invasive pest. Read the guide →
Reptiles CR Ploughshare Tortoise Astrochelys yniphora The ploughshare tortoise is one of the rarest tortoises on Earth, with only a few hundred left in a single small region of Madagascar, identified by a forward-curving plate beneath its shell. Read the guide →
Birds LC Plumbeous Rail Pardirallus sanguinolentus The plumbeous rail moves secretively through dense marsh vegetation, its dark slate-grey plumage and bright red legs and bill base rarely seen despite the species' wide South American range. Read the guide →
Amphibians EN Poison Dart Frog Family Dendrobatidae Poison dart frogs wear bright warning colours and carry some of nature's most potent toxins — borrowed from their diet. Learn how the poison works and why captive frogs are harmless. Read the guide →
Mammals VU Polar Bear Ursus maritimus The polar bear is the largest land carnivore and a marine mammal that hunts seals from sea ice. Learn how it stays warm, why it needs the ice, and how warming threatens it. Read the guide →
Fish LC Pollack Pollachius pollachius The pollack is a streamlined, olive-gold, jut-jawed relative of the cod that hunts small fish over rocky reefs and wrecks of the north-eastern Atlantic and is a prized quarry of rod anglers. Read the guide →
Invertebrates LC Polyphemus Moth Antheraea polyphemus The Polyphemus moth carries a huge eyespot on each hindwing named for a one-eyed giant of Greek myth, flashed suddenly to startle a bird just long enough for the moth to escape. Read the guide →
Fish LC Pompano Trachinotus carolinus The pompano is a fast-swimming jack relative prized as one of the finest eating fish along the southeastern US coast, foraging the wash of sandy surf zones for buried prey. Read the guide →
Invertebrates NE Pompeii Worm Alvinella pompejana The Pompeii worm tolerates one of the widest temperature ranges of any known animal, with its head in cool water while its tail end can sit in water over 80 degrees Celsius near a hydrothermal vent. Read the guide →
Amphibians LC Pool Frog Pelophylax lessonae A pool frog is a small green water frog of Europe, and it was recognised as a genuine British native only after it went extinct there, and was then reintroduced from Sweden. Read the guide →
Fish VU Porbeagle Lamna nasus The porbeagle is a stout, fast, warm-bodied relative of the great white and mako that hunts fish and squid across the cool North Atlantic, and has been overfished to the edge of collapse. Read the guide →
Mammals LC Porcupine Hystricidae and Erethizontidae A porcupine is a large, slow rodent armoured with thousands of sharp, barbed quills that detach on contact and work their way inward, and it cannot throw them, contrary to a very old myth. Read the guide →
Fish LC Porcupinefish Diodontidae A porcupinefish swallows water to swell into a spiky ball twice its normal size, a slow-swimming reef fish that trades speed for one of the most effective last-resort defenses in the ocean. Read the guide →
Fish LC Port Jackson Shark Heterodontus portusjacksoni The Port Jackson shark is a blunt-headed Australian shark with a spine on each fin and crushing back teeth for shellfish. Females wedge spiral, screw-shaped egg cases into rock crevices. Read the guide →
Invertebrates NE Portia Spider Portia fimbriata Portia is a jumping spider that hunts other spiders by planning detour routes to attack from above and by plucking their webs to imitate trapped prey, adjusting the trick by trial and error. Read the guide →
Invertebrates NE Portuguese Man o' War Physalia physalis The Portuguese man o' war looks like a jellyfish but is not even one animal — it is a floating colony of four kinds of specialised organism that cannot survive apart, trailing long stinging tentacles. Read the guide →
Birds NE Potoo Nyctibiidae The potoo is a nocturnal insect-catcher of American forests that spends the day frozen upright on a broken branch, bill to the sky, so well disguised as a dead stump that people walk past it. Read the guide →
Mammals LC Potto Perodicticus potto The potto moves so deliberately through the canopy that it can go almost undetected for hours, defending itself instead with sharp bony spines along its neck. Read the guide →
Mammals LC Pousargues's Mongoose Dologale dybowskii Pousargues's mongoose is so poorly documented that basic details of its social structure and behaviour remain uncertain, a small Central African species known mainly from scattered records. Read the guide →
Fish LC Powder Blue Tang Acanthurus leucosternon The powder blue tang pairs a vivid sky-blue body with a black face mask, carrying a razor-sharp spine near its tail that gives the wider surgeonfish family its name. Read the guide →
Birds LC Prairie Falcon Falco mexicanus The prairie falcon nests on desert cliff ledges far from water and hunts ground squirrels across open range, an arid-country specialist among falcons that rarely needs to drink. Read the guide →
Reptiles LC Prairie Kingsnake Lampropeltis calligaster The prairie kingsnake spends much of its life underground hunting rodents, and its blotched juvenile pattern can fade to nearly solid brown by the time it reaches adulthood. Read the guide →
Reptiles LC Prairie Rattlesnake Crotalus viridis The prairie rattlesnake often shelters in burrow systems abandoned by prairie dogs rather than digging its own, a venomous predator woven directly into the Great Plains grassland ecosystem. Read the guide →
Reptiles LC Prairie Skink Plestiodon septentrionalis The prairie skink burrows through sandy tallgrass prairie soil by day, and its juveniles carry a bright blue tail that fades to a plainer colour as the lizard matures. Read the guide →
Mammals LC Prairie Vole Microtus ochrogaster The prairie vole is one of the few rodents that mates for life, a monogamous pair-bonding behaviour that has made it a leading model for neuroscience research. Read the guide →
Birds NT Prairie Warbler Setophaga discolor The prairie warbler is almost never found on a true prairie, favouring shrubby old fields, pine barrens, and mangroves instead, and constantly bobs its tail while foraging low in dense cover. Read the guide →
Invertebrates NE Praying Mantis Mantis religiosa The praying mantis is an ambush hunter that strikes in under 70 milliseconds, turns its head 180 degrees, and hears bats with a single ear. Learn how it hunts and the truth about sexual cannibalism. Read the guide →
Invertebrates LC Predatory Tunicate Megalodicopia hians The predatory tunicate abandoned filter feeding entirely, evolving a wide, hood-like mouth that snaps shut on small animals instead of straining plankton from passing water. Read the guide →
Mammals LC Prehensile-tailed Porcupine Coendou prehensilis The prehensile-tailed porcupine climbs rainforest trees at night with a gripping, bare-tipped tail, protected by sharp quills that it cannot throw. Read the guide →
Invertebrates NE Priapulid Worm Priapulus The priapulid worm has hardly changed since before the dinosaurs, an ambush predator that lurks in seafloor mud and lunges out with a spiny, invertible throat to seize passing prey. Read the guide →
Fish LC Prickly Sculpin Cottus asper The prickly sculpin is covered in small, rough prickles across much of its skin, a texture unusual among freshwater fish that gives the species its name and sets it apart from smoother relatives. Read the guide →
Invertebrates NE Privet Hawk-moth Sphinx ligustri The privet hawk-moth is one of Europe's largest moths, with a pink-and-black banded body and a huge green caterpillar striped with purple and tipped with a curved horn. Read the guide →
Mammals LC Proboscis Bat Rhynchonycteris naso The proboscis bat roosts in neat head-to-tail lines along branches over water, its long pointed nose and mottled fur helping it blend seamlessly into tree bark. Read the guide →
Mammals EN Proboscis Monkey Nasalis larvatus The male proboscis monkey carries a huge pendulous nose that amplifies his honking calls. It is also one of the very few primates that swims well, crossing rivers with webbed feet. Read the guide →
Invertebrates LC Promethea Moth Callosamia promethea The male promethea moth flies by day disguised as a foul-tasting swallowtail butterfly, while the female waits until dusk to release her scent instead. Read the guide →
Mammals LC Pronghorn Antilocapra americana The pronghorn is the fastest land animal in the Americas and Earth's best distance runner — built to escape a predator that went extinct 12,000 years ago. Learn about its speed and odd horns. Read the guide →
Birds LC Prothonotary Warbler Protonotaria citrea The prothonotary warbler is the only eastern warbler that nests inside tree cavities over water, a habit unusual enough among ground- and shrub-nesting warblers to earn it the nickname "swamp canary." Read the guide →
Birds VU Providence Petrel Pterodroma solandri The Providence petrel breeds on a handful of remote islands near Australia, its name recalling how starving Norfolk Island settlers were saved by an unexpected arrival of the birds. Read the guide →
Mammals EN Przewalski's Horse Equus ferus przewalskii Przewalski's horse is a stocky Mongolian wild horse that vanished from the wild in the 1960s and was returned to the steppe from zoo herds, though its ancestors may once have been domestic. Read the guide →
Invertebrates NE Pseudoscorpion Pseudoscorpiones The pseudoscorpion is a tiny arachnid with a scorpion's pincers but no tail and no sting, often found in old books, that spins silk from its jaws and hitches rides on larger insects. Read the guide →
Amphibians CR Puerto Rican Crested Toad Peltophryne lemur The Puerto Rican crested toad is the island's only native toad, once thought extinct for decades, and it now survives largely through sustained amphibian captive breeding. Read the guide →
Reptiles LC Puff Adder Bitis arietans The puff adder is a thick, sluggish, superbly camouflaged African viper that kills more people than any other snake on the continent, because it lies still on paths instead of moving away. Read the guide →
Birds LC Puffbird Bucconidae A puffbird perches motionless for long stretches, feathers fluffed into a round, puffy shape, before launching a sudden strike at a passing insect and battering the prey against a branch. Read the guide →
Fish NT Pufferfish Takifugu rubripes The pufferfish inflates into a spiky ball by gulping water, and its organs hold tetrodotoxin, a nerve poison with no antidote. In Japan, chefs train for years to serve it as fugu. Read the guide →
Fish LC Pugnose Minnow Opsopoeodus emiliae The pugnose minnow has a small, upturned mouth angled almost straight up, an adaptation suited to picking food from just below the water's surface rather than the bottom most minnows target. Read the guide →
Amphibians LC Pumpkin Toadlet Brachycephalus ephippium The pumpkin toadlet is a thumbnail-sized, blazing orange frog whose bones glow under UV light through its thin skin. It is so small its balance organs no longer work, so it cannot land a jump. Read the guide →
Fish LC Pumpkinseed Lepomis gibbosus The pumpkinseed carries a bright red spot at the tip of its gill flap unlike most other sunfish, a small, vividly patterned panfish often the very first fish caught by children learning to fish. Read the guide →
Birds LC Puna Ibis Plegadis ridgwayi The puna ibis breeds on high-altitude Andean wetlands, its glossy dark plumage catching an iridescent sheen as it wades through shallow water probing for invertebrates. Read the guide →
Fish VU Pupfish Cyprinodon spp. The pupfish survives in isolated desert springs hot and salty enough to kill most other fish, an extremophile relative whose species can be found nowhere else but a single tiny pool. Read the guide →
Invertebrates LC Purple Emperor Apatura iris The purple emperor is a rare, treetop-dwelling woodland butterfly whose males flash an iridescent purple sheen, and which feeds on tree sap and honeydew rather than flower nectar. Read the guide →
Amphibians EN Purple Frog Nasikabatrachus sahyadrensis The purple frog spends all but two weeks of the year buried underground, surfacing only in the monsoon to breed. Its lineage split from all other frogs around 120 million years ago. Read the guide →
Birds LC Purple Gallinule Porphyrio martinica The purple gallinule wears an almost impossibly vivid combination of purple, blue, and green, walking across lily pads on long yellow toes that spread its weight evenly enough to avoid sinking. Read the guide →
Invertebrates LC Purple Hairstreak Favonius quercus The purple hairstreak is a small oak-canopy butterfly with a purple sheen on its upper wings, which spends almost its whole life high in the treetops feeding on honeydew rather than nectar. Read the guide →
Birds LC Purple Heron Ardea purpurea The purple heron is a slimmer, more secretive relative of the grey heron, favouring dense reed beds over open water and blending its chestnut and slate plumage into marsh vegetation. Read the guide →
Invertebrates LC Purple Sea Urchin Strongylocentrotus purpuratus The purple sea urchin can turn a healthy kelp forest into a barren field of bare rock when its natural predators disappear, grazing algae down using a complex mouth called Aristotle's lantern. Read the guide →
Birds LC Purple Swamphen Porphyrio porphyrio The purple swamphen wields a massive red bill capable of tearing apart tough reed stems, using an oversized foot to hold food steady while it feeds like a bird with hands. Read the guide →
Birds LC Purple-throated Fruitcrow Querula purpurata The purple-throated fruitcrow lives in cooperative social groups, males showing an iridescent purple throat patch against otherwise glossy black plumage. Read the guide →
Invertebrates LC Puss Caterpillar Megalopyge opercularis The puss caterpillar looks soft enough to pet, covered in fur resembling a tiny cat, but hidden beneath that fuzzy coat are venomous spines rated among the most painful insect stings in North America. Read the guide →
Invertebrates NE Puss Moth Cerura vinula The puss moth is a fluffy white-and-grey European moth whose green caterpillar rears up with a red false face and whip-like tails and sprays formic acid at attackers. Read the guide →
Fish LC Puye Galaxias maculatus The puye migrates between rivers and the sea across an extraordinary Southern Hemisphere range, found in South America, New Zealand, and Australia despite its small size and short lifespan. Read the guide →
Reptiles LC Pygmy Chameleon Rhampholeon spp. The pygmy chameleon is among the smallest reptiles on Earth, small enough to perch on a fingertip, spending its life camouflaged as a dead leaf on the forest floor rather than climbing. Read the guide →
Mammals EN Pygmy Hippo Choeropsis liberiensis The pygmy hippo is a shy, nocturnal forest animal of West Africa that weighs about a tenth as much as the common hippo, lives mostly on land near water, and is now endangered. Read the guide →
Mammals CR Pygmy Hog Porcula salvania The pygmy hog is the smallest and rarest wild pig in the world, a Critically Endangered grassland animal of Assam in India that builds a grass nest and has been bred in captivity and reintroduced. Read the guide →
Reptiles CR Pygmy Leaf Chameleon Brookesia nana The pygmy leaf chameleon of northern Madagascar may be the smallest reptile in the world. An adult male measures about 22 millimetres from nose to tail tip and fits on a fingertip. Read the guide →
Fish EN Pygmy Madtom Noturus stanauli The pygmy madtom is one of the smallest catfish in North America, a tiny, venomous-spined fish restricted to a couple of Tennessee River tributaries and considered one of the continent's rarest fish. Read the guide →
Mammals LC Pygmy Marmoset Cebuella pygmaea The pygmy marmoset is the smallest monkey in the world — an adult fits in a human palm — and it lives by gnawing hundreds of holes in tree trunks and lapping the sap that seeps out. Read the guide →
Mammals NT Pygmy Rabbit Brachylagus idahoensis The pygmy rabbit is the smallest rabbit species in North America and the only one that digs its own burrow, surviving almost entirely on the sagebrush that gives it both food and shelter. Read the guide →
Reptiles LC Pygmy Rattlesnake Sistrurus miliarius The pygmy rattlesnake's rattle is so tiny it often buzzes more like an insect than a warning, a quiet trait shared by one of the smallest rattlesnake species in North America. Read the guide →
Mammals LC Pygmy Right Whale Caperea marginata The pygmy right whale is the smallest and most poorly understood baleen whale in the world, rarely seen alive and known mostly from a handful of strandings across the Southern Hemisphere. Read the guide →
Amphibians LC Pygmy Salamander Desmognathus wrighti The pygmy salamander is one of the world's smallest salamanders, a lungless sprite of high Appalachian spruce forest that climbs trees at night and has no aquatic larval stage. Read the guide →
Fish NE Pygmy Seahorse Hippocampus bargibanti The pygmy seahorse is barely larger than a fingernail and camouflages so precisely against its host coral that it went unnoticed by science until one was found attached to a collected specimen. Read the guide →
Reptiles LC Pygmy Short-Horned Lizard Phrynosoma douglasii The pygmy short-horned lizard tolerates cooler, higher conditions than almost any other horned lizard, and gives birth to live young rather than laying eggs, suited to its short growing season. Read the guide →
Mammals VU Pygmy Slow Loris Nycticebus pygmaeus The pygmy slow loris delivers a toxic bite by combining its own saliva with a gland secretion near its elbow, one of the few venomous mammals and the smallest of the slow loris species. Read the guide →
Mammals LC Pygmy Sperm Whale Kogia breviceps The pygmy sperm whale releases a cloud of reddish-brown fluid when startled, a smokescreen that helps this small, elusive deep-diving relative of the sperm whale disappear from potential predators. Read the guide →
Mammals CR Pygmy Three-toed Sloth Bradypus pygmaeus The pygmy three-toed sloth is a Critically Endangered dwarf sloth found only on a single small island off Panama, where it lives in mangroves and swims between them. Read the guide →
Invertebrates NE Pyjama Squid Sepioloidea lineolata The pyjama squid carries bold brown and white stripes and is not actually a true squid, a small bobtail squid relative whose flesh is toxic enough to deter most predators. Read the guide →
Amphibians NT Pyrenean Newt Calotriton asper The Pyrenean newt is a mountain amphibian so adapted to cold, fast-flowing streams that its eggs are laid individually under stones in the current rather than in a still pond. Read the guide →
Invertebrates NE Pyrosome Pyrosoma spp. The pyrosome is not one animal but thousands of tiny clones fused into a single glowing, tube-shaped colony, sometimes large enough for a diver to swim straight through its hollow centre. Read the guide →
Birds LC Pyrrhuloxia Cardinalis sinuatus The pyrrhuloxia looks like a pale, grey desert version of the familiar northern cardinal, sharing the same crest and stout bill but adapted to a far drier, harsher landscape. Read the guide →
Reptiles NE Python Pythonidae A python is a non-venomous constrictor that kills by stopping its prey's blood flow, swallows animals wider than its own head, and in one species grows longer than any other snake on Earth. Read the guide →
Invertebrates NE Quagga Mussel Dreissena rostriformis bugensis The quagga mussel is a small, striped freshwater mussel from Ukraine that has invaded the Great Lakes and western Europe, carpeting the bottom, clogging pipes, and outcompeting the zebra mussel. Read the guide →
Invertebrates LC Quahog Mercenaria mercenaria The quahog can live for centuries, among the longest-lived non-colonial animals known, and its purple-tinged shell was once carefully crafted into wampum used as currency and in ceremony. Read the guide →
Invertebrates EN Queen Alexandra's Birdwing Ornithoptera alexandrae Queen Alexandra's birdwing is the largest butterfly in the world, with females reaching a wingspan of up to 30 centimetres, found only in a small area of rainforest in Papua New Guinea. Read the guide →
Fish LC Queen Angelfish Holacanthus ciliaris The queen angelfish wears a dark, electric-blue-ringed spot on its forehead like a crown, a blue-and-yellow Caribbean reef fish that feeds mostly on sponges. Read the guide →
Invertebrates LC Queen Butterfly Danaus gilippus The queen butterfly is a close relative of the monarch sharing the same toxic milkweed diet, but males also release pheromones from specialised wing scales during courtship, a trait the monarch lacks. Read the guide →
Invertebrates NE Queen Scallop Aequipecten opercularis The queen scallop, or queenie, is a small, colourful, fast-swimming scallop of north-eastern Atlantic sandy seabeds that clap-jets away from starfish and is trawled for the table. Read the guide →
Reptiles LC Queen Snake Regina septemvittata The queen snake is a North American water snake with one of the most specialised diets of any snake on Earth, feeding almost exclusively on freshly moulted crayfish too soft-shelled to fight back. Read the guide →
Invertebrates LC Question Mark Butterfly Polygonia interrogationis The question mark butterfly carries a tiny silver punctuation mark on the underside of each hindwing, a curved dash and a dot that together resemble a question mark and give the species its name. Read the guide →
Birds NT Quetzal Pharomachrus A quetzal is an iridescent green-and-crimson cloud-forest bird of the American tropics, sacred to the Maya and Aztec, the national bird and currency of Guatemala, and said to die if kept in a cage. Read the guide →
Fish LC Quillback Carpiodes cyprinus The quillback carries a tall, sharply pointed dorsal fin whose leading ray extends into a long, quill-like filament, a feature striking enough to give the species its common name. Read the guide →
Mammals VU Quokka Setonix brachyurus The quokka is a cat-sized wallaby whose relaxed face made it a viral "smiling" animal. It survives on a few predator-free islands off Western Australia and barely needs to drink. Read the guide →
Mammals LC Rabbit Oryctolagus cuniculus and relatives A rabbit is a long-eared burrowing herbivore that breeds fast and re-eats its own soft droppings, and the European species is both the ancestor of every pet breed and a notorious invasive pest. Read the guide →
Mammals LC Raccoon Procyon lotor The raccoon is a masked, ring-tailed omnivore with hands sensitive enough to identify food by touch alone. It has thrived alongside people and spread from North America across Europe and Japan. Read the guide →
Mammals LC Raccoon Dog Nyctereutes procyonoides The raccoon dog is a true canid that looks strikingly like a raccoon, one of the only dog family members capable of true hibernation, spending the coldest winter months in a den rather than active. Read the guide →
Reptiles LC Racer Coluber constrictor A racer is a fast, slender, alert North American snake that hunts by day with its head raised above the grass, and despite the name constrictor it usually just pins prey and swallows it alive. Read the guide →
Reptiles CR Radiated Tortoise Astrochelys radiata The radiated tortoise wears a starburst shell of bright yellow lines radiating from a dark centre. Endemic to Madagascar, it can live over a century but is Critically Endangered from poaching. Read the guide →
Invertebrates NE Railroad Worm Phrixothrix hirtus The railroad worm is the larva of a South American beetle that glows like a lit train, with rows of green lights down its body and, uniquely among land animals, a pair of red lights on its head. Read the guide →
Amphibians NE Rain Frog Brevicipitidae A rain frog is a round, short-legged, permanently frowning African frog that lives underground, cannot swim or hop, glues to its mate for weeks, and skips the tadpole stage entirely. Read the guide →
Reptiles LC Rainbow Agama Agama agama The rainbow agama is a widespread African lizard whose dominant males flash a bright blue body and orange-red head, doing push-ups on rooftops and rocks as they lead their groups. Read the guide →
Fish LC Rainbow Darter Etheostoma caeruleum The rainbow darter's breeding males burst into vivid blue, orange, and red, a small, colourful stream fish that rivals many tropical species despite living entirely in cool North American creeks. Read the guide →
Invertebrates NE Rainbow Dung Beetle Phanaeus vindex The rainbow dung beetle shimmers in iridescent red, green, and gold, a vividly coloured relative of the dung-rolling scarabs that digs its dung underground instead of rolling it. Read the guide →
Birds LC Rainbow Lorikeet Trichoglossus moluccanus The rainbow lorikeet is a loud, brilliantly coloured Australian parrot with a brush-tipped tongue built to mop nectar and pollen from flowers, a diet that shapes almost everything about how it lives. Read the guide →
Fish EN Rainbow Shark Epalzeorhynchos frenatum The rainbow shark is not a true shark but a shark-shaped freshwater minnow, now considered Endangered in the wild in Thailand despite remaining common and widely bred for aquariums. Read the guide →
Reptiles LC Rainbow Snake Farancia erytrogramma A rainbow snake is a large, iridescent, non-venomous American snake that specialises almost entirely in hunting eels, and it is so secretive that even where common it is rarely ever seen. Read the guide →
Invertebrates NE Rainbow Stag Beetle Phalacrognathus muelleri The rainbow stag beetle shimmers in iridescent green, gold, and copper, widely considered one of the most beautifully coloured beetles found anywhere in the world. Read the guide →
Fish LC Rainbow Trout Oncorhynchus mykiss The rainbow trout is a cold-water fish of western North America, farmed and stocked into about a hundred countries; its sea-run form, the steelhead, is the same species after a life at sea. Read the guide →
Fish LC Rainbow Wrasse Coris julis The rainbow wrasse is a slender, colourful Mediterranean reef fish in which drab orange-striped females change into green-blue males with a zigzag orange stripe, and which dives into sand at night. Read the guide →
Mammals LC Rakali Hydromys chrysogaster The rakali is Australia's semi-aquatic native water-rat, a white-tailed hunter of freshwater crayfish, mussels, and fish that is at home in rivers, lakes, and estuaries. Read the guide →
Fish LC Ram Cichlid Mikrogeophagus ramirezi The ram cichlid packs iridescent blue, yellow, and red into a body barely five centimetres long, a popular dwarf cichlid that is noticeably more sensitive to water quality than most. Read the guide →
Invertebrates NE Ramshorn Snail Planorbella and relatives The ramshorn snail carries a flattened, coiled shell resembling a ram's horn, breathing air through a simple lung that lets it survive in low-oxygen water where many snails cannot. Read the guide →
Fish LC Rasbora Rasbora and Trigonostigma A rasbora is a small, peaceful, schooling Southeast Asian cyprinid fish, and the harlequin rasbora, with its orange body and black triangular patch, is one of the most popular aquarium fish. Read the guide →
Reptiles LC Rat Snake Pantherophis and relatives A rat snake is a non-venomous constrictor of Northern Hemisphere farmland and forest that hunts rodents and birds, climbs well, and is one of the most useful snakes to have around a barn. Read the guide →
Reptiles NE Rattlesnake Crotalus and Sistrurus A rattlesnake is a New World pit viper that grows a warning rattle from hollow segments of shed skin, senses the body heat of prey through facial pits, and strikes from ambush in a split second. Read the guide →
Fish NE Ray Batoidea A ray is a flattened relative of the shark that swims by rippling or flapping its wing-like fins, with mouth and gills underneath and eyes on top, and many carry a venomous tail spine. Read the guide →
Invertebrates LC Razor Clam Ensis directus The razor clam can vanish straight down into wet sand within seconds of being uncovered, among the fastest-digging bivalves known, its long narrow shell shaped like an old-fashioned straight razor. Read the guide →
Reptiles LC Razorback Musk Turtle Sternotherus carinatus The razorback musk turtle carries a distinctly high, sharply keeled shell unlike the flatter shells of its musk turtle relatives, a shape pronounced enough to give the species its common name. Read the guide →
Birds LC Razorbill Alca torda The razorbill dives deep beneath the North Atlantic using its wings to swim, and it is the closest living relative of the extinct great auk, with a deep, blade-like bill of its own. Read the guide →
Invertebrates LC Red Admiral Vanessa atalanta The red admiral undertakes long-distance migrations similar to the monarch butterfly, though far less studied, with individuals sometimes travelling hundreds of kilometres in a single season. Read the guide →
Invertebrates EN Red Coral Corallium rubrum The red coral is a branching Mediterranean coral with a hard crimson skeleton prized for jewellery for thousands of years, which grows extremely slowly in dim caves and is now endangered. Read the guide →
Birds LC Red Crossbill Loxia curvirostra The red crossbill has a bill with tips that cross rather than meet, an odd-looking adaptation that lets it pry open unopened conifer cones and extract seeds no straight-billed bird could reach. Read the guide →
Mammals LC Red Deer Cervus elaphus The red deer stag announces the autumn rutting season with a deep, roaring bugle, backing up its call with a rack of branching antlers regrown every single year. Read the guide →
Reptiles NT Red Diamond Rattlesnake Crotalus ruber The red diamond rattlesnake is famously mild-mannered for a rattlesnake, often reluctant to rattle or strike even when disturbed at close range. Read the guide →
Fish LC Red Drum Sciaenops ocellatus The red drum carries a black eyespot near its tail that tricks predators into striking the wrong end, and males drum by vibrating muscles against their own swim bladder. Read the guide →
Mammals LC Red Fox Vulpes vulpes The red fox is the most widespread wild carnivore on Earth, at home in forests, deserts, and city centres alike. Learn how it hunts by the Earth's magnetic field and why it thrives around people. Read the guide →
Fish VU Red Grouper Epinephelus morio The red grouper actively digs and maintains pits in the sea floor, an engineering habit that creates shelter used by dozens of other reef species, making this one fish a genuine ecosystem builder. Read the guide →
Fish CR Red Handfish Thymichthys politus The red handfish walks the seafloor on hand-shaped fins instead of swimming, and with only a few dozen known survivors in one tiny patch of Tasmanian reef, it's among the rarest fish alive. Read the guide →
Amphibians EN Red Hills Salamander Phaeognathus hubrichti The Red Hills salamander is Alabama's state amphibian, a large lungless salamander that never enters water and spends its whole life in a burrow dug into steep forested ravine slopes. Read the guide →
Birds LC Red Junglefowl Gallus gallus The red junglefowl is a wild pheasant of Southeast Asian forests and the main wild ancestor of the domestic chicken, the most numerous bird on Earth, with tens of billions alive at any moment. Read the guide →
Mammals LC Red Kangaroo Osphranter rufus The red kangaroo is the largest marsupial alive, built to bounce across Australia's dry interior. Learn how hopping saves energy, how the pouch works, and why females can pause a pregnancy. Read the guide →
Invertebrates LC Red King Crab Paralithodes camtschaticus The red king crab can span nearly two metres across its outstretched legs, a commercially prized giant that is actually more closely related to hermit crabs than to true crabs. Read the guide →
Birds NT Red Knot Calidris canutus rufa The red knot times its migration to arrive at Delaware Bay during the exact few weeks horseshoe crabs come ashore to spawn, refuelling almost entirely on their eggs before continuing on to the Arctic. Read the guide →
Fish LC Red Lionfish Pterois volitans The red lionfish is a striped Indo-Pacific reef fish armed with venomous spines. Released into the Atlantic by the aquarium trade, it has become one of the most damaging marine invasions on record. Read the guide →
Invertebrates LC Red Mason Bee Osmia bicornis The red mason bee is a gentle solitary bee of European gardens and orchards that nests in holes sealed with mud and is a highly effective pollinator of apple and pear blossom in spring. Read the guide →
Invertebrates LC Red Milkweed Beetle Tetraopes tetraophthalmus The red milkweed beetle carries a scientific name meaning "four eyes," each compound eye split in half by the base of an antenna, an adaptation found across its whole milkweed-specialist genus. Read the guide →
Fish LC Red Mullet Mullus surmuletus The red mullet, or surmullet, is a pink-red, stripe-flanked bottom fish with two long chin barbels that probe the sand for worms and crabs, prized as food since Roman times. Read the guide →
Mammals EN Red Panda Ailurus fulgens The red panda is not a panda and not a raccoon — it is the sole survivor of its own family, a cat-sized bamboo eater with a false thumb. Learn how it lives in the Himalaya and why it is Endangered. Read the guide →
Mammals LC Red River Hog Potamochoerus porcus The red river hog is a bright reddish-orange wild pig of West and Central African rainforest and swamps, with white face markings, long tufted ears, and a nocturnal habit of rooting for food. Read the guide →
Mammals EN Red Ruffed Lemur Varecia rubra The red ruffed lemur has one of the loudest calls of any primate, audible over a kilometre through the rainforest, and gives birth to litters of twins or triplets in a leaf nest. Read the guide →
Amphibians LC Red Salamander Pseudotriton ruber The red salamander is a bright coral-red, black-spotted lungless salamander of eastern US springs. Its colour mimics the genuinely toxic red eft so predators leave it alone. Read the guide →
Fish LC Red Snapper Lutjanus campechanus The red snapper can live for more than 50 years and grows slowly around artificial reefs and oil rigs, a longevity that has made fishery management a genuinely contentious issue in the Gulf of Mexico. Read the guide →
Reptiles LC Red Tegu Salvator rufescens The red tegu can raise its own body temperature above the surrounding air during breeding season, a rare form of warm-bloodedness for this large reddish South American lizard. Read the guide →
Invertebrates NE Red Velvet Mite Trombidiidae The red velvet mite emerges from the soil in large numbers after heavy rain, its bright red, velvety body among the largest and most visible mites found anywhere. Read the guide →
Invertebrates NE Red Wood Ant Formica rufa The red wood ant builds metre-high mounds of pine needles in European forests, housing hundreds of thousands of workers that spray formic acid, farm aphids, and protect the trees around them. Read the guide →
Fish LC Red Zebra Cichlid Maylandia estherae The red zebra cichlid is often more orange than red, since its natural colouring varies enormously between individuals, sexes, and different rocky stretches of Lake Malawi. Read the guide →
Birds LC Red-and-yellow Barbet Trachyphonus erythrocephalus The red-and-yellow barbet nests inside active termite mounds across East African dry bush, one of the most vividly coloured members of an already colourful family. Read the guide →
Amphibians LC Red-backed Salamander Plethodon cinereus The red-backed salamander has no lungs and breathes through its skin. It is so abundant in eastern North American forests that its total weight can exceed that of all the birds and mammals combined. Read the guide →
Reptiles LC Red-bellied Black Snake Pseudechis porphyriacus The red-bellied black snake is a glossy, shy Australian snake with bright red flanks and belly that swims well, eats frogs and other snakes, and has evolved some resistance to cane toad toxin. Read the guide →
Mammals VU Red-bellied Lemur Eulemur rubriventer The red-bellied lemur is a Vulnerable, monogamous lemur of eastern Madagascar's rainforests that is active by day and night and spreads the seeds of the fruit it eats. Read the guide →
Amphibians LC Red-Bellied Newt Taricha rivularis The red-bellied newt carries a vivid orange-red belly as a warning that its skin contains the same potent toxin found in some of its more famous newt relatives. Read the guide →
Fish LC Red-Bellied Piranha Pygocentrus nattereri The red-bellied piranha is a South American river fish with interlocking razor teeth and a fearsome reputation that outruns the facts. It shoals for safety, scavenges widely, and rarely bites people. Read the guide →
Reptiles LC Red-Bellied Snake Storeria occipitomaculata The red-bellied snake feeds almost entirely on slugs, and when frightened some individuals curl back their upper lip in a strange, nervous-looking grin rather than trying to strike. Read the guide →
Mammals LC Red-Bellied Squirrel Sciurus aureogaster The red-bellied squirrel displays such wide coat colour variation that individuals can look unrecognisable to each other, a widespread Mexican tree squirrel now also established in Florida. Read the guide →
Birds LC Red-Bellied Woodpecker Melanerpes carolinus The red-bellied woodpecker's namesake belly patch is so faint it is rarely visible, making its bright red cap the far more reliable way to identify one. Read the guide →
Birds LC Red-Billed Chough Pyrrhocorax pyrrhocorax The red-billed chough rides mountain and coastal updrafts with a level of aerobatic skill unusual even among crows, its curved red bill probing turf for insects between astonishing rolls and dives. Read the guide →
Birds LC Red-billed Quelea Quelea quelea The red-billed quelea is the most numerous wild bird on Earth, an African weaver that flies in flocks of millions and strips grain fields so thoroughly it is called the feathered locust. Read the guide →
Birds LC Red-Breasted Nuthatch Sitta canadensis The red-breasted nuthatch daubs sticky conifer resin around its nest entrance and then flies straight in without touching the sides, using the mess to deter predators it has evolved to avoid itself. Read the guide →
Birds LC Red-capped Manakin Ceratopipra mentalis The red-capped manakin performs a rapid backward sliding shuffle across a branch during courtship, a movement so similar to the human moonwalk that it is often compared to the dance move directly. Read the guide →
Birds NT Red-cockaded Woodpecker Dryobates borealis The red-cockaded woodpecker excavates its nest cavity in a living tree, drilling small wells around the entrance that ooze sticky resin to keep climbing snakes away. Read the guide →
Reptiles LC Red-eared Slider Trachemys scripta elegans The red-eared slider is the world's most popular pet turtle and one of its most invasive reptiles — released former pets now breed on every continent but Antarctica, outcompeting native turtles. Read the guide →
Amphibians LC Red-Eyed Tree Frog Agalychnis callidryas The red-eyed tree frog isn't poisonous — it survives by hiding green all day and flashing shock colours to escape. Learn its startle trick and the eggs that hatch early to dodge snakes. Read the guide →
Birds LC Red-Eyed Vireo Vireo olivaceus The red-eyed vireo sings from dawn until dusk with barely a pause, and a single male has been recorded delivering more than 20,000 short song phrases in a single day. Read the guide →
Mammals VU Red-Fronted Gazelle Eudorcas rufifrons The red-fronted gazelle carries a reddish band running down its face and along its flanks, a poorly studied Sahel-region gazelle scattered thinly across semi-arid West and Central Africa. Read the guide →
Birds NT Red-Headed Woodpecker Melanerpes erythrocephalus The red-headed woodpecker catches insects in midair as readily as it drills into wood, and it caches extra food in bark crevices, sometimes covering the stash with a scrap of wood. Read the guide →
Birds LC Red-Legged Partridge Alectoris rufa The red-legged partridge has spread well beyond its native Iberian range through deliberate introduction, though hybridisation with introduced chukars now threatens its genetic purity. Read the guide →
Fish LC Red-lipped Batfish Ogcocephalus darwini The red-lipped batfish has bright red lips and walks across the seafloor on modified fin rays instead of swimming, using a small lure on its head to draw prey close. Read the guide →
Mammals LC Red-Necked Wallaby Notamacropus rufogriseus The red-necked wallaby carries a reddish patch across its shoulders and has established wild breeding populations far outside Australia, from New Zealand to England's Peak District. Read the guide →
Mammals CR Red-Shanked Douc Pygathrix nemaeus The red-shanked douc wears one of the most vividly multicoloured coats of any primate, a pattern striking enough to earn it the nickname costumed ape. Read the guide →
Birds LC Red-Shouldered Hawk Buteo lineatus The red-shouldered hawk hunts from within dense forest rather than open sky, unusual for its family, and its loud call is so distinctive that blue jays are known to mimic it. Read the guide →
Amphibians LC Red-spotted Toad Anaxyrus punctatus The red-spotted toad is a small desert amphibian covered in warty, red-tipped tubercles rather than the large glands of most toads, and it can breed in rock pools barely large enough to hold water. Read the guide →
Invertebrates LC Red-tailed Bumblebee Bombus lapidarius The red-tailed bumblebee is a coal-black bumblebee with a bright red-orange tail, a common garden and meadow species that nests underground and is parasitised by the cuckoo bumblebee. Read the guide →
Birds LC Red-tailed Hawk Buteo jamaicensis The red-tailed hawk is North America's most common large hawk, the big brown raptor on every highway fence post, and the source of the scream that Hollywood dubs over nearly every eagle on screen. Read the guide →
Mammals LC Red-tailed Monkey Cercopithecus ascanius The red-tailed monkey is a Central African guenon with a white heart-shaped nose patch and a coppery tail that often travels in mixed troops with other forest monkeys. Read the guide →
Birds LC Red-winged Blackbird Agelaius phoeniceus The red-winged blackbird, one of North America's most abundant birds, is a black marsh bird whose red shoulder patches are a badge it can flash to warn off rivals or hide to pass unseen. Read the guide →
Invertebrates NE Redback Spider Latrodectus hasselti The redback spider is Australia's black widow, a small glossy black spider with a red back stripe that builds sticky trap-line webs in sheds and gardens. Its bite causes hours of escalating pain. Read the guide →
Fish LC Redbreast Sunfish Lepomis auritus The redbreast sunfish favours flowing streams and rivers more than the still water most of its sunfish relatives prefer, and breeding males flush a vivid orange-red across the breast. Read the guide →
Birds NT Reddish Egret Egretta rufescens The reddish egret hunts like no other heron, staggering and spinning as it chases fish across shallow coastal flats in one of the most erratic feeding displays in the bird world. Read the guide →
Fish LC Redear Sunfish Lepomis microlophus The redear sunfish carries specialised crushing teeth in its throat built specifically for cracking snail shells, a diet distinctive enough among sunfish to earn it the nickname shellcracker. Read the guide →
Fish LC Redeye Bass Micropterus coosae The redeye bass is restricted to clear, rocky upland streams in the southern Appalachians, a smaller, more stream-adapted relative of the largemouth and smallmouth bass with a strikingly red iris. Read the guide →
Fish LC Redline Darter Etheostoma rufilineatum The redline darter's breeding males develop thin red streaks running down the body and bright turquoise fins, a combination that makes it one of the more colorful small fish of Appalachian streams. Read the guide →
Fish NT Redside Dace Clinostomus elongatus The redside dace leaps clear out of the water to snatch flying insects just above the surface, a hunting technique unusual among small minnows and made possible by its unusually large, upturned mouth. Read the guide →
Fish LC Redtail Catfish Phractocephalus hemioliopterus The redtail catfish grows over a metre long with a distinctive reddish-orange tail, an opportunistic Amazon basin predator popular with aquarium keepers despite its eventual size. Read the guide →
Fish CR Redtail Shark Epalzeorhynchos bicolor The redtail shark was believed extinct in the wild for decades, surviving only in aquariums worldwide, until a small wild population was eventually rediscovered in Thailand. Read the guide →
Amphibians NE Reed Frog Hyperoliidae A reed frog is a small, often brilliantly coloured African tree frog that clings to reeds and grass stems above water, calls in loud night choruses, and in some species can change sex as an adult. Read the guide →
Fish LC Reef Stonefish Synanceia verrucosa The reef stonefish is the most venomous fish in the world — 13 spines loaded with a toxin that causes agonising pain and can kill. It looks exactly like an encrusted rock on the reef floor. Read the guide →
Birds VU Reeves's Pheasant Syrmaticus reevesii Reeves's pheasant grows the longest tail feathers of any pheasant species, trailing plumes that can stretch well over a metre behind a single bird. Read the guide →
Fish LC Regal Angelfish Pygoplites diacanthus The regal angelfish wears bold orange-and-white vertical bands above a yellow tail, a shy, sponge-eating reef fish that is notoriously difficult to keep alive in captivity. Read the guide →
Invertebrates NT Regal Fritillary Argynnis idalia The regal fritillary has vanished from most of its range east of the Mississippi as tallgrass prairie disappeared, leaving it dependent on violets found only in increasingly rare undisturbed prairie. Read the guide →
Reptiles LC Regal Horned Lizard Phrynosoma solare The regal horned lizard is the largest horned lizard, a flat, spiky desert reptile that eats stinging harvester ants and, when a coyote grabs it, squirts a jet of foul-tasting blood from its eye. Read the guide →
Invertebrates LC Regal Moth Citheronia regalis The regal moth's caterpillar, nicknamed the hickory horned devil, grows into one of the largest and most alarming-looking larvae in North America despite being entirely harmless. Read the guide →
Mammals VU Reindeer Rangifer tarandus Reindeer and caribou are the same species — the only deer in which females also grow antlers, a large mammal that sees ultraviolet light, and the animal behind the longest land migration on Earth. Read the guide →
Amphibians VU Relict Leopard Frog Lithobates onca The relict leopard frog was believed extinct for decades before a small population was rediscovered near Lake Mead, one of the rarest amphibians in North America, clinging on in a few desert springs. Read the guide →
Amphibians VU Relictual Slender Salamander Batrachoseps relictus The relictual slender salamander survives only in a handful of isolated Sierra Nevada foothill sites, a scattered remnant of a range that was once likely far more continuous. Read the guide →
Invertebrates NE Remipede Remipedia The remipede is a blind, venomous crustacean found only in flooded coastal caves connected to the sea, swimming upside down through total darkness and injecting prey with paralysing venom. Read the guide →
Fish LC Remora Echeneidae A remora rides on sharks, rays, turtles and whales using a flat ridged sucker on its head, a dorsal fin turned into a suction pad. It eats its host's scraps and pulls off only by sliding forward. Read the guide →
Birds NT Resplendent Quetzal Pharomachrus mocinno The resplendent quetzal is a shimmering green-and-crimson cloud-forest bird whose breeding males trail metre-long tail plumes. Sacred to the Maya and Aztec, it is Guatemala's national bird. Read the guide →
Reptiles LC Reticulated Banded Gecko Coleonyx reticulatus The reticulated banded gecko lives only in a narrow part of Big Bend, Texas, a nocturnal desert specialist named for the fine, net-like pattern spreading across its skin as it matures. Read the guide →
Amphibians LC Reticulated Glass Frog Hyalinobatrachium valerioi The reticulated glass frog has skin so transparent on its belly you can see its beating heart. The father guards the egg clutches on leaves over a stream, and his translucent body helps hide them. Read the guide →
Reptiles LC Reticulated Python Malayopython reticulatus The reticulated python is the longest snake in the world, a non-venomous constrictor that swims between islands and lives alongside people across Southeast Asia. Learn how it hunts and breeds. Read the guide →
Amphibians DD Reticulated Siren Siren reticulata The reticulated siren was only formally described in 2018, one of the largest new vertebrate species named in the United States in decades, despite a striking net-like pattern. Read the guide →
Birds NT Rhea Rhea A rhea is a large flightless ratite of the South American plains, the biggest bird in the Americas, in which one male incubates the eggs of a whole harem and raises the chicks alone. Read the guide →
Invertebrates NE Rhinoceros Beetle Dynastinae Rhinoceros beetles are among the strongest animals on Earth for their size, carrying many times their own weight, and males use their curved horns to pry rivals off a female or a feeding site. Read the guide →
Birds VU Rhinoceros Hornbill Buceros rhinoceros The rhinoceros hornbill carries a huge upswept orange casque on its bill, coloured by preen oil it rubs on. The female seals herself in a tree hollow for months while the male feeds her. Read the guide →
Reptiles EN Rhinoceros Iguana Cyclura cornuta The rhinoceros iguana is a large, heavy lizard of Hispaniola, named for the blunt horn-like growths on adult males' snouts. It can live over 50 years and depends on captive breeding and safe islands. Read the guide →
Reptiles LC Rhinoceros Viper Bitis nasicornis The rhinoceros viper is patterned in bold geometric blocks of blue, green, yellow, and black, with soft horn-like scales on its nose. It has among the longest fangs of any African snake. Read the guide →
Fish LC Ribbon Eel Rhinomuraena quadra The ribbon eel is a slender, fan-nosed moray that changes colour and sex as it grows, from black as a juvenile to electric blue as a male and bright yellow as a female. Read the guide →
Mammals LC Ribbon Seal Histriophoca fasciata The ribbon seal displays bold bands of pale colour wrapped around a dark body, one of the most strikingly patterned seals in the world, spending nearly its life scattered across drifting sea ice. Read the guide →
Reptiles LC Ribbon Snake Thamnophis sauritus The ribbon snake stays close enough to water to escape into it at the first sign of danger, a slender garter snake relative that hunts pond and marsh edges rather than open fields. Read the guide →
Invertebrates LC Ribbon Worm Nemertea A ribbon worm hunts by firing a sticky, sometimes toxin-coated proboscis out of its own head, and one species, the bootlace worm, may be the longest animal ever recorded, stretching past 55 metres. Read the guide →
Amphibians NT Rich Mountain Salamander Plethodon ouachitae The Rich Mountain salamander lends its scientific species name to the entire Ouachita Mountains, a lungless amphibian confined to a narrow stretch of ridge straddling the Arkansas-Oklahoma border. Read the guide →
Mammals LC Richardson's Ground Squirrel Urocitellus richardsonii Richardson's ground squirrel stands upright on the northern prairie to watch for predators and flicks its tail as it moves, giving it the nickname flickertail. Read the guide →
Reptiles LC Ridge-Nosed Rattlesnake Crotalus willardi The ridge-nosed rattlesnake is the official state reptile of Arizona, a small mountain specialist restricted to a handful of forested sky-island peaks separated by inhospitable desert lowlands. Read the guide →
Birds LC Riflebird Ptiloris A male riflebird transforms into a flattened black fan tipped with iridescent color, swiveling his head side to side in one of the most striking courtship displays of any bird-of-paradise. Read the guide →
Reptiles EN Rim Rock Crowned Snake Tantilla oolitica The rim rock crowned snake survives only in a narrow strip of limestone habitat in southern Florida, one of the most range-restricted snakes in the US and increasingly squeezed by urban development. Read the guide →
Birds LC Ring-billed Gull Larus delawarensis The ring-billed gull is one of the most familiar gulls in North America, recognisable by the neat black ring around its yellow bill and just as at home in a parking lot as on a lakeshore. Read the guide →
Birds LC Ring-Necked Pheasant Phasianus colchicus The ring-necked pheasant is native to Asia but has been introduced so widely as a game bird that most people encountering one today have no idea it started life half a world away. Read the guide →
Reptiles LC Ring-necked Snake Diadophis punctatus The ring-necked snake is a small secretive snake of North America with a slate back, a bright collar, and a yellow-to-red belly it flashes by coiling its tail into a corkscrew when cornered. Read the guide →
Mammals EN Ring-Tailed Lemur Lemur catta The ring-tailed lemur is the most recognisable of Madagascar's lemurs — a ground-loving primate that sunbathes in a lotus pose, is led by females, and holds "stink fights" with its scented tail. Read the guide →
Mammals LC Ring-Tailed Vontsira Galidia elegans The ring-tailed vontsira is Madagascar's most commonly seen native carnivore, an active daytime hunter belonging to the same island-exclusive family as the fossa and fanaloka. Read the guide →
Amphibians LC Ringed Caecilian Siphonops annulatus The ringed caecilian is a limbless, near-blind burrowing amphibian that looks like a large earthworm and whose young peel and eat their mother's skin. It may be the first venomous amphibian. Read the guide →
Birds LC Ringed Kingfisher Megaceryle torquata The ringed kingfisher is the largest kingfisher found anywhere in the Americas, a chunky, loud-calling hunter whose rattling cry often announces its presence along a riverbank before it is ever seen. Read the guide →
Amphibians LC Ringed Salamander Ambystoma annulatum The ringed salamander breaks from nearly every other mole salamander by breeding in autumn instead of spring, emerging from underground burrows just as the first cool rains of fall begin to fall. Read the guide →
Mammals LC Ringed Seal Pusa hispida The ringed seal carves its own breathing holes through thick Arctic sea ice with sharp claws, the primary prey of polar bears and a species whose survival is closely tied to that sea ice disappearing. Read the guide →
Invertebrates LC Ringlet Aphantopus hyperantus The ringlet is a velvety dark-brown butterfly of damp grassland and woodland rides, named for the yellow-ringed eyespots on its underside, and happy to fly in dull or drizzly weather. Read the guide →
Mammals LC Ringtail Bassariscus astutus The ringtail can rotate its hind feet nearly 180 degrees, allowing it to descend cliffs and narrow rock crevices head-first, a nocturnal raccoon relative once kept by miners to control camp rodents. Read the guide →
Reptiles LC Rinkhals Hemachatus haemachatus The rinkhals is a southern African spitting snake that is not a true cobra, with a hood, white throat bands, live young, and a habit of playing dead when threatened. Read the guide →
Amphibians LC Rio Grande Chirping Frog Eleutherodactylus cystignathoides The Rio Grande chirping frog skips the tadpole stage entirely, hatching directly into a tiny froglet, and has hitchhiked in nursery plants far beyond its native range. Read the guide →
Amphibians LC Rio Grande Leopard Frog Lithobates berlandieri The Rio Grande leopard frog tolerates warmer, more arid conditions than most leopard frog relatives, thriving in irrigation canals and stock tanks across otherwise dry border country. Read the guide →
Mammals LC Risso's Dolphin Grampus griseus Risso's dolphin is covered in pale scars accumulated over a lifetime, a squid hunter whose body grows progressively whiter with age as scratches from prey and social interaction pile up on its skin. Read the guide →
Fish LC River Chub Nocomis micropogon The male river chub builds a nest mound of thousands of pebbles carried one at a time in his mouth, a structure so attractive to other fish that several minnow species rely on it to spawn. Read the guide →
Reptiles LC River Cooter Pseudemys concinna The river cooter is one of the few reptiles known to communicate with its mouth completely underwater, using a face-to-face vibrating claw display that plays out entirely below the surface. Read the guide →
Amphibians LC River Frog Lithobates heckscheri The river frog is a big, dark, wrinkly frog of southeastern swamps and blackwater rivers, named for a deep snoring growl and known for playing dead when it is picked up. Read the guide →
Fish LC River Lamprey Lampetra fluviatilis The river lamprey is a jawless, eel-like fish that lives as a larva in river silt, feeds on other fish in estuaries as a parasite, and returns to rivers to spawn in autumn and spring before dying. Read the guide →
Fish LC River Redhorse Moxostoma carinatum The river redhorse has unusually large, molar-like teeth in its throat capable of crushing snail and mussel shells whole, a feeding tool more powerful than most of its redhorse relatives possess. Read the guide →
Mammals CR Riverine Rabbit Bunolagus monticolus The riverine rabbit ranks among the most endangered mammals on Earth, confined to a small, fragmented strip of seasonal riverbank vegetation in South Africa's Karoo region. Read the guide →
Fish LC Roach Rutilus rutilus The roach is a silvery, red-finned carp relative, probably the commonest freshwater fish across much of Europe, and the fish generations of anglers have caught first. Read the guide →
Birds LC Roadrunner Geococcyx A roadrunner is a large ground-dwelling cuckoo of the American southwest that would rather run than fly and hunts lizards, insects, and small rattlesnakes across the desert. Read the guide →
Mammals LC Roan Antelope Hippotragus equinus The roan antelope is one of the largest antelope in Africa, a horse-like grazer with a black-and-white facial mask and backward-curving ridged horns present on both sexes. Read the guide →
Fish VU Roanoke Bass Ambloplites cavifrons The Roanoke bass survives naturally in only a handful of Virginia and North Carolina rivers, a close relative of the widespread rock bass now increasingly displaced by that same relative. Read the guide →
Invertebrates LC Robber Fly Asilidae The robber fly ambushes prey mid-flight and injects enzymes that liquefy its victim from the inside, a bristly-faced aerial predator capable of overpowering insects considerably larger than itself. Read the guide →
Birds LC Robin Turdus migratorius and Erithacus rubecula A robin is one of two unrelated red-breasted songbirds sharing the name — the large American robin, a lawn-worm hunter, and the small round European robin, a fierce Christmas-card fixture. Read the guide →
Mammals LC Roborovski Hamster Phodopus roborovskii The Roborovski hamster is the smallest of the pet hamsters, a quick, sandy-coated desert dweller with white eyebrow spots and no stripe down its back. Read the guide →
Fish LC Rock Bass Ambloplites rupestris The rock bass gets its alternate name "redeye" from a distinctly reddish iris, an aggressive, rocky-habitat sunfish relative that will strike lures meant for far larger predatory fish. Read the guide →
Fish LC Rock Goby Gobius paganellus The rock goby is a stocky, mottled little fish of north-eastern Atlantic rocky shores that clings to stones with a sucker made of fused pelvic fins and guards its eggs in a crevice. Read the guide →
Mammals LC Rock Hyrax Procavia capensis The rock hyrax looks like a fat guinea pig, but its closest living relatives are elephants and manatees. It has tiny tusks and sweaty rubber feet for gripping rock. Read the guide →
Invertebrates LC Rock Louse Ligia spp. The rock louse darts across intertidal rocks fast enough to startle beachgoers, a marine isopod that spends its life at the boundary between land and sea without ever fully committing to either. Read the guide →
Reptiles LC Rock Monitor Varanus albigularis The rock monitor, or white-throated monitor, is a stocky, short-snouted African lizard of savanna and rocky country that feeds on snails, insects, eggs, and carrion and hisses loudly when cornered. Read the guide →
Birds NT Rock Partridge Alectoris graeca The rock partridge scrambles across steep alpine slopes of southern Europe, a close relative of the chukar so similar that the two species can and do interbreed where their ranges meet. Read the guide →
Birds LC Rock Pigeon Columba livia The rock pigeon was the first bird humans domesticated, carried messages through two world wars, and can navigate home over hundreds of kilometres using magnetism, smell, the sun, and infrasound. Read the guide →
Reptiles LC Rock Rattlesnake Crotalus lepidus The rock rattlesnake's banded pattern shifts in tone to match the exact colour of the local rock it lives among, making an already small, cryptic snake even harder to spot. Read the guide →
Birds LC Rock Shag Phalacrocorax magellanicus The rock shag breeds along the rocky coastlines of southern South America and the Falkland Islands, a different genus entirely from the blue-eyed shags of the New Zealand subantarctic. Read the guide →
Amphibians LC Rocket Frog Litoria nasuta A rocket frog is a slender, pointy-nosed Australian tree frog with enormously long hind legs that can jump about fifty times its body length, among the best jumps relative to size of any frog. Read the guide →
Fish NT Rockfish Sebastes A rockfish is a slow-growing bottom dweller that includes some of the longest-lived fish on Earth, with certain species confirmed to survive well over a century in cold Pacific waters. Read the guide →
Amphibians LC Rocky Mountain Tailed Frog Ascaphus montanus The Rocky Mountain tailed frog's "tail" is actually a unique copulatory organ, making it the only North American frog that fertilizes its eggs internally rather than in open water. Read the guide →
Mammals EN Rodrigues Flying Fox Pteropus rodricensis The Rodrigues flying fox is an Endangered fruit bat found only on Rodrigues Island, whose numbers fell below a hundred before conservation work brought it back to many thousands. Read the guide →
Mammals LC Roe Deer Capreolus capreolus The roe deer delays the start of pregnancy for months after mating, a small, territorial European deer whose embryo simply pauses its development until conditions are right for birth in spring. Read the guide →
Invertebrates LC Roesel's Bush-cricket Metrioptera roeselii Roesel's bush-cricket is a brown, green-edged bush-cricket of rough grassland whose continuous, buzzing, electric song has carried it northwards across Britain as the climate has warmed. Read the guide →
Birds LC Rook Corvus frugilegus The rook is a sociable European crow of farmland, told from a carrion crow by the bare greyish skin around the base of its pale bill and by its habit of nesting in noisy treetop colonies. Read the guide →
Invertebrates NE Rose Chafer Cetonia aurata The rose chafer is a shining metallic green beetle that feeds on flowers in sunshine and flies with its wing cases closed, while its grubs live in rotting wood and compost. Read the guide →
Reptiles LC Rose-Bellied Lizard Sceloporus variabilis The rose-bellied lizard reaches the northern edge of its range in southern Texas, common and abundant across most of its distribution but considerably harder to find the farther north one travels. Read the guide →
Birds LC Rose-Breasted Grosbeak Pheucticus ludovicianus The rose-breasted grosbeak carries a triangular splash of red across its chest so bold that early observers likened it to a wound, a striking songbird whose bill belies its melodic, warbling song. Read the guide →
Birds LC Rose-throated Becard Pachyramphus aglaiae The rose-throated becard shows a small rose-pink throat patch on otherwise grey-and-pink males, building a large hanging nest from the southwestern United States through Central America. Read the guide →
Birds LC Roseate Spoonbill Platalea ajaja The roseate spoonbill feeds by swinging its flat, spoon-shaped bill through shallow water, snapping shut the instant it touches food. Its pink plumage comes entirely from pigments in its prey. Read the guide →
Birds LC Roseate Tern Sterna dougallii The roseate tern takes its name from a faint pink blush across its breast during the breeding season, a delicate colour that fades quickly and pairs with unusually long tail streamers. Read the guide →
Invertebrates NE Rosemary Beetle Chrysolina americana The rosemary beetle is a small, iridescent green and purple-striped leaf beetle from southern Europe that eats rosemary, lavender, sage, and thyme, and has spread across southern England. Read the guide →
Mammals LC Ross Seal Ommatophoca rossii The Ross seal has unusually large eyes and a habit of arching its neck and inflating its throat to produce loud, warbling calls, spending most of its life alone amid Antarctic pack ice. Read the guide →
Reptiles LC Rosy Boa Lichanura trivirgata A rosy boa is a small, slow, gentle desert snake of the American Southwest, one of only two boas native to the United States, and a hardy, long-lived favourite as a first pet snake. Read the guide →
Invertebrates LC Rosy Maple Moth Dryocampa rubicunda The rosy maple moth displays bright pink and yellow so vivid it is often mistaken for something tropical, despite being a common species found across ordinary maple woodland in eastern North America. Read the guide →
Invertebrates LC Rosy Wolf Snail Euglandina rosea The rosy wolf snail hunts and eats other snails by trailing their slime, and its deliberate introduction to control a pest species instead drove several native Pacific island snails to extinction. Read the guide →
Birds LC Rosy-billed Pochard Netta peposaca The rosy-billed pochard is identified by a swollen, bright rosy-red knob at the base of the male's bill, a diving duck common across southern South American wetlands. Read the guide →
Fish LC Rosyface Shiner Notropis rubellus The rosyface shiner's breeding males flush a vivid rosy-red wash across the head and body, a seasonal display bright enough to stand out clearly even among a large, fast-moving school. Read the guide →
Reptiles CR Roti Island Snake-necked Turtle Chelodina mccordi The Roti Island snake-necked turtle is a freshwater turtle with an extraordinarily long neck, found naturally only on one small Indonesian island and nearly wiped out by collecting for the pet trade. Read the guide →
Invertebrates LC Rotifer Rotifera A rotifer is a microscopic animal whose crown of beating cilia looks like a spinning wheel, and some species can dry out completely for years and revive within minutes once rewetted. Read the guide →
Reptiles LC Rough Earth Snake Haldea striatula The rough earth snake carries keeled, ridged scales unlike its smooth-scaled relative, a tiny burrower that spends its life working through loose soil in search of earthworms and soft-bodied insects. Read the guide →
Reptiles LC Rough Green Snake Opheodrys aestivus The rough green snake is a slender, tree-climbing serpent whose keeled scales and green colour let it move through leafy branches almost invisibly, often mistaken for a vine swaying in the breeze. Read the guide →
Birds LC Rough-Legged Hawk Buteo lagopus The rough-legged hawk breeds on Arctic tundra and hunts by hovering in place over open ground, its legs feathered all the way to the toes against the cold. Read the guide →
Amphibians LC Rough-skinned Newt Taricha granulosa The rough-skinned newt carries enough tetrodotoxin in its skin to kill several adults, and one person died after swallowing one on a dare. Only one predator, a local garter snake, can eat it. Read the guide →
Mammals LC Rough-Toothed Dolphin Steno bredanensis The rough-toothed dolphin has a smooth, sloping forehead blending into its beak with no clear crease, a feature setting it apart from nearly every other dolphin with an unusually reptilian profile. Read the guide →
Fish NT Roughskin Dogfish Centroscymnus owstonii The roughskin dogfish spends its life far below sunlight, covered in coarse, sandpaper-like skin and equipped with light organs along its belly to hide its silhouette from predators below. Read the guide →
Reptiles LC Round-Tailed Horned Lizard Phrynosoma modestum The round-tailed horned lizard lacks the flattened, teardrop body of most other horned lizards, carrying instead a rounder, less spined build that lets it blend into pale, gravelly desert ground. Read the guide →
Reptiles LC Roundtail Horned Lizard Phrynosoma modestum The roundtail horned lizard carries such blunt, reduced horns that its head looks almost smooth, relying on pale, gravel-matching camouflage and stillness rather than spines to survive. Read the guide →
Invertebrates NE Roundworm Nematoda The roundworm may be the most numerous animal on Earth, with free-living and parasitic species found in nearly every habitat, and one tiny species mapped down to every single cell. Read the guide →
Fish LC Royal Gramma Gramma loreto The royal gramma splits its body into a vivid violet front half and bright yellow rear half, often swimming upside down against the ceiling of a sheltered Caribbean cave. Read the guide →
Birds NT Royal Penguin Eudyptes schlegeli The royal penguin breeds almost nowhere else on Earth except a single remote sub-Antarctic island group, where it gathers in colonies of well over a million birds crowned with a pale golden crest. Read the guide →
Birds LC Royal Tern Thalasseus maximus The royal tern is one of the largest terns in the world, carrying a heavy orange bill and a shaggy black crest that fades to a patchy, streaked forehead once the breeding season ends. Read the guide →
Reptiles LC Rubber Boa Charina bottae The rubber boa is a small, blunt-tailed North American boa with loose, wrinkled skin that looks and feels like rubber, one of the gentlest snakes alive and among the most cold-tolerant. Read the guide →
Amphibians LC Rubber Eel Typhlonectes natans The rubber eel is not an eel but a limbless aquatic amphibian, a caecilian. It is nearly blind, and the female's young feed inside her by scraping a nutrient-rich lining off her oviduct. Read the guide →
Invertebrates NE Ruby-tailed Wasp Chrysis ignita The ruby-tailed wasp is a small, metallic blue-green and ruby-red cuckoo wasp that slips into the nests of mason bees and potter wasps to lay its eggs, and curls into a ball when threatened. Read the guide →
Birds LC Ruby-Throated Hummingbird Archilochus colubris The ruby-throated hummingbird weighs about as much as a penny, beats its wings 50 times a second, and crosses the Gulf of Mexico non-stop — a 800-kilometre flight over open water. Read the guide →
Birds LC Ruby-topaz Hummingbird Chrysolampis mosquitus The ruby-topaz hummingbird flashes an iridescent ruby crown and golden-topaz throat that can appear dark until the light catches it at just the right angle. Read the guide →
Fish LC Rudd Scardinius erythrophthalmus The rudd is a golden-bronze carp relative with blazing red fins and an upturned mouth, a surface-feeding fish of still and slow waters across Europe that readily hybridises with roach and bream. Read the guide →
Birds LC Ruddy Kingfisher Halcyon coromanda The ruddy kingfisher glows a deep reddish-purple across nearly its entire body, a forest-dwelling hunter whose distinctive whistled call carries through Asian woodlands. Read the guide →
Mammals LC Ruddy Mongoose Urva smithii The ruddy mongoose carries a distinctive black-tipped tail, a reddish-coated forest species of southern India and Sri Lanka that ranks among the larger mongooses found in the region. Read the guide →
Birds LC Ruddy Turnstone Arenaria interpres The ruddy turnstone flips over stones, shells, and seaweed with a short, stout, upturned bill to expose hidden prey, a foraging trick distinctive enough to give the species its common name. Read the guide →
Birds NT Ruddy-headed Goose Chloephaga rubidiceps The ruddy-headed goose has collapsed on the South American mainland due to introduced predators, while a separate population on the predator-free Falkland Islands remains comparatively secure. Read the guide →
Birds LC Ruff Calidris pugnax The ruff is a wading bird with three fixed kinds of male, set by one block of genes. Most fight over a lek, some hang around as pale satellites, and a rare few disguise themselves as females. Read the guide →
Fish LC Ruffe Gymnocephalus cernua The ruffe is a small, spiny perch relative of European lakes and rivers with a single prickly dorsal fin and sensory pits on its head, and a successful invader in the Great Lakes of North America. Read the guide →
Mammals LC Rufous Bettong Aepyprymnus rufescens The rufous bettong digs up underground fungi each night, using a prehensile tail to carry bundles of grass back to build its sheltering nest. Read the guide →
Mammals LC Rufous Elephant Shrew Elephantulus rufescens The rufous elephant shrew is one of the most thoroughly studied members of its order, its trail-patrolling and monogamous pair-bonding behaviour documented in detail across the savanna of East Africa. Read the guide →
Birds LC Rufous Hornero Furnarius rufus The rufous hornero builds a heavy domed nest of mud and straw shaped like a clay oven, with a curved inner wall hiding the chamber. It is Argentina's national bird and thrives around farms and towns. Read the guide →
Birds LC Rufous Motmot Baryphthengus martii The rufous motmot is one of the largest members of its family, identified by rich rufous underparts contrasting with a green back and long racket-tipped tail. Read the guide →
Birds LC Rufous Woodpecker Micropternus brachyurus The rufous woodpecker excavates its nest directly inside the active nests of tree ants, somehow avoiding the swarming defenders that would overwhelm almost any other bird attempting the same thing. Read the guide →
Birds LC Rufous-chested Dotterel Charadrius modestus The rufous-chested dotterel breeds across open Patagonian and Falkland Islands grassland, migrating north each winter to spend the non-breeding season across a much broader swath of South America. Read the guide →
Birds LC Rufous-legged Owl Strix rufipes The rufous-legged owl hunts through dense southern beech forest at night, identified by barred plumage and distinctively rust-coloured legs among its Patagonian owl relatives. Read the guide →
Birds LC Rufous-tailed Jacamar Galbula ruficauda The rufous-tailed jacamar catches butterflies and dragonflies in mid-air, then beats its prey against a branch to remove wings before swallowing it. Read the guide →
Birds LC Rufous-tailed Plantcutter Phytotoma rara The rufous-tailed plantcutter eats leaves and buds rather than insects or fruit, an unusual diet among songbirds enabled by a serrated bill built for cutting vegetation. Read the guide →
Birds LC Rufous-Vented Ground-Cuckoo Neomorphus geoffroyi The rufous-vented ground-cuckoo is a large, elusive rainforest predator that follows army ant swarms to ambush insects, spiders, and small lizards flushed out by the advancing ants. Read the guide →
Amphibians LC Running Frog Kassina A running frog is an African frog that walks and runs on alternating legs instead of hopping, a gait almost unique among frogs, and it can inflate its body to control buoyancy in water. Read the guide →
Reptiles LC Russell's Viper Daboia russelii Russell's viper is a chain-patterned snake of South Asian farmland and one of the biggest animal killers of people. Its venom wrecks blood clotting and the kidneys, and can cause disease years later. Read the guide →
Reptiles VU Russian Tortoise Testudo horsfieldii A small burrowing tortoise of the Central Asian steppe, the Russian tortoise is active just a few months a year and, in 1968, became the first Earth animal to travel around the Moon. Read the guide →
Invertebrates CR Rusty Patched Bumblebee Bombus affinis The rusty patched bumblebee became the first bee ever placed on the US endangered species list, its population having collapsed by an estimated 90 percent from disease, pesticides, and habitat loss. Read the guide →
Mammals NT Rusty-spotted Cat Prionailurus rubiginosus The rusty-spotted cat is one of the smallest cats in the world, a tiny, spotted hunter of India and Sri Lanka that is smaller than most domestic cats. Read the guide →
Fish LC Sabertooth Fish Evermannellidae The sabertooth fish carries a pair of oversized, blade-like fangs and, in some species, a single tubular eye built to gaze straight upward through the deep-sea darkness. Read the guide →
Birds LC Sabine's Gull Xema sabini Sabine's gull is unmistakable in flight, its wings marked with a bold triangular pattern of black, white, and grey unlike any other gull, and it carries a deeply forked tail more typical of a tern. Read the guide →
Mammals LC Sable Martes zibellina The sable's fur was historically the most valuable in the world, a Siberian forest hunter whose pelt trade helped drive centuries of Russian expansion eastward across the continent. Read the guide →
Mammals LC Sable Antelope Hippotragus niger The sable antelope's males turn almost jet black with age, and both sexes carry dramatic, deeply ridged horns long enough to drop to their knees and fight off attacking lions. Read the guide →
Fish LC Sablefish Anoplopoma fimbria The sablefish is a deep, cold-water fish marketed as black cod despite not being a cod at all, prized for an unusually high fat content that gives its flesh a rich, buttery texture when cooked. Read the guide →
Amphibians NT Sacramento Mountain Salamander Aneides hardii The Sacramento Mountain salamander survives on isolated sky-island peaks in New Mexico, each mountaintop population separated from the next by desert lowlands no salamander could ever cross. Read the guide →
Fish VU Sacramento Perch Archoplites interruptus The Sacramento perch is the only sunfish native west of the Rocky Mountains, once the top native predator of California's Central Valley before introduced fish pushed it to the edge of its own range. Read the guide →
Birds LC Sacred Kingfisher Todiramphus sanctus The sacred kingfisher takes its name from the reverence some Pacific island cultures once held for it, a bird that hunts as much on dry land as over water. Read the guide →
Invertebrates NE Sacred Scarab Scarabaeus sacer The sacred scarab was revered in ancient Egypt as a symbol of the sun's daily journey, rolling dung balls across the ground in a motion early observers compared to the sun crossing the sky. Read the guide →
Invertebrates LC Saddleback Caterpillar Acharia stimulea The saddleback caterpillar carries venomous spines capable of one of the most painful stings of any North American caterpillar, hidden beneath a green saddle marking that makes it easy to recognise. Read the guide →
Amphibians EN Sagalla Caecilian Boulengerula niedeni The Sagalla caecilian is a pink, limbless, burrowing amphibian found only on one Kenyan hill. It smells the soil with a pair of head tentacles, and its young eat their mother's skin. Read the guide →
Birds LC Sage Thrasher Oreoscoptes montanus The sage thrasher depends almost entirely on sagebrush habitat for nesting and shelter, and its bubbling, warbling song is delivered from atop the very shrubs the bird can't survive without. Read the guide →
Reptiles LC Sagebrush Lizard Sceloporus graciosus The sagebrush lizard occupies higher, cooler terrain than its larger, chunkier relative the western fence lizard, and the two can be genuinely hard to tell apart without a close look. Read the guide →
Mammals NT Saiga Antelope Saiga tatarica The saiga is an Ice Age relict of the Central Asian steppe with a bulbous, trunk-like nose. It crashed to ~50,000 by 2005, lost 200,000 to a 2015 bacterial outbreak, then rebounded past 1.9 million. Read the guide →
Reptiles VU Sailfin Dragon Hydrosaurus pustulatus The sailfin dragon is a metre-long Southeast Asian lizard with a tall skin-covered sail on its tail. It lives along rivers, swims and dives well, and its young can sprint across the water surface. Read the guide →
Fish LC Sailfin Molly Poecilia latipinna Male sailfin mollies raise a tall, sail-like dorsal fin to compete for female attention, a display so central that smaller, subordinate males rely on sneaking instead. Read the guide →
Fish LC Sailfish Istiophorus platypterus The sailfish is often called the sea's fastest fish, though the famous 100 km/h is a myth. It raises a huge sail and strobes blue bars to herd sardines, then slashes the bait ball with its bill. Read the guide →
Mammals LC Saki Monkey Pithecia pithecia The male saki monkey displays a striking black body with a pale, almost ghostly white face, a dramatic contrast to the browner, less conspicuous females of the species. Read the guide →
Amphibians VU Salado Salamander Eurycea chisholmensis The Salado salamander survives only around a small cluster of springs feeding one Texas creek, a population so localized that a single prolonged drought could threaten the entire species at once. Read the guide →
Amphibians NE Salamander Caudata A salamander is a tailed, lizard-shaped amphibian with soft moist skin, and as a group salamanders are the best limb-regenerators among vertebrates, regrowing legs and tails without a scar. Read the guide →
Fish LC Salema Sarpa salpa The salema is a silvery, gold-striped sea bream of Mediterranean and Atlantic shores that grazes in shoals on seaweed and seagrass, and whose flesh can occasionally cause hallucinations if eaten. Read the guide →
Invertebrates NE Sally Lightfoot Crab Grapsus grapsus The Sally lightfoot crab skitters sideways across wave-battered rocks with startling speed, changing from dull black as a juvenile into a brilliant red, orange, and blue adult. Read the guide →
Fish NE Salmon Oncorhynchus and Salmo A salmon is a fish born in a river, grown in the sea, and driven back to the exact stream it hatched in to spawn, a trip that for most Pacific salmon ends in death within days. Read the guide →
Invertebrates LC Salp Salpidae A salp is a barrel-shaped, jelly-clear ocean drifter that pumps water through its own body to move and feed at once, and can link end to end into chains stretching many feet long. Read the guide →
Birds EN Saltmarsh Sparrow Ammospiza caudacuta The saltmarsh sparrow nests so close to the tideline that eggs and chicks are regularly flooded out by high tides, a razor-thin margin now closing as sea levels rise faster than the bird can adapt. Read the guide →
Reptiles LC Saltwater Crocodile Crocodylus porosus The saltwater crocodile is the largest living reptile and has the strongest bite ever measured. Learn how it ambushes prey, crosses open ocean, and how it recovered from near-extinction. Read the guide →
Birds VU Salvin's Albatross Thalassarche salvini Salvin's albatross breeds almost entirely on two remote New Zealand island groups, concentrating most of its world population onto just a handful of sites across the Southern Ocean. Read the guide →
Mammals VU Sambar Deer Rusa unicolor The sambar deer is one of the largest deer species in Asia, a shaggy, water-loving giant that wallows in mud to cool off and serves as one of the tiger's most important prey species across its range. Read the guide →
Amphibians VU San Marcos Salamander Eurycea nana The San Marcos salamander lives only at the headwater springs of the San Marcos River, one of the smallest members of its genus and entirely dependent on a single spring system's flow. Read the guide →
Reptiles LC Sand Boa Eryx A sand boa is a small, blunt burrowing snake of dry country across Africa and Asia, an ambush hunter that lies buried with just its eyes showing, and the Kenyan sand boa is a popular, docile pet. Read the guide →
Mammals LC Sand Cat Felis margarita The sand cat is the only cat that lives in true desert, padding across dunes on fur-soled feet, needing no water, and digging sand vipers and gerbils out of the sand. Read the guide →
Invertebrates LC Sand Dollar Clypeasteroida A sand dollar is a flattened relative of the sea urchin that sifts food from sand using thousands of tiny, movable spines, leaving behind only its bleached, five-petalled shell after death. Read the guide →
Fish LC Sand Goby Pomatoschistus minutus The sand goby is a tiny, translucent, sand-coloured fish of European shallows that lives only a year or two, whose male guards eggs in a nest dug beneath a shell, and a staple prey of larger fish. Read the guide →
Fish LC Sand Lance Ammodytes The sand lance spends much of its life buried in clean sandy seafloor, only to emerge in vast schools that feed nearly every major predator in the water above, from seabirds to whales. Read the guide →
Reptiles LC Sand Lizard Lacerta agilis The sand lizard is a stocky, blotch-backed lizard of sandy heaths and dunes whose breeding males flush brilliant green, and in Britain it is a rare, protected species rebuilt by reintroduction. Read the guide →
Reptiles VU Sand Skink Plestiodon reynoldsi The sand skink is a Florida scrub lizard with legs so reduced they are nearly useless for walking, instead swimming through loose sand the way a fish swims through water. Read the guide →
Fish CR Sand Tiger Shark Carcharias taurus The sand tiger shark looks ferocious but is docile, gulps air to hang motionless in the water, and its embryos eat each other in the womb until one survivor is born from each side. Read the guide →
Birds LC Sanderling Calidris alba The sanderling chases each retreating wave down a sandy beach and races back ahead of the next one, probing for buried prey in a rhythm timed precisely to the surf. Read the guide →
Reptiles LC Sandfish Skink Scincus scincus The sandfish skink dives into loose desert sand and swims through it, rippling its smooth body in an S-shape like a fish in water. It can sense insects on the surface while completely buried. Read the guide →
Birds LC Sandgrouse Pterocles spp. The male sandgrouse carries water to his chicks in specialised belly feathers, soaking them at a distant waterhole and flying home for the young to drink from. Read the guide →
Birds LC Sandhill Crane Antigone canadensis Sandhill cranes stage by the hundreds of thousands on Nebraska's Platte River each spring. They dance year-round, mate for life, and bugle through a windpipe coiled like a trombone. Read the guide →
Birds LC Sandwich Tern Thalasseus sandvicensis The Sandwich tern takes its name not from the food but from the English town where it was first described, and carries a shaggy black crest that gives it a windswept look. Read the guide →
Amphibians NT Santa Cruz Black Salamander Aneides niger The Santa Cruz black salamander is confined to a small pocket of coastal California forest, and its solid black coloration offers almost no camouflage against the pale leaf litter it lives among. Read the guide →
Amphibians EN Santa Cruz Long-Toed Salamander Ambystoma macrodactylum croceum The Santa Cruz long-toed salamander survives in only a handful of ponds squeezed by California coastal development, one of the most narrowly range-restricted amphibians in North America. Read the guide →
Amphibians VU Santeetlah Dusky Salamander Desmognathus santeetlah The Santeetlah dusky salamander survives only in a small cluster of mountains on the North Carolina and Tennessee border, split from wider relatives by recent taxonomic revision. Read the guide →
Birds LC Sapsucker Sphyrapicus spp. The sapsucker drills neat rows of shallow wells into tree bark to drink the sap that wells up, a habit that also feeds hummingbirds and other birds that visit the same drilled trees afterward. Read the guide →
Fish NE Sarcastic Fringehead Neoclinus blanchardi The sarcastic fringehead is a small Pacific fish that lives in a borrowed shell or bottle and settles disputes by unfolding its mouth into a flaring, fanged display twice the size of its head. Read the guide →
Fish LC Sardine Sardina pilchardus A sardine is a small, silvery schooling fish whose annual migration off South Africa forms shoals large enough to be seen from space, one of the biggest gatherings of marine life on Earth. Read the guide →
Amphibians VU Sardinian Brook Salamander Speleomantes genei The Sardinian brook salamander is a lungless amphibian found only on Sardinia that catches prey by launching its entire tongue outward like a projectile, a trick shared by few salamanders. Read the guide →
Fish LC Sargassum Fish Histrio histrio The sargassum fish lives only in rafts of floating Sargassum weed, disguised as the weed with frond-like skin flaps. It clambers along on hand-shaped fins and gulps prey its own size. Read the guide →
Fish LC Sargo Diplodus sargus The sargo, or white seabream, is a silvery, barred sea bream of rocky Mediterranean and Atlantic coasts with a black saddle at the base of its tail and incisor-like teeth for scraping shellfish. Read the guide →
Birds VU Sarus Crane Antigone antigone The sarus crane is the tallest flying bird in the world, standing up to 1.8 metres, and in India it is a lasting symbol of marital devotion because pairs bond and hold a territory for life. Read the guide →
Birds LC Satin Bowerbird Ptilonorhynchus violaceus The male satin bowerbird builds a two-walled avenue of sticks on the forest floor, decorates it with dozens of blue objects, and paints the walls with chewed plant pulp to court females. Read the guide →
Birds NT Satyr Tragopan Tragopan satyra The satyr tragopan shares its dramatic inflatable throat wattle and raised head horns with its western relative, but wears a crimson body dotted with pale spots across a wider Himalayan range. Read the guide →
Fish LC Sauger Sander canadensis The sauger tolerates muddier, more turbid water than its close relative the walleye, and its heavily spotted dorsal fin is the clearest way to tell the two fish apart. Read the guide →
Reptiles LC Savannah Monitor Varanus exanthematicus The savannah monitor is a stocky African lizard that eats mostly beetles, millipedes, and snails, feasts in the rains and fasts underground in the dry season, and is badly served by the pet trade. Read the guide →
Birds LC Savannah Sparrow Passerculus sandwichensis The savannah sparrow varies so much in size and color across its enormous range that some coastal populations were once mistaken for entirely separate species before genetics settled the question. Read the guide →
Reptiles LC Saw-scaled Viper Echis carinatus The saw-scaled viper is a small snake blamed for more human deaths than almost any other, especially in rural Africa and Asia. Instead of hissing it rasps its rough scales together into a dry sizzle. Read the guide →
Fish CR Sawfish Pristidae A sawfish is a ray, not a shark, whose snout is drawn into a tooth-studded blade it swings sideways to stun fish and sense prey, and all five species are now Endangered or Critically Endangered. Read the guide →
Fish LC Sawshark Pristiophoridae The sawshark carries a pair of long, sensitive barbels partway along its toothed snout, using them to detect prey buried in sand before slashing sideways to stun it with the saw itself. Read the guide →
Birds LC Say's Phoebe Sayornis saya Say's phoebe often nests on building ledges and beneath bridges in open, arid country, and it pumps its tail up and down almost constantly while perched, a habit shared with its phoebe relatives. Read the guide →
Birds LC Scale-throated Earthcreeper Upucerthia dumetaria The scale-throated earthcreeper probes soil and leaf litter with a long, curved bill, a ground-dwelling ovenbird of Patagonian scrub that rarely strays far from the surface. Read the guide →
Birds LC Scaled Quail Callipepla squamata The scaled quail wears feathers edged in dark scallops across its body, a mail-like pattern that gives the species its name, topped with a short, bushy white-tipped crest. Read the guide →
Invertebrates LC Scallop Pectinidae A scallop is one of the few bivalves that can actually swim, clapping its ribbed, fan-shaped shell together to jet away from a slow-approaching predator like a sea star. Read the guide →
Fish CR Scalloped Hammerhead Shark Sphyrna lewini The scalloped hammerhead gathers in daytime schools of over a hundred sharks near seamounts, unusual for a species otherwise thought solitary. Its notched head boosts vision and prey-sensing. Read the guide →
Invertebrates EN Scaly-foot Snail Chrysomallon squamiferum The scaly-foot snail armours its foot with plates built partly from iron sulfide, the only animal known to incorporate this mineral into its skeleton, and survives entirely on internal bacteria. Read the guide →
Birds LC Scarlet Ibis Eudocimus ruber The scarlet ibis is one of the most vividly coloured birds alive, a brilliant red wader of South American mangroves. The colour comes entirely from the crabs and shrimp it eats. Read the guide →
Reptiles LC Scarlet Kingsnake Lampropeltis elapsoides The scarlet kingsnake is a small, harmless snake ringed in red, black, and yellow — a near-perfect copy of the venomous coral snake it lives alongside, and a textbook case of protective mimicry. Read the guide →
Birds LC Scarlet Macaw Ara macao The scarlet macaw is a metre-long red, yellow, and blue parrot of Central and South American rainforests. Pairs mate for life, fly to clay licks to eat mineral-rich earth, and can live 50 years. Read the guide →
Reptiles LC Scarlet Snake Cemophora coccinea The scarlet snake is a harmless, secretive burrower whose red, black, and yellow bands closely mimic the pattern of venomous coral snakes, and it specialises almost entirely on reptile eggs. Read the guide →
Birds LC Scarlet Tanager Piranga olivacea The scarlet tanager transforms between seasons, swapping brilliant red breeding plumage for a dull olive-green that lets a male vanish into the same forest canopy where he was once impossible to miss. Read the guide →
Birds LC Scarlet-Rumped Tanager Ramphocelus passerinii The scarlet-rumped tanager is otherwise solid black except for a single vivid patch of red across the rump, a striking flash of colour in flight. Read the guide →
Birds LC Scissor-Tailed Flycatcher Tyrannus forficatus The scissor-tailed flycatcher trails a deeply forked tail longer than its own body, and it will dive-bomb hawks and crows many times its size that stray too near the nest. Read the guide →
Fish LC Scissortail Rasbora Rasbora trilineata The scissortail rasbora flicks its bold, black-and-white banded tail fin open and shut like a pair of scissors, a distinctive habit that gives the species both its name and its constant motion. Read the guide →
Invertebrates NE Scorpion Scorpiones A scorpion is an ancient arachnid with grasping pincers and a stinging tail, glows blue-green under ultraviolet light, and can slow its body down enough to survive a year without food. Read the guide →
Fish LC Scorpionfish Scorpaenidae A scorpionfish disappears into the reef by looking like a rock or a clump of algae, then relies on venomous spines rather than speed the moment a predator or an unwary hand gets too close. Read the guide →
Invertebrates NE Scorpionfly Panorpidae The male scorpionfly carries a bulbous, upward-curving tail that closely resembles a scorpion's stinger, though the harmless structure exists only for mating, not for defence. Read the guide →
Amphibians VU Scott Bar Salamander Plethodon asupak The Scott Bar salamander was only formally described in 2005, a lungless amphibian known from a single small mountain range in northern California and nowhere else on Earth. Read the guide →
Birds LC Screamer Anhimidae A screamer carries sharp bony spurs on each wing for fighting rivals, unusually dense bones instead of the typical lightweight bird skeleton, and a call loud enough to carry for miles. Read the guide →
Birds LC Screech Owl Megascops A screech owl presses tight against a tree trunk with feathers held flat and ear tufts raised, its mottled grey-brown plumage disappearing so completely into bark that most people walk right past one. Read the guide →
Fish LC Sculpin Cottidae A sculpin is a big-headed, spiny, bottom-dwelling fish that relies on camouflage and stillness rather than speed, found in cold coastal waters, tide pools, and freshwater streams worldwide. Read the guide →
Invertebrates NE Sea Anemone Actiniaria A sea anemone is a soft relative of coral and jellyfish that grips a rock, catches fish and plankton with venom-tipped tentacles, can crawl or swim to escape danger, and may live over a century. Read the guide →
Invertebrates NE Sea Angel Clione limacina The sea angel is a tiny transparent sea slug that has lost its shell and swims by flapping two wings. It feeds almost only on shelled sea butterflies, seized with tentacles that shoot from its head. Read the guide →
Invertebrates NE Sea Apple Pseudocolochirus violaceus The sea apple is a vividly coloured sea cucumber that filters plankton with feathery tentacles, and when threatened it can release sticky, toxic threads potent enough to kill nearby tankmates. Read the guide →
Invertebrates NE Sea Bunny Jorunna parva The sea bunny is a small nudibranch covered in soft-looking projections that resemble rabbit fur and ears, one of the most photographed sea slugs for its uncanny cuteness. Read the guide →
Invertebrates NE Sea Butterfly Thecosomata A sea butterfly is a tiny swimming sea snail that flaps a pair of wing-like fins instead of crawling, and its thin, aragonite shell is now dissolving faster in an ocean growing more acidic every year. Read the guide →
Invertebrates DD Sea Cucumber Holothuroidea The sea cucumber crawls the seafloor eating sediment and digesting the organic scraps within it, recycling nutrients across the ocean floor. Some species eject their own organs at predators. Read the guide →
Invertebrates LC Sea Firefly Vargula A sea firefly is a tiny crustacean that glows brilliant blue when disturbed, and dried, crushed specimens were reportedly used by soldiers in the Pacific as a covert, silent source of light. Read the guide →
Invertebrates LC Sea Hare Aplysia A sea hare is a large sea slug that releases a cloud of purple ink when attacked, and its unusually large nerve cells have made it one of the most important animals in the history of neuroscience. Read the guide →
Reptiles LC Sea Krait Laticauda A sea krait is a mild-mannered, banded, venomous sea snake that, unlike almost all other sea snakes, still comes ashore to digest food, mate, and lay its eggs on land. Read the guide →
Fish LC Sea Lamprey Petromyzon marinus The sea lamprey is a jawless fish older than the dinosaurs. In place of jaws it has a round sucker disc lined with rings of horny teeth and a rasping tongue it uses to bore into a living fish. Read the guide →
Invertebrates LC Sea Mouse Aphrodita aculeata The sea mouse is a marine worm, not a mammal, covered in bristles that flash brilliant iridescent blue and green, a structural colour effect striking enough that physicists have studied it directly. Read the guide →
Invertebrates LC Sea Nettle Chrysaora quinquecirrha The sea nettle trails long, thin, stinging tentacles beneath a golden-brown bell striped in reddish-brown, becoming abundant enough some summers to shape swimming plans across entire coastal bays. Read the guide →
Mammals EN Sea Otter Enhydra lutris The sea otter has no blubber and survives the cold Pacific on the densest fur of any animal, using rocks to crack shellfish. Learn how it keeps kelp forests alive — and why it is Endangered. Read the guide →
Invertebrates LC Sea Pen Pennatulacea A sea pen is a colonial animal shaped like an antique quill pen, built from hundreds of tiny polyps sharing one skeleton, and many species glow with their own bioluminescent light when touched. Read the guide →
Invertebrates NE Sea Pig Scotoplanes globosa The sea pig is a plump pink sea cucumber that walks the deep ocean floor on rows of tube-foot legs, often in herds facing the current, feeding on the richest sludge and the remains of whale falls. Read the guide →
Reptiles NE Sea Snake Hydrophiinae A sea snake is a venomous relative of the cobras that lives its whole life in warm coastal seas, breathes partly through its skin, and swims with a flattened, paddle-shaped tail. Read the guide →
Invertebrates NE Sea Spider Pycnogonida A sea spider is mostly legs. Its body is so small that its gut and ovaries run out into the legs, it has no gills, and the male carries the eggs. Antarctic species span over 50 cm. Read the guide →
Invertebrates LC Sea Squirt Ascidiacea A sea squirt starts life as a free-swimming, tadpole-like larva with a primitive spinal cord, then settles down, attaches to a rock, and digests its own brain and nerve cord. Read the guide →
Fish LC Sea Toad Chaunax The sea toad walks along the seafloor on stubby, leg-like fins rather than swimming, a squat, loose-skinned relative of the anglerfish with its own small built-in fishing lure. Read the guide →
Reptiles EN Sea Turtle Chelonioidea A sea turtle is an ocean-going reptile with flipper limbs it cannot pull into its shell, crossing entire oceans and returning to nest on the beach where it hatched decades before. Read the guide →
Invertebrates NE Sea Urchin Echinoidea A sea urchin is a spiny, ball-shaped relative of the starfish that grazes seaweed with a five-toothed jaw on its underside, and where its predators are gone it can strip a kelp forest to bare rock. Read the guide →
Fish VU Seahorse Hippocampus kuda The seahorse is a fish that swims upright, grips seagrass with a monkey-like tail, and in which the male carries the pregnancy. Learn how this slow, armoured ambush hunter lives. Read the guide →
Mammals NE Seal Pinnipedia A seal is a marine mammal that swims with flippers and hunts on long, deep breath-hold dives, hauling out on land or ice to rest, moult, and breed; the group includes the sea lions and the walrus. Read the guide →
Amphibians LC Seal Salamander Desmognathus monticola A stout Appalachian brook salamander, the seal salamander guards a burrow at the water's edge, lunging out to snatch passing insects, and breathes entirely through its moist skin. Read the guide →
Birds NT Seaside Cinclodes Cinclodes nigrofumosus The seaside cinclodes forages directly in the intertidal zone of the Chilean coast, an unusual lifestyle for a member of the ovenbird family. Read the guide →
Birds NT Seaside Sparrow Ammospiza maritima The seaside sparrow spends its life within a narrow band of tidal salt marsh, including one Florida population, the Cape Sable seaside sparrow, so range-restricted it is now Endangered. Read the guide →
Mammals LC Seba's Short-Tailed Bat Carollia perspicillata Seba's short-tailed bat is among the most abundant bats in the Neotropics, a key disperser of pioneer plant seeds that helps regrow cleared rainforest. Read the guide →
Birds EN Secretary Bird Sagittarius serpentarius The secretary bird is a long-legged African raptor that hunts on foot, killing snakes and other prey by stamping with a force five times its body weight, delivered in a fraction of a second. Read the guide →
Amphibians LC Seepage Salamander Desmognathus aeneus The seepage salamander is one of the smallest salamanders in North America, and unlike most of its dusky salamander relatives, it skips the aquatic larval stage entirely. Read the guide →
Mammals EN Sei Whale Balaenoptera borealis The sei whale is the third-largest baleen whale and one of the fastest, capable of short bursts near 50 kilometres per hour, a speed that made it one of the last great whales targeted by whalers. Read the guide →
Mammals LC Selous's Mongoose Paracynictis selousi Selous's mongoose digs its own extensive burrow systems rather than relying on abandoned ones, a moderately social southern African species named after a nineteenth-century hunter-naturalist. Read the guide →
Mammals LC Senegal Bushbaby Galago senegalensis The Senegal bushbaby is a small African primate with huge ears and eyes that leaps between branches at night, washes its hands and feet with urine for grip, and wails like a crying baby. Read the guide →
Amphibians NT Sequoia Slender Salamander Batrachoseps kawia The Sequoia slender salamander lives only in a narrow stretch of the southern Sierra Nevada foothills, breathing entirely through skin thin enough to fit into the tightest of underground crevices. Read the guide →
Amphibians LC Sequoyah Slimy Salamander Plethodon sequoyah The Sequoyah slimy salamander is named for the Cherokee scholar who devised a writing system for the Cherokee language, occupying a range in the Ozark and Ouachita highlands far from most relatives. Read the guide →
Fish LC Sergeant Major Damselfish Abudefduf saxatilis The sergeant major damselfish carries five bold black bars across a yellow-and-silver body, a striped pattern that resembles military rank insignia and gives the species its common name. Read the guide →
Birds LC Seriema Cariamidae A seriema is a long-legged South American ground bird that kills snakes and lizards by repeatedly smashing them against the ground or a rock, more terror bird than songbird. Read the guide →
Mammals LC Serotine Eptesicus serotinus The serotine is a large, dark European bat with a slow, heavy flight that hunts dung beetles and cockchafers over pastures and around street lights, and roosts in roofs. Read the guide →
Mammals VU Serow Capricornis sumatraensis The serow marks its steep forest territory with a strong-smelling secretion from glands near its eyes, a solitary Asian goat-antelope built for near-vertical, densely wooded slopes. Read the guide →
Mammals LC Serval Leptailurus serval The serval is a slender African wild cat with the longest legs and largest ears relative to body size of any feline. Read the guide →
Invertebrates LC Seven-arm Octopus Haliphron atlanticus The seven-arm octopus keeps its eighth arm coiled up in a pouch beneath one eye, making it look like it only has seven, while ranking among the largest and heaviest octopus species known. Read the guide →
Fish LC Severum Heros severus The severum carries a deep, disc-shaped body reminiscent of a large discus, with young fish showing bold vertical banding that fades into a calmer, more mottled pattern with age. Read the guide →
Mammals CR Seychelles Sheath-tailed Bat Coleura seychellensis The Seychelles sheath-tailed bat is a tiny, Critically Endangered insect-eating bat found only in the Seychelles, where just a handful of small colonies survive. Read the guide →
Fish NT Shad Alosa sapidissima Shad once ran up eastern American rivers in numbers so enormous that Revolutionary War soldiers reportedly survived on the spring run, a keystone fish whose migration still shapes river policy. Read the guide →
Fish LC Shadow Bass Ambloplites ariommus The shadow bass gets its name from lurking motionless in shaded cover along undercut banks and logs, ambushing prey that wanders too close rather than chasing anything down in open water. Read the guide →
Fish LC Shanny Lipophrys pholis The shanny, or common blenny, is a small, scaleless, rock-pool fish of north-eastern Atlantic shores that survives out of water at low tide and can find its way home to its pool after being moved. Read the guide →
Fish NE Shark Selachimorpha A shark is a fish with a skeleton of cartilage instead of bone, a lineage older than trees, that senses hidden prey through electric fields and replaces its teeth on a conveyor belt for life. Read the guide →
Reptiles NT Sharp-Tailed Snake Contia tenuis The sharp-tailed snake uses a sharp spine at the tip of its tail to pin down slippery slugs while it works its curved teeth into position, a specialised trick almost no other snake needs. Read the guide →
Amphibians VU Shasta Salamander Hydromantes shastae The Shasta salamander lives only in limestone habitat near Shasta Lake, and a proposed enlargement of Shasta Dam threatens to permanently flood a significant share of the small range it depends on. Read the guide →
Mammals LC Shaw's Jird Meriones shawi Shaw's jird is a gerbil-like burrowing rodent of North Africa's semi-arid steppes and farmland that stores seeds underground and has been found to carry the parasite behind cutaneous leishmaniasis. Read the guide →
Birds LC Shearwater Ardenna spp. The shearwater glides low over wave troughs on stiff wings, navigates ocean basins using an unusually strong sense of smell, and some species migrate tens of thousands of kilometres every year. Read the guide →
Birds LC Sheathbill Chionis A sheathbill is the only Antarctic bird without webbed feet, a stocky white scavenger that steals penguin eggs and chicks and eats almost anything else it can find along the shore. Read the guide →
Amphibians LC Sheep Frog Hypopachus variolosus The sheep frog is a small burrowing amphibian named for a call that sounds remarkably like a bleating sheep, and it defends itself with a distasteful skin secretion rather than trying to flee. Read the guide →
Fish LC Sheepshead Archosargus probatocephalus The sheepshead is a striped coastal fish of the western Atlantic with a set of broad, oddly human-looking teeth it uses to crush barnacles, oysters, crabs and other hard-shelled prey. Read the guide →
Fish LC Sheepshead Minnow Cyprinodon variegatus The sheepshead minnow tolerates salinity from fresh water to twice that of seawater, making it a favorite research subject despite sharing its name with an unrelated larger fish. Read the guide →
Reptiles LC Sheltopusik Pseudopus apodus The sheltopusik is the largest legless lizard, a metre-long armour-scaled reptile of southeast Europe and Asia that looks like a snake but has eyelids and a tail that shatters when grabbed. Read the guide →
Amphibians VU Shenandoah Mountain Salamander Plethodon virginia The Shenandoah Mountain salamander survives on a handful of isolated Virginia peaks, squeezed onto dry ridgetops after a more common relative pushed it out of the valleys below. Read the guide →
Amphibians EN Shenandoah Salamander Plethodon shenandoah The Shenandoah salamander survives only on a handful of rocky talus slopes atop three mountains in Virginia, squeezed into that narrow habitat by direct competition with a more common relative. Read the guide →
Mammals LC Shepherd's Beaked Whale Tasmacetus shepherdi Shepherd's beaked whale is the only beaked whale with a full set of functional teeth in both jaws, unusual for a family typically reduced to just one or two visible teeth in adult males. Read the guide →
Reptiles LC Shingleback Skink Tiliqua rugosa The shingleback is a slow, armoured Australian skink whose fat tail mimics its head to confuse predators. Pairs reunite with the same partner year after year, some for over 20 years. Read the guide →
Fish VU Shoal Bass Micropterus cataractae The shoal bass depends on rocky river shoals so specifically that dam construction across its native rivers has fragmented the species into isolated populations that can no longer reach one another. Read the guide →
Birds VU Shoebill Balaeniceps rex The shoebill is a towering grey swamp bird with a huge clog-shaped bill that it uses to catch lungfish and baby crocodiles. It stands motionless for hours, then strikes in a full-body lunge. Read the guide →
Mammals LC Short-Eared Elephant Shrew Macroscelides proboscideus The short-eared elephant shrew is one of the smallest members of its order, surviving in the arid Karoo of southern Africa without digging a single burrow of its own. Read the guide →
Birds LC Short-Eared Owl Asio flammeus The short-eared owl hunts readily in broad daylight, flying low over open fields with a floppy, moth-like wingbeat setting it apart from most other, strictly nocturnal North American owls. Read the guide →
Reptiles LC Short-Horned Lizard Phrynosoma hernandesi The short-horned lizard ranges further north and higher into the mountains than any other horned lizard, surviving the cold by giving live birth instead of laying eggs. Read the guide →
Birds VU Short-tailed Albatross Phoebastria albatrus The short-tailed albatross was hunted so intensively for its feathers that it was once believed extinct, before survivors were rediscovered breeding on a volcanic island decades later. Read the guide →
Mammals CR Short-tailed Chinchilla Chinchilla chinchilla The short-tailed chinchilla once ranged across the high Andes but was hunted to the brink of extinction for its fur, surviving now in only a few remote Chilean sites. Read the guide →
Mammals LC Short-Tailed Mongoose Herpestes brachyurus The short-tailed mongoose carries a noticeably stubbier tail than most of its relatives, a solitary rainforest species of Borneo, Sumatra, and the Malay Peninsula rarely seen in the open. Read the guide →
Reptiles VU Short-Tailed Snake Stilosoma extenuatum The short-tailed snake is a rare Florida endemic that hunts almost nothing but other small reptiles, ambushing them underground with a long, constricting body built for burrowing after prey. Read the guide →
Fish DD Shortbill Spearfish Tetrapturus angustirostris The shortbill spearfish is the smallest billfish species and one of the least studied, carrying a notably shorter bill than its marlin and swordfish relatives. Read the guide →
Fish EN Shortfin Mako Shark Isurus oxyrinchus The shortfin mako is the fastest shark in the sea — bursts to around 70 km/h — and one of the few warm-blooded fish. It is now Endangered from overfishing. Read the guide →
Fish LC Shorthead Redhorse Moxostoma macrolepidotum The shorthead redhorse vacuums up mouthfuls of river-bottom sediment and sorts out edible invertebrates before spitting the rest back out, a feeding style shared across its entire sucker family. Read the guide →
Fish LC Shortnose Gar Lepisosteus platostomus The shortnose gar can gulp air at the surface using a swim bladder that works like a primitive lung, letting it survive in water too low in oxygen for most other fish. Read the guide →
Fish EN Shortnose Sturgeon Acipenser brevirostrum The shortnose sturgeon is one of the smallest sturgeons in North America, an armoured fish essentially unchanged for tens of millions of years, now endangered by dams blocking its spawning rivers. Read the guide →
Birds LC Shovel-billed Kookaburra Clytoceyx rex The shovel-billed kookaburra carries a massive, broad bill built for digging earthworms out of the forest floor, a hunting method unlike anything else in the entire kingfisher family. Read the guide →
Amphibians LC Shovel-nosed Salamander Desmognathus marmoratus The shovel-nosed salamander never leaves the water, living its whole life wedged under stones in cold Appalachian torrents and digging through the gravel with a flattened, spade-like snout. Read the guide →
Fish LC Shovelnose Sturgeon Scaphirhynchus platorynchus The shovelnose sturgeon is the smallest sturgeon species in North America, using a flattened, shovel-shaped snout to stir up river-bottom sediment and expose the small invertebrates hidden underneath. Read the guide →
Birds LC Shrike Lanius A shrike is a songbird with a hooked, predator-like beak that impales lizards, insects, and small rodents on thorns and barbed wire, earning it the nickname the butcher bird. Read the guide →
Invertebrates NE Shrimp Caridea and Dendrobranchiata A shrimp is a small, slender swimming crustacean with a fan tail for flicking backward out of danger, and shrimp of some kind live in nearly every wet habitat, from the abyss to hot springs. Read the guide →
Birds NT Shy Albatross Thalassarche cauta The shy albatross is the largest of the mollymawks and the only albatross species that breeds exclusively within Australian territory, nesting on just three Tasmanian islands. Read the guide →
Mammals EN Siamang Symphalangus syndactylus The siamang inflates a throat sac into a resonating chamber, turning its calls into some of the loudest sounds any land animal can produce, audible for kilometres. Read the guide →
Reptiles CR Siamese Crocodile Crocodylus siamensis The Siamese crocodile is a medium-sized freshwater crocodile of Southeast Asia, once widespread and now Critically Endangered, with tiny wild populations kept alive by protection and breeding. Read the guide →
Fish VU Siamese Fighting Fish Betta splendens The Siamese fighting fish breathes air from the surface, builds nests of bubbles, and flares into a blaze of fins at any rival. Wild bettas are a threatened brown fish from Thai floodplains. Read the guide →
Mammals LC Siberian Chipmunk Eutamias sibiricus The Siberian chipmunk is the only chipmunk native to Eurasia, a five-striped forest rodent that hoards seeds for winter and has become invasive where pets escaped in Europe. Read the guide →
Mammals NT Siberian Flying Squirrel Pteromys volans The Siberian flying squirrel glides silently between old-growth trees using a furred membrane, a species increasingly restricted to Europe's dwindling ancient forests. Read the guide →
Mammals LC Siberian Polecat Mustela eversmanii The Siberian polecat has served as a research stand-in for its critically endangered American relative, the black-footed ferret, helping scientists refine reintroduction techniques. Read the guide →
Reptiles LC Side-blotched Lizard Uta stansburiana The side-blotched lizard is a small, common lizard of the western deserts whose males come in three throat colours that beat each other in an endless rock-paper-scissors cycle. Read the guide →
Reptiles LC Sidewinder Crotalus cerastes The sidewinder crosses loose sand by throwing its body sideways in flowing loops, touching down at only two points at once and leaving a trail of separate J-shaped marks. Raised scales shade its eyes. Read the guide →
Amphibians EN Sierra Nevada Yellow-Legged Frog Rana sierrae The Sierra Nevada yellow-legged frog has vanished from the vast majority of its historical high-elevation lakes, largely because trout introduced for sport fishing prey heavily on its tadpoles. Read the guide →
Amphibians LC Sierra Newt Taricha sierrae A Sierra newt is a stout newt of the western Sierra Nevada foothills, recently split from the California newt, whose skin holds tetrodotoxin and whose spring migrations cross roads by the thousand. Read the guide →
Amphibians LC Sierran Treefrog Pseudacris sierra The Sierran treefrog was only recognised as its own species after genetic study split a once wide-ranging Pacific treefrog, dividing California's population from relatives to the north and south. Read the guide →
Invertebrates LC Signal Crayfish Pacifastacus leniusculus The signal crayfish is a large, bold North American crayfish with a pale patch on each claw that was introduced to Europe for farming and is now an invader that carries plague to native crayfish. Read the guide →
Mammals LC Sika Deer Cervus nippon The sika deer keeps its white spots into adulthood in many populations, a small East Asian deer whose eerie whistling call sounds nothing like the roar of the red deer. Read the guide →
Mammals LC Silky Anteater Cyclopes didactylus The silky anteater is the smallest anteater species, spending nearly its entire life clinging motionless to branches by day and resembling a ball of silvery fur rather than a typical anteater. Read the guide →
Fish LC Silver Arowana Osteoglossum bicirrhosum The silver arowana hunts at the surface of Amazon backwaters and leaps over a metre out of the water to snatch insects, birds and bats from branches. The male broods dozens of eggs inside his mouth. Read the guide →
Fish LC Silver Bream Blicca bjoerkna The silver bream, or white bream, is a small, deep-bodied, silvery shoaling fish of slow European rivers and lakes that resembles a young common bream but has larger eyes and pinkish fins. Read the guide →
Fish NT Silver Carp Hypophthalmichthys molitrix The silver carp is an Asian filter-feeding fish that has overrun the Mississippi basin and is infamous for hurling its heavy body clear of the water when startled by a boat motor. Read the guide →
Fish LC Silver Dollar Fish Metynnis argenteus The silver dollar fish is a flat, round-bodied Amazon basin species named for its resemblance to a shining coin, a peaceful schooling relative of the piranha. Read the guide →
Birds LC Silver Pheasant Lophura nycthemera The silver pheasant flashes a stark black underside against a silvery-white back, a striking two-tone contrast set off by bright red bare skin covering much of the face. Read the guide →
Fish LC Silver Redhorse Moxostoma anisurum The silver redhorse is among the largest members of the redhorse group, with a silvery body and grey rather than red fins, a plainer look than several of its more brightly finned relatives. Read the guide →
Birds LC Silver-Beaked Tanager Ramphocelus carbo The silver-beaked tanager pairs deep velvety red-black plumage with a strikingly pale lower bill that catches the eye even in dim forest light. Read the guide →
Mammals LC Silver-Haired Bat Lasionycteris noctivagans The silver-haired bat flies with a slow, fluttering pattern low over water and clearings, a dark, silver-tipped species that roosts alone behind loose bark rather than gathering in large colonies. Read the guide →
Invertebrates LC Silver-Spotted Skipper Epargyreus clarus The silver-spotted skipper carries a bold metallic-silver patch under each hindwing, a mirror-bright marking visible in flight that makes it one of the most recognisable skippers in North America. Read the guide →
Invertebrates LC Silver-washed Fritillary Argynnis paphia The silver-washed fritillary is a large orange woodland butterfly with black spots and silvery streaks beneath, whose females lay eggs in tree bark and sometimes appear in a rare olive-green form. Read the guide →
Invertebrates NE Silverfish Lepisma saccharinum A silverfish is a small, wingless, teardrop-shaped insect from one of the most ancient insect lineages, that lives in damp corners of houses eating starch, paper, and glue, and can live for years. Read the guide →
Fish LC Silverjaw Minnow Notropis buccatus The silverjaw minnow has a distinctly fleshy, overhanging snout used to root through sand and gravel, and a translucent silvery patch on the lower jaw that gives the species its common name. Read the guide →
Mammals EN Silvery Gibbon Hylobates moloch The silvery gibbon survives only in fragmented forest patches on the densely populated island of Java, one of the most endangered gibbon species on Earth. Read the guide →
Birds LC Silvery Grebe Podiceps occipitalis The silvery grebe forms dense, sociable breeding colonies on lakes across southern South America, diving underwater to hunt small fish and invertebrates using feet set far back on its body. Read the guide →
Invertebrates LC Siphonophore Siphonophorae A siphonophore is not one animal but a colony of thousands of genetically identical, specialised individuals fused together, some stretching longer than a blue whale. Read the guide →
Amphibians NE Siren Sirenidae A siren is an eel-shaped aquatic salamander that keeps its feathery gills for life, has only tiny front legs and no hind legs at all, and can seal itself in a mud cocoon to survive a pond drying up. Read the guide →
Amphibians VU Siskiyou Mountains Salamander Plethodon stormi The Siskiyou Mountains salamander depends on rocky forest talus so specific that logging near its habitat can eliminate a local population without a single tree above ground being disturbed directly. Read the guide →
Mammals LC Sitatunga Tragelaphus spekii The sitatunga has splayed, elongated hooves built for walking on floating swamp vegetation, and can submerge almost entirely underwater to hide from predators. Read the guide →
Reptiles LC Six-Lined Racerunner Aspidoscelis sexlineata The six-lined racerunner is built almost entirely for speed, a striped, whip-fast lizard that can outrun most predators across open ground and rarely stops moving long enough to be caught looking. Read the guide →
Invertebrates NE Six-spot Burnet Zygaena filipendulae The six-spot burnet is a day-flying moth with metallic green-black forewings and six crimson spots, which advertises its cyanide-based toxicity and spins a papery yellow cocoon on a grass stem. Read the guide →
Invertebrates LC Six-Spotted Tiger Beetle Cicindela sexguttata The six-spotted tiger beetle hunts down prey at a sprinting speed so fast relative to its body size that it must periodically stop running just to let its eyes catch up and refocus. Read the guide →
Invertebrates LC Skeleton Shrimp Caprellidae A skeleton shrimp is a stick-thin crustacean that clings to seaweed with its rear legs while striking at passing prey with mantis-like grasping front limbs, a body built almost entirely for ambush. Read the guide →
Reptiles NE Skink Scincidae A skink is a smooth, close-scaled lizard with a wedge head and a long tapering tail, built for slipping through grass and leaf litter, and many kinds have lost their legs and burrow like snakes. Read the guide →
Reptiles LC Slender Glass Lizard Ophisaurus attenuatus The slender glass lizard is even more slender and lightly built than its relatives, with a tail that can stretch to nearly two-thirds of its total body length before it ever needs to break one off. Read the guide →
Mammals EN Slender Loris Loris tardigradus The slender loris moves with slow, deliberate precision on extremely thin limbs, using enormous round eyes to hunt insects in complete darkness. Read the guide →
Mammals LC Slender Mongoose Galerella sanguinea The slender mongoose lives alone across nearly every habitat type in sub-Saharan Africa, identified by a distinctive black-tipped tail that stands out as it moves through cover. Read the guide →
Amphibians LC Slender Salamander Batrachoseps Slender salamanders are lungless western North American amphibians so long and thin they are often mistaken for earthworms; caught, they coil like a watch spring and then unspring to bounce away. Read the guide →
Birds NT Slender-billed Parakeet Enicognathus leptorhynchus The slender-billed parakeet digs up roots and bulbs underground using an unusually long, curved upper bill found in no other parrot species, sometimes bringing it into conflict with farmers. Read the guide →
Birds LC Slender-billed Prion Pachyptila belcheri The slender-billed prion has the narrowest bill of any prion species and a notably pale face, breeding in enormous burrow colonies across the Falkland Islands and other subantarctic sites. Read the guide →
Mammals EN Slender-Horned Gazelle Gazella leptoceros The slender-horned gazelle has broad, splayed hooves built for walking on loose sand, one of the palest and most specialized gazelle species surviving deep within the Sahara's dune fields. Read the guide →
Reptiles CR Slender-snouted Crocodile Mecistops cataphractus The slender-snouted crocodile is a shy, narrow-snouted fish-eater of West and Central African rivers and forest swamps, now Critically Endangered through hunting for bushmeat and loss of habitat. Read the guide →
Fish LC Slickhead Alepocephalidae The slickhead gets its name from a smooth, scaleless head, and many species feed almost entirely on low-energy jellyfish and other gelatinous prey most fish avoid. Read the guide →
Amphibians LC Slimy Salamander Plethodon glutinosus The slimy salamander is a lungless woodland salamander of the eastern US whose skin, when the animal is grabbed, releases a glue so strong it can cement a predator's jaws shut for days. Read the guide →
Fish LC Slimy Sculpin Cottus cognatus The slimy sculpin has no swim bladder at all and coats itself in an unusually thick layer of mucus, an adaptation that lets it survive being frozen into surface ice during the coldest winters. Read the guide →
Invertebrates NE Slipper Limpet Crepidula fornicata The slipper limpet is a stacking sea snail from North America that arrived in Europe with imported oysters, lives in chains in which the bottom animals are female, and now smothers shellfish beds. Read the guide →
Mammals LC Sloth Bradypus variegatus The sloth is the slowest mammal on Earth, moving and digesting so slowly that algae grows in its fur. Learn why it only comes down from the canopy once a week — and why that trip is so dangerous. Read the guide →
Mammals VU Sloth Bear Melursus ursinus The sloth bear is a shaggy, termite-slurping bear of the Indian subcontinent that carries its cubs on its back — and is responsible for more human maulings than any other bear. Learn how and why. Read the guide →
Mammals EN Slow Loris Nycticebus The slow loris is the only venomous primate. It licks a gland on its inner elbow, mixes the fluid with saliva, and bites a swollen, sometimes anaphylactic wound. It creeps the night canopy in silence. Read the guide →
Reptiles LC Slow Worm Anguis fragilis The slow worm is not a worm or a snake but a legless lizard, a smooth bronze burrower of European gardens that blinks, sheds its tail, and can live past 30 years, sometimes past 50. Read the guide →
Invertebrates NE Slug Gastropoda A slug is a land snail that has lost its shell, gliding on a ribbon of mucus with its eyes on stalks, and while gardeners fear it, most species eat rotting matter, not living plants. Read the guide →
Mammals LC Small Asian Mongoose Urva javanica The small Asian mongoose was long classified as the same species as the small Indian mongoose before a taxonomic revision split them apart, keeping this one native to Southeast Asia. Read the guide →
Invertebrates LC Small Heath Coenonympha pamphilus The small heath is a tiny orange-buff butterfly of open grassland that almost always rests with its wings closed, one of the most widespread of its group but declining in parts of Britain. Read the guide →
Mammals LC Small Indian Civet Viverricula indica The small Indian civet was historically farmed for the musky secretion of its scent glands, once a prized ingredient in traditional perfume before synthetic alternatives took over. Read the guide →
Invertebrates LC Small Tortoiseshell Aglais urticae The small tortoiseshell is a familiar orange-and-black European butterfly whose caterpillars feed together in silk webs on nettles and whose numbers have fallen sharply in parts of Britain. Read the guide →
Fish NT Small-eyed Ray Raja microocellata The small-eyed ray is a medium-sized, brown, pale-spotted ray of shallow sandy seabeds in the north-eastern Atlantic that is named for its small eyes and has declined under fishing pressure. Read the guide →
Amphibians LC Small-Mouthed Salamander Ambystoma texanum The small-mouthed salamander gets its name from a narrow mouth built for pulling earthworms out of soil, and its genes have fuelled one of the strangest reproductive lineages among salamanders. Read the guide →
Fish LC Small-spotted Catshark Scyliorhinus canicula The small-spotted catshark, or lesser spotted dogfish, is the commonest small shark of European coasts, a harmless, speckled bottom feeder whose curly egg cases wash up on beaches as mermaid's purses. Read the guide →
Fish LC Smallmouth Bass Micropterus dolomieu The smallmouth bass favors cooler, rockier rivers and lakes than its largemouth relative, and its jumping, hard-fighting resistance on a fishing line has made it a favorite among anglers. Read the guide →
Fish LC Smallmouth Buffalo Ictiobus bubalus The smallmouth buffalo can live for over a century, one of the longest-lived freshwater fish in North America, despite being a native species often mistaken for an invasive carp. Read the guide →
Amphibians LC Smallmouth Salamander Ambystoma texanum The smallmouth salamander forms all-female hybrid populations with close relatives, cloning itself generation after generation, almost as unusual as parthenogenetic whiptail lizards. Read the guide →
Amphibians LC Smoky Jungle Frog Leptodactylus pentadactylus One of the biggest frogs in the Americas, the smoky jungle frog screams like a cat when grabbed, oozes an irritating toxic mucus, and raises its young in a floating nest of foam. Read the guide →
Reptiles LC Smooth Earth Snake Virginia valeriae The smooth earth snake spends nearly its life hidden beneath leaf litter and loose soil, a small, secretive burrower most people never encounter despite being common across the eastern United States. Read the guide →
Reptiles LC Smooth Green Snake Opheodrys vernalis The smooth green snake is a gentle green snake so well camouflaged in grass it is far more often heard rustling away than seen, and it turns dull blue-grey after death as its yellow pigment fades. Read the guide →
Amphibians LC Smooth Newt Lissotriton vulgaris The smooth newt is the most common newt in Britain and much of Europe, a small amphibian that spends most of the year on land, breeds in ponds, and courts by fanning water at the female with its tail. Read the guide →
Reptiles LC Smooth Snake Coronella austriaca The smooth snake is a slim, non-venomous European snake with glossy unkeeled scales that constricts lizards nearly as long as itself, and in Britain it is the rarest reptile. Read the guide →
Reptiles LC Smooth Softshell Turtle Apalone mutica The smooth softshell turtle has a leathery, pancake-flat shell free of the bumps and spines found on its close relatives, an adaptation for burying itself almost completely in river sand. Read the guide →
Birds LC Smooth-billed Ani Crotophaga ani The smooth-billed ani nests communally, with multiple females laying their eggs together in a single shared nest raised cooperatively by the whole group. Read the guide →
Reptiles LC Smooth-fronted Caiman Paleosuchus trigonatus The smooth-fronted caiman is a dark, heavily armoured dwarf caiman of Amazon forest streams, a bit larger than Cuvier's dwarf caiman, with a smooth forehead and forest-floor nest mounds. Read the guide →
Invertebrates NE Snail Gastropoda A snail is a shelled gastropod that glides on one muscular foot along a trail of slime, rasps its food with a tongue of thousands of tiny teeth, and can seal itself in its shell to wait out drought. Read the guide →
Fish LC Snail Darter Percina tanasi The snail darter became a household name in the 1970s when its discovery in a Tennessee river halted a federal dam, in one of the most famous endangered species court battles in US history. Read the guide →
Birds NT Snail Kite Rostrhamus sociabilis The snail kite has a bill curved into an almost surgical hook, shaped by evolution around one specific task, extracting a single kind of apple snail cleanly from its shell. Read the guide →
Reptiles NE Snake Serpentes A snake is a legless reptile that evolved from lizards, smells with its tongue, swallows prey whole through jaws joined by stretchy ligament, and hears through its jawbone rather than external ears. Read the guide →
Invertebrates NE Snakefly Raphidioptera The snakefly raises its unusually long, flexible neck and strikes at prey like a tiny snake, a hunting style found in both the predatory larva and the adult. Read the guide →
Fish LC Snakehead Channidae A snakehead is an air-breathing predator from Asia and Africa that survives out of water and wriggles over wet ground, and a few released species have become notorious North American invaders. Read the guide →
Invertebrates NE Snakelocks Anemone Anemonia viridis The snakelocks anemone is a rock-pool anemone with long, wavy, snake-like green tentacles tipped with purple, which cannot retract fully and gets some of its energy from the algae living inside it. Read the guide →
Fish LC Snakeskin Gourami Trichopodus pectoralis The snakeskin gourami carries a mottled, scale-like pattern across its body resembling snake skin, and ranks among the more commercially important farmed gouramis of Southeast Asia. Read the guide →
Fish NE Snapper Lutjanidae A snapper is a sharp-toothed, schooling reef and coastal fish prized as food worldwide, named for the way it snaps its jaws, and often mislabelled on menus where true snapper is scarce. Read the guide →
Reptiles NE Snapping Turtle Chelydridae A snapping turtle is a large, powerful freshwater turtle with a shell too small to hide in, a long striking neck, and a bite it uses to defend itself on land, though in the water it would rather flee. Read the guide →
Birds VU Snares Crested Penguin Eudyptes robustus The Snares crested penguin breeds only on a single small island group closed to the public, nesting under dense forest canopy rather than on open, exposed ground like most other penguins. Read the guide →
Fish LC Snipe Eel Nemichthyidae The snipe eel has jaws so curved they cannot fully close, lined with tiny backward-hooked teeth that snag shrimp by their long antennae like a strip of natural velcro. Read the guide →
Fish LC Snook Centropomus undecimalis The snook is a prized coastal game fish with a distinctive black lateral line running the length of its body, and it begins life as a male before some individuals later transition into females. Read the guide →
Birds LC Snow Bunting Plectrophenax nivalis The snow bunting breeds farther north than almost any other songbird on Earth, nesting within the High Arctic before retreating south each winter to forage across open farmland in large mixed flocks. Read the guide →
Birds LC Snow Goose Anser caerulescens The snow goose gathers in flocks that can exceed a million birds, and grazing pressure from this hyperabundant population has visibly damaged the fragile Arctic tundra it breeds on. Read the guide →
Mammals VU Snow Leopard Panthera uncia The snow leopard is the elusive big cat of Asia's highest mountains, with a metre-long tail for balance and warmth. Learn how it survives thin cold air — and why it can't roar. Read the guide →
Birds LC Snow Petrel Pagodroma nivea The snow petrel is one of only three bird species ever recorded breeding at the South Pole's extreme interior, an entirely white seabird nesting on bare rock hundreds of kilometres from open water. Read the guide →
Fish LC Snowflake Eel Echidna nebulosa The snowflake eel carries blunt, rounded teeth built for crushing crab and shrimp shells rather than piercing fish, a different toolkit from most of its sharp-toothed moray relatives. Read the guide →
Mammals LC Snowshoe Hare Lepus americanus The snowshoe hare moults between brown summer and white winter fur on a schedule triggered by day length, a mismatch increasingly exposing white hares against bare, snowless ground as winters shorten. Read the guide →
Birds LC Snowy Egret Egretta thula The snowy egret hunts by shuffling its bright yellow feet through shallow water to flush hidden prey before striking, a trick that earned those feet the nickname golden slippers. Read the guide →
Birds VU Snowy Owl Bubo scandiacus The snowy owl is a heavy, day-hunting owl of the Arctic tundra that lives and breeds on lemmings. Learn how it survives the cold, why some years it flies far south, and why numbers are falling. Read the guide →
Birds NT Snowy Plover Charadrius nivosus The snowy plover is so pale that its speckled eggs and downy chicks nearly vanish against open sand, a camouflage so effective that beachgoers are the species' single biggest unintentional threat. Read the guide →
Birds LC Sociable Weaver Philetairus socius The sociable weaver builds the largest nest of any bird, a haystack-sized thatched apartment block in a desert tree that houses up to a hundred pairs and lasts for a century. Read the guide →
Fish LC Sockeye Salmon Oncorhynchus nerka The sockeye salmon turns from silver to brilliant scarlet to breed, the male growing a hooked jaw and hump. It navigates thousands of kilometres back to its birth stream, then spawns and dies. Read the guide →
Mammals VU Soemmerring's Gazelle Nanger soemmerringii Soemmerring's gazelle is one of the largest gazelle species, marked by a bold black-and-white facial pattern across the semi-arid grassland of the Horn of Africa. Read the guide →
Birds LC Soft-plumaged Petrel Pterodroma mollis The soft-plumaged petrel is a fast, agile gadfly petrel that breeds across a wide scatter of islands from the tropics to the subantarctic, flying in the sharp zigzag typical of its genus. Read the guide →
Reptiles EN Softshell Turtle Trionychidae A softshell turtle has a flat, leathery shell instead of a hard one and a long snorkel of a snout, and it breathes underwater through its skin and throat, staying buried in river mud for hours. Read the guide →
Invertebrates LC Soldier Beetle Cantharidae The soldier beetle has soft, leathery wing covers unlike the hard shell of most beetles, a texture distinctive enough to earn the whole family the nickname leatherwing. Read the guide →
Mammals EN Solenodon Solenodon paradoxus The solenodon is one of very few venomous mammals, delivering toxic saliva through a groove in its lower teeth. Its lineage split from other mammals around the time of the dinosaurs. Read the guide →
Birds NT Solitary Tinamou Tinamus solitarius The solitary tinamou is one of the largest tinamou species, a shy, forest-dwelling bird of the Atlantic Forest that lives up to its name by spending most of its life alone rather than in groups. Read the guide →
Mammals LC Somali Sengi Galegeeska revoilii The Somali sengi went unrecorded by science for roughly 50 years until a 2020 expedition rediscovered it, revealing a species that had never been rare, just overlooked. Read the guide →
Birds LC Song Sparrow Melospiza melodia The song sparrow varies so dramatically across North America that some three dozen recognized subspecies exist, ranging from pale desert forms to notably large, dark birds of the Aleutian Islands. Read the guide →
Reptiles LC Sonoran Coral Snake Micruroides euryxanthus The Sonoran coral snake spends nearly all its time hidden underground, and when finally cornered, it curls its tail into a tight coil and pops it audibly to startle a predator instead of striking. Read the guide →
Amphibians LC Sonoran Desert Toad Incilius alvarius The Sonoran Desert toad is the largest toad native to the US, and its skin secretes the potent psychedelic 5-MeO-DMT — behind a "toad-licking" myth and a real, damaging harvest for the drug trade. Read the guide →
Reptiles VU Sonoran Desert Tortoise Gopherus morafkai The Sonoran desert tortoise was only recognised as its own species in 2011, split from the Mojave desert tortoise after genetic studies showed the two had evolved separately for millions of years. Read the guide →
Amphibians LC Sonoran Green Toad Anaxyrus retiformis The Sonoran green toad spends most of the year buried underground, emerging only after summer monsoon rains to breed within a matter of days before vanishing again. Read the guide →
Reptiles LC Sonoran Mountain Kingsnake Lampropeltis pyromelana The Sonoran mountain kingsnake wears a bold red, black, and white banded pattern that mimics venomous coral snakes, despite being completely harmless. Read the guide →
Birds EN Sooty Albatross Phoebetria fusca The sooty albatross has entirely dark, sooty-brown plumage and an elegant, synchronised courtship display, nesting alone on cliff ledges rather than in dense colonies like most albatrosses. Read the guide →
Birds LC Sooty Tern Onychoprion fuscatus The sooty tern spends years continuously airborne over open ocean after fledging, some individuals not touching land again until they return to breed, making it one of the most aerial birds alive. Read the guide →
Mammals LC Soprano Pipistrelle Pipistrellus pygmaeus The soprano pipistrelle is a tiny European bat named for its higher-pitched calls, once lumped with the common pipistrelle, that hunts over rivers and lakes and roosts in large summer colonies. Read the guide →
Birds LC Sora Porzana carolina The sora is the most abundant rail in North America, betraying its presence in dense marsh vegetation with a distinctive descending whinny few visitors ever manage to trace back to the bird itself. Read the guide →
Mammals LC South African Fur Seal Arctocephalus pusillus The South African fur seal forms some of the largest fur seal colonies in the world, tens of thousands strong on one stretch of coast, a robust species split into populations off Africa and Australia. Read the guide →
Mammals LC South American Fur Seal Arctocephalus australis The South American fur seal was hunted so intensively for its dense, valuable pelt that populations collapsed by over 90 percent, only recovering after commercial sealing finally ended in the region. Read the guide →
Mammals LC South American Gray Fox Lycalopex griseus The South American gray fox, known locally as the chilla, is the most common wild fox across Patagonia, once hunted extensively for a fur trade that has since sharply declined. Read the guide →
Mammals LC South American Sea Lion Otaria flavescens The South American sea lion is named for the thick, mane-like fur surrounding a mature male's neck and shoulders, a large, powerfully built pinniped found along much of the coastline of South America. Read the guide →
Birds LC South American Tern Sterna hirundinacea The South American tern dives for small fish along southern coastlines, closely resembling the Arctic and common terns but staying resident within the Southern Hemisphere year-round. Read the guide →
Amphibians LC South Carolina Slimy Salamander Plethodon variolatus The South Carolina slimy salamander occupies its own narrow strip of the old slimy salamander complex, one of more than a dozen genetically distinct species revealed when the group was split apart. Read the guide →
Amphibians CR South China Giant Salamander Andrias sligoi The South China giant salamander is the largest amphibian on Earth, historically nearly two metres long. Overhunting for luxury food has left it all but extinct in the wild. Read the guide →
Birds LC South Georgia Diving-petrel Pelecanoides georgicus The South Georgia diving-petrel is the smallest of the diving-petrel species, flying underwater with rapidly whirring wings in pursuit of the tiny planktonic prey it feeds on. Read the guide →
Birds LC South Georgia Pintail Anas georgica georgica The South Georgia pintail is one of the few ducks adapted to a sub-Antarctic island environment, scavenging seal carcasses and seabird eggs alongside a more typical diet of plants and invertebrates. Read the guide →
Birds NT South Georgia Pipit Anthus antarcticus The South Georgia pipit is the only songbird that breeds south of the Antarctic Convergence, nearly wiped out by introduced rats before a record-breaking eradication project brought it back. Read the guide →
Birds LC South Georgia Shag Leucocarbo georgianus The South Georgia shag is endemic to a single remote island group, diving to considerable depths for bottom-dwelling fish and displaying bright orange caruncles during the breeding season. Read the guide →
Birds LC South Polar Skua Stercorarius maccormicki The south polar skua has been recorded closer to the South Pole than any other bird, an aggressive predator and scavenger that steals food from other seabirds and preys on penguin eggs and chicks. Read the guide →
Reptiles LC Southeastern Crowned Snake Tantilla coronata The southeastern crowned snake is a tiny, secretive burrower with mild venom delivered from rear teeth, just barely enough to subdue the small centipedes and insects that make up its diet. Read the guide →
Reptiles LC Southeastern Five-Lined Skink Plestiodon inexpectatus The southeastern five-lined skink looks so close to two of its relatives that telling all three apart in the field usually comes down to counting scales. Read the guide →
Reptiles LC Southern Alligator Lizard Elgaria multicarinata The southern alligator lizard grips branches with a genuinely prehensile tail, almost like an extra limb, and will happily settle into a suburban garden as readily as open California woodland. Read the guide →
Amphibians LC Southern Appalachian Salamander Plethodon teyahalee The southern Appalachian salamander breathes entirely through its skin, relying on cool, damp mountain forest so completely that it never strays far from moist leaf litter or rotting logs. Read the guide →
Mammals LC Southern Bottlenose Whale Hyperoodon planifrons The southern bottlenose whale is a deep-diving beaked whale found in a circumpolar band around Antarctica, closely related to its North Atlantic counterpart but restricted to the far south. Read the guide →
Mammals NT Southern Brown Bandicoot Isoodon obesulus The southern brown bandicoot has declined sharply across parts of its range, squeezed between introduced predators and the loss of the dense coastal heathland it shelters in. Read the guide →
Birds LC Southern Carmine Bee-eater Merops nubicoides The southern carmine bee-eater is a brilliant red African bird that nests in huge colonies in riverbanks, catches bees in flight, and rides on bustards and antelopes to flush insects. Read the guide →
Birds LC Southern Cassowary Casuarius casuarius The southern cassowary is a huge flightless rainforest bird with a bony head casque and dagger-clawed feet. It is the only animal that can spread some large rainforest seeds. Read the guide →
Amphibians LC Southern Chorus Frog Pseudacris nigrita The southern chorus frog calls from shallow, grassy ditches and temporary ponds across the southeastern coastal plain, carrying three dark stripes down an otherwise small, unremarkable body. Read the guide →
Amphibians CR Southern Corroboree Frog Pseudophryne corroboree The southern corroboree frog is a striking yellow-and-black Australian alpine frog that makes its own poison. Fewer than 50 survive in the wild, held from extinction only by captive colonies. Read the guide →
Amphibians NT Southern Crawfish Frog Lithobates areolatus areolatus The southern crawfish frog spends nearly all its life inside an abandoned crayfish burrow, emerging mainly to breed, a level of dependence on another animal's construction work rare among frogs. Read the guide →
Amphibians LC Southern Cricket Frog Acris gryllus The southern cricket frog produces a call so similar to two pebbles struck together that it gives the entire cricket frog group its name, despite being a true frog with no relation to crickets. Read the guide →
Amphibians EN Southern Dusky Salamander Desmognathus auriculatus The southern dusky salamander vanished from most of its range for reasons only partly understood, one of the more mysterious amphibian declines in the southeastern US. Read the guide →
Mammals LC Southern Elephant Seal Mirounga leonina The southern elephant seal is the largest seal species on Earth, with bulls capable of exceeding four tonnes, and can dive deeper and longer than almost any other marine mammal in search of squid. Read the guide →
Mammals LC Southern Flying Squirrel Glaucomys volans The southern flying squirrel often nests in winter huddles of a dozen or more individuals, a nocturnal glider that shares body heat with unrelated squirrels rather than facing cold nights alone. Read the guide →
Birds LC Southern Fulmar Fulmarus glacialoides The southern fulmar breeds in enormous colonies on cliffs around the Antarctic continent itself, defending its nest by spitting a foul-smelling stomach oil at any threat that comes too close. Read the guide →
Birds LC Southern Giant Petrel Macronectes giganteus The southern giant petrel breeds further south than the northern giant petrel, scavenging seal and penguin carcasses with the same massive hooked bill, distinguished only by a greenish bill tip. Read the guide →
Birds VU Southern Ground Hornbill Bucorvus leadbeateri The southern ground hornbill is a turkey-sized black bird with a red face that hunts snakes and tortoises on foot. It lives up to 70 years and raises a chick barely once a decade. Read the guide →
Mammals LC Southern Hairy-Nosed Wombat Lasiorhinus latifrons The southern hairy-nosed wombat digs sprawling multi-entrance burrow systems across arid grassland, sharing tunnels with a whole community of wombats nearby. Read the guide →
Invertebrates LC Southern Hawker Aeshna cyanea The southern hawker is a large, inquisitive dragonfly with apple-green and blue markings that hunts along woodland paths and garden hedges and will hover to inspect passing people. Read the guide →
Reptiles VU Southern Hognose Snake Heterodon simus The southern hognose snake spreads a cobra-like hood, hisses dramatically, and then plays dead if the bluff fails, despite being completely harmless. Read the guide →
Invertebrates LC Southern King Crab Lithodes santolla The southern king crab is a large, commercially important crustacean of Patagonia and Tierra del Fuego, more closely related to hermit crabs than to true crabs despite its imposing size. Read the guide →
Birds LC Southern Lapwing Vanellus chilensis The southern lapwing is one of the most conspicuous and vocal birds of open South American habitat, using loud alarm calls and aggressive aerial dives to defend its nest against intruders. Read the guide →
Amphibians LC Southern Leopard Frog Lithobates sphenocephalus The southern leopard frog can leap an impressive distance in a single bound, a spotted, pointed-nosed frog common across the southeastern United States that often strays well away from water. Read the guide →
Mammals LC Southern Mountain Cavy Microcavia australis The southern mountain cavy is a small, highly social relative of the guinea pig, living in burrow colonies across the arid scrubland and desert of Patagonia and central Argentina. Read the guide →
Mammals VU Southern Pudu Pudu puda The southern pudu is one of the smallest deer species in the world, a shy, solitary browser hiding within the dense undergrowth of southern Chilean and Argentine temperate rainforest. Read the guide →
Fish LC Southern Redbelly Dace Chrosomus erythrogaster The southern redbelly dace turns a brilliant, fiery red along its belly during breeding season, one of the most vivid colour transformations of any small North American minnow. Read the guide →
Mammals LC Southern Reedbuck Redunca arundinum The southern reedbuck relies on a piercing whistled alarm call and tall reedbeds for cover, a shy grassland antelope rarely seen far from water. Read the guide →
Mammals LC Southern Right Whale Eubalaena australis The southern right whale has recovered strongly since commercial whaling ended, now numbering in the tens of thousands, a success story contrasting sharply with its critically endangered relative. Read the guide →
Mammals LC Southern Right Whale Dolphin Lissodelphis peronii The southern right whale dolphin is the Southern Hemisphere counterpart to a similarly fin-free North Pacific dolphin, a sleek, boldly patterned swimmer of cold circumpolar waters near Antarctica. Read the guide →
Mammals EN Southern River Otter Lontra provocax The southern river otter is an Endangered species of southern Chile and Argentina, hunted heavily for its fur in the twentieth century and now surviving in fragmented river and coastal populations. Read the guide →
Birds VU Southern Rockhopper Penguin Eudyptes chrysocome The southern rockhopper is one of the smallest crested penguins, with spiky yellow eyebrow plumes, and it climbs sea cliffs by jumping up them with both feet together instead of walking. Read the guide →
Birds VU Southern Royal Albatross Diomedea epomophora The southern royal albatross rivals the wandering albatross for the largest wingspan of any living bird, distinguished from its closest relative by a solid black cutting edge along its bill. Read the guide →
Birds LC Southern Screamer Chauna torquata The southern screamer produces a trumpeting call audible for kilometres, a large, goose-like bird armed with sharp spurs on its wings for territorial combat. Read the guide →
Mammals LC Southern Tamandua Tamandua tetradactyla The southern tamandua is a medium-sized anteater marked by a distinctive black vest pattern, equally at home climbing trees or foraging on the ground. Read the guide →
Amphibians LC Southern Toad Anaxyrus terrestris The southern toad is a common amphibian of the southeastern United States, identified by bony ridges and knobs on its head, and it digs backward into sandy soil to escape heat and predators. Read the guide →
Amphibians NT Southern Torrent Salamander Rhyacotriton variegatus The southern torrent salamander is the southernmost of four cold-water species, unable to tolerate water warmer than the coldest mountain streams of northern California and southwestern Oregon. Read the guide →
Amphibians LC Southern Two-Lined Salamander Eurycea cirrigera The southern two-lined salamander occupies the warmer, lower share of a species complex across eastern North America, a common streamside amphibian easily mistaken for nearly identical relatives. Read the guide →
Reptiles LC Southern Watersnake Nerodia fasciata The southern watersnake is frequently mistaken for a venomous cottonmouth and killed on sight, despite being harmless and playing an important role controlling fish and amphibian populations. Read the guide →
Mammals LC Sowerby's Beaked Whale Mesoplodon bidens Sowerby's beaked whale was the first member of its genus formally described, based on a specimen stranded in Scotland two centuries ago, one of the more obscure mammals of the North Atlantic. Read the guide →
Mammals DD Spade-toothed Whale Mesoplodon traversii The spade-toothed whale is considered one of the rarest and least known mammal species on Earth, never confirmed alive at sea and known only from a handful of stranded specimens. Read the guide →
Amphibians NE Spadefoot Toad Pelobatoidea A spadefoot toad digs backward into dry soil with a hard spade on each hind foot, waits out months of drought underground, and breeds in a frantic rush the night heavy rain arrives. Read the guide →
Birds LC Spangled Cotinga Cotinga cayana The spangled cotinga is a brilliant turquoise-blue bird of the Amazon canopy, males marked by a deep purple throat patch, yet easily overlooked despite the vivid colour. Read the guide →
Invertebrates LC Spanish Dancer Hexabranchus sanguineus The Spanish dancer is the largest sea slug in the world, a scarlet reef animal that usually crawls but can unfurl its body into a rippling skirt and swim through open water like a flamenco dress. Read the guide →
Invertebrates NE Spanish Shawl Nudibranch Flabellina iodinea The Spanish shawl nudibranch pairs a deep purple body with bright orange finger-like projections, storing stinging cells stolen from the hydroids it eats for its own defense. Read the guide →
Birds LC Sparkling Violetear Colibri coruscans The sparkling violetear flares iridescent violet patches on the sides of its head during territorial disputes, one of the most common and aggressive hummingbirds across the Andes. Read the guide →
Birds NE Sparrow Passeridae and Passerellidae A sparrow is a small, streaky, seed-eating songbird, and the name covers two unrelated families, the Old World sparrows such as the house sparrow and the New World sparrows of the Americas. Read the guide →
Reptiles LC Speckled Kingsnake Lampropeltis holbrooki The speckled kingsnake is covered in so many yellow flecks that it earned the nickname salt-and-pepper snake, and like other kingsnakes it is largely immune to rattlesnake venom. Read the guide →
Reptiles LC Speckled Rattlesnake Crotalus mitchellii The speckled rattlesnake often closely matches the exact rock color of the ground it rests on, with populations ranging from pale gray to pink and reddish depending on local terrain. Read the guide →
Reptiles VU Speckled Tortoise Homopus signatus The speckled tortoise is the smallest tortoise species in the world, small enough to fit in a human hand, and it survives South Africa's dry rocky hillsides by wedging into narrow crevices. Read the guide →
Invertebrates LC Speckled Wood Pararge aegeria The speckled wood is a dappled brown woodland butterfly whose males defend sunbeams in territorial duels, and it can overwinter as either a caterpillar or a chrysalis. Read the guide →
Mammals VU Spectacled Bear Tremarctos ornatus The spectacled bear is South America's only bear species, named for the pale, mask-like markings around its eyes that vary uniquely from one individual to the next. Read the guide →
Reptiles LC Spectacled Caiman Caiman crocodilus The spectacled caiman is the most abundant and adaptable crocodilian in the world, named for a bony ridge between its eyes like a pair of glasses. Escaped pets have established it in southern Florida. Read the guide →
Birds LC Spectacled Duck Speculanas specularis The spectacled duck nests in tree cavities along forested Patagonian streams, unlike most ducks, males marked by a distinctive pale ring of feathers resembling a pair of spectacles. Read the guide →
Mammals EN Spectacled Flying Fox Pteropus conspicillatus The spectacled flying fox gets its name from pale fur rings around its eyes, an Endangered rainforest species that has suffered mass deaths during extreme heatwaves. Read the guide →
Birds LC Spectacled Owl Pulsatrix perspicillata The spectacled owl is named for bold white markings around its eyes, and its juveniles look almost entirely different from adults, taking years to grow into adult plumage. Read the guide →
Birds VU Spectacled Petrel Procellaria conouri The spectacled petrel breeds only on a single remote South Atlantic island, its pale eye markings resembling spectacles against otherwise dark plumage. Read the guide →
Mammals DD Spectacled Porpoise Phocoena dioptrica The spectacled porpoise has a bold black eye patch ringed in white that resembles a pair of spectacles, one of the least frequently observed marine mammals of the cold Southern Hemisphere waters. Read the guide →
Amphibians LC Spectacled Salamander Salamandrina perspicillata The spectacled salamander is a small matte-black Italian amphibian with a pale mask between its eyes. Threatened, it curls its tail up to flash a hidden crimson underside, then plays dead. Read the guide →
Birds LC Spectacled Tyrant Hymenops perspicillatus The spectacled tyrant perches conspicuously near water, males marked by a bright yellow eye-ring and wing patch standing out sharply against otherwise black plumage. Read the guide →
Mammals NT Spectral Bat Vampyrum spectrum The spectral bat is the largest carnivorous bat in the Americas, hunting birds and other bats in complete stealth despite a fearsome name that wrongly suggests it drinks blood. Read the guide →
Mammals EN Speke's Gazelle Gazella spekei Speke's gazelle is the smallest gazelle species in the world, with a strange inflatable nasal flap that amplifies its alarm snort into a loud, resonant honk. Read the guide →
Mammals VU Sperm Whale Physeter macrocephalus The sperm whale is the largest toothed predator on Earth and has the biggest brain of any animal. It dives 2 km down for an hour to hunt giant squid using the most powerful sonar in nature. Read the guide →
Invertebrates LC Spicebush Swallowtail Papilio troilus The spicebush swallowtail caterpillar folds a leaf into a protective shelter and paints two large false eyespots on its body, transforming into a convincing small-snake decoy by day. Read the guide →
Invertebrates NE Spider Araneae A spider is an eight-legged hunter that builds with silk, digests its prey outside its body, and in almost every species carries venom, though very few can seriously harm a person. Read the guide →
Invertebrates LC Spider Conch Lambis lambis The spider conch grows long, curved shell spines resembling spider legs, and uses a specialised claw-shaped operculum to flip itself upright and leap away from approaching predators. Read the guide →
Mammals EN Spider Monkey Ateles geoffroyi The spider monkey swings through the rainforest canopy on long limbs and a prehensile tail that works as a fifth hand, complete with a hairless, fingerprint-ridged gripping pad. It rarely comes down. Read the guide →
Reptiles CR Spider Tortoise Pyxis arachnoides The spider tortoise carries a shell patterned with radiating yellow lines on dark ground, a web-like design that camouflages it among Madagascar's dry coastal forest leaf litter. Read the guide →
Reptiles DD Spider-tailed Horned Viper Pseudocerastes urarachnoides The tip of this Iranian viper's tail mimics a spider, a bulbous knob fringed with leg-like scales that it twitches to lure insect-eating birds into striking range. Read the guide →
Fish LC Spined Loach Cobitis taenia The spined loach is a slim, sand-dwelling little fish with a hidden spine below each eye and six barbels, which buries itself by day and sifts the bottom for food by night. Read the guide →
Fish EN Spinetail Devil Ray Mobula mobular The spinetail devil ray is a smaller cousin of the manta that gathers in huge schools and launches itself metres clear of the water, landing with a loud crack. Why they leap is still debated. Read the guide →
Mammals LC Spinifex Hopping-mouse Notomys alexis The spinifex hopping-mouse is a tiny kangaroo-like rodent of Australia's sand deserts that hops on its hind legs, shelters in group burrows, and can live without drinking. Read the guide →
Mammals LC Spinner Dolphin Stenella longirostris The spinner dolphin leaps clear of the water and rotates its body several times in one jump, a spectacular display whose exact purpose researchers still debate, from signalling to shedding parasites. Read the guide →
Reptiles NE Spiny Bush Viper Atheris hispida The spiny bush viper is a small African tree viper whose strongly keeled, upturned scales stick out to give it a bristly, almost dragon-like coat. It ambushes frogs and small mammals at night. Read the guide →
Invertebrates NE Spiny Flower Mantis Pseudocreobotra wahlbergii The spiny flower mantis carries a bold eyespot pattern on its wings, flashed suddenly to startle predators, while its nymphs mimic flowers to ambush visiting pollinators. Read the guide →
Invertebrates LC Spiny Leaf Insect Extatosoma tiaratum The spiny leaf insect's young mimic ants for protection before growing into an adult that curls its abdomen like a scorpion, despite being completely harmless the entire time. Read the guide →
Reptiles LC Spiny Softshell Turtle Apalone spinifera The spiny softshell turtle has a flat, leathery, pancake-like shell with no hard scutes and a long snorkel snout. It breathes underwater through its skin and throat and buries itself in river sand. Read the guide →
Invertebrates NE Spiny Spider Crab Maja brachydactyla The spiny spider crab is a large, long-legged, spiny-shelled crab of the north-eastern Atlantic that decorates itself with seaweed and sponges and gathers in huge piles to moult. Read the guide →
Reptiles VU Spiny-tailed Lizard Uromastyx aegyptia The spiny-tailed lizard swings a thick, armour-ringed tail like a club when threatened. Almost entirely vegetarian as an adult, it survives scorching desert sand while drinking almost no water. Read the guide →
Amphibians LC Splash-Back Poison Frog Ranitomeya variabilis The splash-back poison frog carries a pattern so distinctive that a completely unrelated frog species has evolved to copy it, a small, toxic Amazonian amphibian at the heart of a real mimicry story. Read the guide →
Amphibians NT Splendid Leaf Frog Cruziohyla calcarifer The splendid leaf frog reveals hidden orange and blue on its flanks and thighs only when it leaps, an instant flash-and-vanish display that startles predators just long enough for it to disappear. Read the guide →
Invertebrates LC Spongy Moth Lymantria dispar The spongy moth was deliberately imported for a failed silk-farming experiment in the 1860s, escaped captivity, and has been defoliating North American forests in cyclical outbreaks ever since. Read the guide →
Birds LC Spot-flanked Gallinule Porphyriops melanops The spot-flanked gallinule is a small, secretive marsh bird of South America, identified by white-spotted flanks against otherwise dark plumage. Read the guide →
Birds LC Spot-winged Pigeon Patagioenas maculosa The spot-winged pigeon ranges from lowland Patagonian scrub to high Andean valleys, marked by a distinctive row of white spots across its folded wing feathers. Read the guide →
Fish LC Spotfin Shiner Cyprinella spiloptera The spotfin shiner tolerates murkier, more disturbed water than many of its minnow relatives, often becoming one of the most common small fish in streams degraded enough to push pickier species out. Read the guide →
Birds LC Spotted Antbird Hylophylax naevioides The spotted antbird will follow army ant swarms when they pass by but, unlike some relatives, can survive perfectly well without ever finding one. Read the guide →
Fish LC Spotted Bass Micropterus punctulatus The spotted bass fills the middle ground between its two more famous relatives, favouring rockier, moving water over the largemouth's weedy lakes while skipping the smallmouth's coldest streams. Read the guide →
Mammals LC Spotted Bat Euderma maculatum The spotted bat carries ears nearly as long as its own body and calls at a pitch low enough for humans to hear unaided, a rare trait among echolocating bats. Read the guide →
Amphibians LC Spotted Chirping Frog Eleutherodactylus guttilatus The spotted chirping frog skips the tadpole stage entirely, laying eggs on land that hatch directly into froglets, freeing it from any dependence on ponds or streams to complete its life cycle. Read the guide →
Amphibians LC Spotted Chorus Frog Pseudacris clarkii The spotted chorus frog carries bolder, better-defined dark blotches than most of its chorus frog relatives, calling from temporary pools scattered across south-central grassland and farmland. Read the guide →
Birds LC Spotted Crake Porzana porzana The spotted crake wears a body dusted with fine white spots and streaks, camouflage that helps it vanish almost completely into the dense marsh vegetation it rarely leaves. Read the guide →
Amphibians LC Spotted Dusky Salamander Desmognathus conanti The spotted dusky salamander carries light blotches along its back, a marking more pronounced than in many of its closely related dusky salamander cousins found across the same southeastern streams. Read the guide →
Fish EN Spotted Eagle Ray Aetobatus narinari The spotted eagle ray is a graceful, leopard-spotted ray that "flies" through open water, digs clams and conch out of the seabed with a duck-like snout, and leaps clear of the surface in big jumps. Read the guide →
Fish LC Spotted Gar Lepisosteus oculatus The spotted gar wears a body armored in thick, diamond-shaped scales largely unchanged for tens of millions of years, drifting motionless in weedy shallows until a fish swims too close. Read the guide →
Fish CR Spotted Handfish Brachionichthys hirsutus The spotted handfish walks across the seabed on fins shaped like little hands instead of swimming. It lives in one Australian estuary and was the first marine fish listed as Critically Endangered. Read the guide →
Mammals LC Spotted Hyena Crocuta crocuta The spotted hyena is Africa's most successful large predator — a skilled pack hunter, not just a scavenger, living in female-led clans of up to 130, with bone-crushing jaws and an eerie call. Read the guide →
Invertebrates NE Spotted Lanternfly Lycorma delicatula The spotted lanternfly is an Asian planthopper, not a fly, that has invaded the eastern United States, where it drains sap from grapevines and trees and hitchhikes as egg masses on cars. Read the guide →
Mammals LC Spotted Linsang Prionodon pardicolor The spotted linsang shares its closest relative's surprising kinship with true cats, a bold, dark-spotted sister species to the banded linsang found across the forests of mainland Southeast Asia. Read the guide →
Birds NT Spotted Owl Strix occidentalis The spotted owl depends on old-growth forest so specific that its decline became a defining conservation battle, and a competing relative's arrival has made its situation more precarious still. Read the guide →
Fish LC Spotted Ratfish Hydrolagus colliei The spotted ratfish has large, glowing green eyes and a long, tapering tail, a chimaera found along the Pacific coast of North America that rises into shallow water at night to feed. Read the guide →
Fish LC Spotted Ray Raja montagui The spotted ray is a small, sandy-brown ray of north-eastern Atlantic seabeds marked with many small dark spots and rounded wing patches, one of the commonest rays around Britain and Ireland. Read the guide →
Amphibians LC Spotted Salamander Ambystoma maculatum The spotted salamander lives underground most of the year, emerges on a few rainy spring nights to breed in vernal pools, and hosts algae inside its own cells — unique among vertebrates. Read the guide →
Birds LC Spotted Sandpiper Actitis macularius The spotted sandpiper reverses the usual roles seen in most birds, with females competing for mates and males left to incubate the eggs and raise the young almost entirely on their own. Read the guide →
Mammals LC Spotted Seal Phoca largha The spotted seal gives birth on stable pack ice rather than in the water, timing its pupping season closely with the seasonal formation of sea ice across the North Pacific and Arctic it depends on. Read the guide →
Fish LC Spotted Seatrout Cynoscion nebulosus The spotted seatrout is marked with black spots scattered across its back and fins, setting it apart from other seatrout, and can die off in sudden mass numbers during hard cold snaps. Read the guide →
Fish LC Spotted Sucker Minytrema melanops The spotted sucker carries a dark spot at the base of nearly every scale, together forming faint rows that run the length of its body. Read the guide →
Fish LC Spotted Sunfish Lepomis punctatus The spotted sunfish carries neat rows of small dark spots along its sides, favouring the quiet, vegetated waters and sluggish ditches of the southeastern coastal plain. Read the guide →
Birds LC Spotted Towhee Pipilo maculatus The spotted towhee announces itself by scratching through dry leaf litter with both feet at once, a double-footed hop-and-scratch that gives away its presence before the bird comes into view. Read the guide →
Reptiles EN Spotted Turtle Clemmys guttata A spotted turtle is a small black semi-aquatic turtle of eastern North America dotted with bright yellow spots, once common in wet meadows and now Endangered from wetland loss and collection. Read the guide →
Mammals NT Spotted-Tailed Quoll Dasyurus maculatus The spotted-tailed quoll is the largest carnivorous marsupial left on mainland Australia, the only quoll species spotted on its tail as well as its body. Read the guide →
Birds NT Sprague's Pipit Anthus spragueii Sprague's pipit delivers its courtship song while circling far overhead, sometimes climbing hundreds of feet above the prairie and staying aloft for close to an hour before dropping back down. Read the guide →
Invertebrates LC Spring Azure Celastrina ladon The spring azure is often the first butterfly of the year, emerging from its chrysalis on the first warm days of spring, well before most other butterflies have completed their winter dormancy. Read the guide →
Amphibians LC Spring Peeper Pseudacris crucifer The spring peeper is a thumbnail-sized tree frog whose shrill mating chorus is the classic sound of early spring across eastern North America. It survives winter with much of its body frozen solid. Read the guide →
Amphibians LC Spring Salamander Gyrinophilus porphyriticus The spring salamander is a large pink lungless salamander of cold Appalachian streams that breathes through its skin and hunts other salamanders, including its own kind. Read the guide →
Mammals LC Springbok Antidorcas marsupialis The springbok performs a stiff-legged leaping display called pronking, a South African antelope famous enough to lend its name to the country's national rugby team. Read the guide →
Mammals LC Springhare Pedetes capensis The springhare is a rabbit-sized African rodent that hops on powerful hind legs like a tiny kangaroo, clearing over two metres a bound. Its fur glows pink and orange under UV, discovered in 2021. Read the guide →
Invertebrates LC Springtail Collembola A springtail is a tiny six-legged animal, not quite an insect, that lives by the billion in soil recycling dead matter, and can catapult itself with a spring-loaded tail under the body. Read the guide →
Reptiles VU Spur-thighed Tortoise Testudo graeca The spur-thighed tortoise, or Greek tortoise, is a domed, yellow-and-black Mediterranean tortoise with spurs on its thighs, listed as Vulnerable because of habitat loss and pet-trade collection. Read the guide →
Fish VU Spurdog Squalus acanthias The spurdog is a small, grey, white-spotted shark with a venomous spine in front of each dorsal fin that hunts in packs, carries its young for nearly two years, and has been devastated by fishing. Read the guide →
Invertebrates LC Squash Bee Peponapis The squash bee begins foraging before sunrise, timed exactly to when squash and pumpkin flowers first open, and males often spend the night sleeping curled up inside a wilting flower. Read the guide →
Invertebrates LC Squash Bug Anasa tristis The squash bug lays distinctive bronze egg clusters on the undersides of leaves, and both nymphs and adults can cause an entire squash vine to wilt within days. Read the guide →
Invertebrates LC Squat Lobster Galatheoidea The squat lobster looks like a true lobster but is actually more closely related to hermit crabs, a flattened, long-clawed scavenger found from shallow reefs to deep hydrothermal vents. Read the guide →
Invertebrates NE Squid Teuthida A squid is a fast, streamlined cephalopod that jets through open water; it has the largest eyes of any animal, and the giant and colossal species are the largest invertebrates alive. Read the guide →
Mammals NE Squirrel Sciuridae A squirrel belongs to the rodent family Sciuridae — tree squirrels, ground squirrels, chipmunks, marmots, flying squirrels — and a nut-hoarder plants forests by forgetting where it buried them. Read the guide →
Birds LC Squirrel Cuckoo Piaya cayana The squirrel cuckoo moves through branches with a long reddish-brown tail trailing behind it, resembling a squirrel more than a typical bird as it hunts for insects. Read the guide →
Amphibians LC Squirrel Treefrog Hyla squirella The squirrel treefrog changes color across greens and browns depending on temperature and humidity, and earned the folk nickname rain frog for calling just before a storm arrives. Read the guide →
Invertebrates NT Stag Beetle Lucanidae A stag beetle is a large woodland beetle in which the male grows enormous antler-like jaws, used to wrestle rival males, while the grubs spend years eating rotten wood underground. Read the guide →
Invertebrates CR Staghorn Coral Acropora cervicornis Staghorn coral grows faster than almost any other reef-building coral, branching into antler-like thickets that once covered vast stretches of Caribbean reef now reduced to a fraction. Read the guide →
Invertebrates NE Stalked Jellyfish Stauromedusae The stalked jellyfish spends its entire adult life attached to seaweed or rock by a stalk, a trumpet-shaped relative of true jellyfish that never swims freely through open water. Read the guide →
Birds LC Standard-winged Nightjar Caprimulgus longipennis In the breeding season the male standard-winged nightjar grows one flight feather on each wing into a bare shaft nearly twice his body length, tipped with a feathered flag he trails in display flight. Read the guide →
Mammals LC Star-Nosed Mole Condylura cristata The star-nosed mole has 22 pink fleshy tentacles ringing its snout — the most sensitive touch organ known — and identifies and eats prey in about a fifth of a second, faster than any other mammal. Read the guide →
Invertebrates NE Starfish Asteroidea A starfish is a brainless, bloodless sea animal that walks on hundreds of water-powered tube feet, pushes its stomach out through its mouth to digest prey, and can regrow a lost arm. Read the guide →
Fish LC Stargazer Uranoscopidae The stargazer buries itself in the seabed with only its upward-facing eyes and mouth showing, waiting to engulf prey overhead. Several species deliver both a venomous spine and an electric shock. Read the guide →
Fish LC Starhead Topminnow Fundulus dispar The starhead topminnow carries a small star-shaped patch of light scales between its eyes, a marking that gives the species its name and helps separate it from similarly shaped topminnow relatives. Read the guide →
Birds NE Starling Sturnidae A starling is a stocky, glossy, social songbird that flocks in the thousands, weaves mimicry into a rambling song, and, as the common starling, has been spread worldwide as an invader. Read the guide →
Fish VU Starry Ray Amblyraja radiata The starry ray, or thorny skate, is a small, spine-covered ray of cold North Atlantic seas whose back and tail bristle with star-shaped thorns, once one of the most abundant skates in the region. Read the guide →
Mammals LC Steenbok Raphicerus campestris The steenbok survives without ever needing to drink water and deliberately buries its own dung, a small solitary antelope that relies on stillness rather than speed to avoid predators. Read the guide →
Mammals NT Steller Sea Lion Eumetopias jubatus The Steller sea lion is the largest of all sea lion species, a massive, deep-roaring seal whose population crash across parts of Alaska in the late 20th century remains only partly understood. Read the guide →
Birds LC Steller's Jay Cyanocitta stelleri Steller's jay is the western counterpart to the blue jay, sharing the same bold personality and a prominent crest, yet separated by a divide that keeps the two species from ever really overlapping. Read the guide →
Birds VU Steller's Sea Eagle Haliaeetus pelagicus The Steller's sea eagle is the heaviest eagle in the world, built around a massive orange bill for tearing into salmon along icy Russian coasts. Females can outweigh a bald eagle by nearly double. Read the guide →
Fish LC Sterbai Corydoras Corydoras sterbai The sterbai corydoras tolerates noticeably warmer water than most of its relatives, making it one of the few corydoras species that can comfortably share a tank with heat-loving fish like discus. Read the guide →
Invertebrates NE Stick Insect Phasmatodea Stick insects are twig-shaped plant-eaters that hide by looking exactly like the branch they sit on, include the longest insect in the world, and in many species breed without any males at all. Read the guide →
Fish NE Stingray Myliobatoidei A stingray is a flattened relative of the shark that ripples its fins along the sea floor, and it carries venomous barbed tail spines used only in defence, when a predator or a foot presses on it. Read the guide →
Invertebrates LC Stink Bug Pentatomidae The stink bug releases a pungent defensive odor from glands on its abdomen when disturbed, and one invasive species has become notorious for gathering by the thousands inside houses each autumn. Read the guide →
Birds VU Stitchbird Notiomystis cincta The stitchbird is the only bird species known to regularly mate face-to-face, a small New Zealand honeyeater relative that survives today only through intensive translocation to predator-free islands. Read the guide →
Mammals LC Stoat Mustela erminea The stoat is a slender, hyperactive predator barely wider than the burrows it hunts in, able to kill a rabbit five times its weight. In the north it turns white in winter — the ermine of royal robes. Read the guide →
Fish LC Stone Loach Barbatula barbatula The stone loach is a slender, mottled, nocturnal bottom fish with six whisker-like barbels, which hides under stones by day in clean streams and rivers across Europe and Asia. Read the guide →
Fish LC Stonecat Noturus flavus The stonecat delivers a genuinely painful sting from venom glands at the base of its pectoral and dorsal spines, a defense unusual among the otherwise mild madtom catfish it belongs to. Read the guide →
Fish NE Stonefish Synanceia A stonefish is a lumpy ambush predator of Indo-Pacific shallows that looks just like an algae-covered rock, and the 13 spines along its back carry the most painful venom of any fish. Read the guide →
Invertebrates LC Stonefly Plecoptera A stonefly is an ancient, flat-winged aquatic insect that crawls out of the water to moult on rocks and streamside plants, and with mayflies and caddisflies it is a standard measure of clean water. Read the guide →
Fish LC Stoplight Loosejaw Malacosteus niger The stoplight loosejaw hunts with red light invisible to almost everything around it and a jaw so reduced it has barely any floor left, letting it snap shut on prey with almost no resistance. Read the guide →
Birds NE Stork Ciconiidae A stork is a tall, heavy-billed bird that soars on broad wings, is nearly voiceless so it talks by clattering its bill, and in Europe nests for generations on village chimneys. Read the guide →
Birds LC Stork-billed Kingfisher Pelargopsis capensis The stork-billed kingfisher carries a massive, thick red bill more reminiscent of a stork, a powerful tool that lets it take prey far beyond the small fish most kingfishers rely on. Read the guide →
Birds LC Storm-Petrel Hydrobatidae A storm-petrel appears to walk on water, pattering its feet across the surface while fluttering just above the waves to snatch tiny prey, a habit that earned the family a name tied to Saint Peter. Read the guide →
Mammals LC Strap-Toothed Whale Mesoplodon layardii The strap-toothed whale is the largest species in its genus, and adult males grow teeth so long they curl over the upper jaw and restrict how wide the mouth opens, an extraordinary trade-off. Read the guide →
Mammals NT Straw-Colored Fruit Bat Eidolon helvum The straw-colored fruit bat forms the largest mammal migration on Earth by number of individuals, millions converging on a single Zambian forest each year. Read the guide →
Amphibians LC Strawberry Poison Frog Oophaga pumilio A strawberry poison frog is a thumbnail-sized Central American frog, often red with blue legs, whose mother carries her tadpoles up a tree one by one and feeds each on her unfertilised eggs. Read the guide →
Amphibians LC Strawberry Poison-dart Frog Oophaga pumilio The strawberry poison-dart frog carries its tadpoles one at a time up into tree-hole pools and feeds each one on unfertilised eggs for weeks. It comes in dozens of colour forms across a small range. Read the guide →
Birds LC Streak-Chested Antpitta Hylopezus perspicillatus The streak-chested antpitta has a pale, spectacled eye-ring and a streaked breast, and like most of its family it is heard calling far more often than it is ever actually seen. Read the guide →
Amphibians LC Streamside Salamander Ambystoma barbouri The streamside salamander broke from its family's usual habit of breeding in still ponds, laying its eggs instead in flowing streams where its larvae hatch already equipped to handle a current. Read the guide →
Amphibians LC Strecker's Chorus Frog Pseudacris streckeri Strecker's chorus frog spends most of the year buried underground, only emerging after rain to call from temporary prairie pools, a stocky, burrowing frog marked by a bold dark stripe across its face. Read the guide →
Birds NT Striated Caracara Phalcoboenus australis The striated caracara, nicknamed Johnny rook by Falkland Islanders, is famous for its extreme curiosity, routinely investigating and stealing items from human camps. Read the guide →
Mammals LC Stripe-Necked Mongoose Herpestes vitticollis The stripe-necked mongoose carries a bold dark stripe running down the side of its neck, one of the larger Asian mongoose species found across the forests of southern India and Sri Lanka. Read the guide →
Fish LC Striped Bass Morone saxatilis The striped bass is the great migratory sport fish of the US Atlantic coast, a silver, seven-striped river-spawning predator whose 1980s collapse and recovery is a fisheries classic. Read the guide →
Amphibians LC Striped Chorus Frog Pseudacris nigrita The striped chorus frog breeds in shallow, temporary coastal-plain pools, and its males call in such dense choruses that individual calls blur into a single continuous buzzing wall of sound. Read the guide →
Reptiles LC Striped Crayfish Snake Regina alleni The striped crayfish snake stays almost entirely underwater in Florida marshes, timing its hunts specifically to catch crayfish just after they molt, when their new shells are still soft. Read the guide →
Mammals LC Striped Dolphin Stenella coeruleoalba The striped dolphin performs some of the highest leaps of any dolphin, launching several metres into the air, a distinctively marked deep-water species named for the dark stripes along its sides. Read the guide →
Mammals NT Striped Hyena Hyaena hyaena The striped hyena is the most widespread hyena, a shy, striped scavenger that raises a long mane along its back to look larger and ranges from North Africa to India. Read the guide →
Birds LC Striped Kingfisher Halcyon chelicuti The striped kingfisher is one of the smaller African savanna kingfishers, marking its territory with a distinctive display flight rather than the loud calls many relatives use. Read the guide →
Fish NT Striped Marlin Kajikia audax The striped marlin has been recorded reaching some of the fastest burst speeds of any fish, its stripes flashing brighter during the coordinated group hunts it launches against schooling prey. Read the guide →
Reptiles LC Striped Mud Turtle Kinosternon baurii The striped mud turtle can seal its shell more completely than most other mud turtles, closing itself away almost entirely thanks to a double-hinged plastron. Read the guide →
Fish LC Striped Mullet Mugil cephalus The striped mullet is famous for leaping clear out of the water for no obvious reason, a behaviour common enough that its exact cause is still debated among researchers who study the species. Read the guide →
Amphibians NT Striped Newt Notophthalmus perstriatus A striped newt is a small red-striped newt of the southeastern US that breeds in seasonal ponds, shelters in gopher tortoise burrows through drought, and is one of the region's rarest amphibians. Read the guide →
Mammals LC Striped Polecat Ictonyx striatus The striped polecat looks like a skunk and defends itself like one, spraying a foul fluid from glands under its tail smellable hundreds of metres away. It is often called the smelliest animal alive. Read the guide →
Mammals LC Striped Possum Dactylopsila trivirgata The striped possum uses a dramatically elongated fourth finger to hook grubs out of tree bark, a skunk-striped rainforest specialist with a famously pungent odor. Read the guide →
Fish LC Striped Shiner Luxilus chrysocephalus A breeding male striped shiner develops a rosy-pink flush and rows of hard bumps across its head, transforming from an unremarkable silver minnow into one of the more colourful fish in its stream. Read the guide →
Mammals LC Striped Skunk Mephitis mephitis The striped skunk sprays an oily, sulfur-based musk it can aim several metres, but its bold black-and-white warning coat means it rarely has to; most predators learn to leave it alone. Read the guide →
Reptiles LC Striped Swamp Snake Liodytes pygaea The striped swamp snake spends nearly all its life within dense aquatic vegetation, a small, secretive predator of southeastern wetlands rarely seen away from the plant mats it depends on for cover. Read the guide →
Reptiles LC Striped Whipsnake Coluber taeniatus The striped whipsnake moves across open ground faster than almost any other North American snake, hunting by day with its head raised and eyes tracking for movement well ahead. Read the guide →
Amphibians LC Stripeless Tree Frog Hyla meridionalis The stripeless tree frog lacks the dark side stripe nearly every other European tree frog carries, a single missing marking that gives it both its common name and easiest identification feature. Read the guide →
Fish CR Sturgeon Acipenseridae A sturgeon is a huge, armour-plated fish little changed in 200 million years, feeling for food along the riverbed with whiskered barbels, and one of the most endangered groups of animals on Earth. Read the guide →
Mammals LC Subantarctic Fur Seal Arctocephalus tropicalis The subantarctic fur seal has a distinctive orange-yellow face and chest contrasting with dark fur, breeding on islands considerably further north than most other fur seal species in the region. Read the guide →
Mammals NT Sucker-footed Bat Myzopoda aurita The sucker-footed bat evolved adhesive pads on its wrists and ankles independently from similar bats half a world away, letting it cling inside a rolled traveler's palm leaf found only on Madagascar. Read the guide →
Mammals LC Sugar Glider Petaurus breviceps The sugar glider is a small nocturnal marsupial that glides up to 50 metres between trees on a membrane stretched wrist to ankle, steering with its tail. Family groups share a single scent. Read the guide →
Mammals VU Sulawesi Babirusa Babyrousa celebensis The Sulawesi babirusa is a Vulnerable wild pig whose upper tusks grow up through its snout and curve back toward its forehead, found only on the Indonesian island of Sulawesi. Read the guide →
Birds LC Sulphur-Crested Cockatoo Cacatua galerita The sulphur-crested cockatoo can live 70 years or more, and in Sydney some populations have learned to flip open garbage bin lids, a skill that has spread bird to bird across entire suburbs. Read the guide →
Mammals CR Sumatran Orangutan Pongo abelii The Sumatran orangutan waits nearly nine years between births, the longest interval of any land mammal, a slow-reproducing ape now Critically Endangered. Read the guide →
Mammals CR Sumatran Striped Rabbit Nesolagus netscheri The Sumatran striped rabbit is one of the rarest and least-studied mammals on Earth, a dark-striped rabbit so elusive it has been photographed in the wild only a handful of times. Read the guide →
Birds LC Summer Tanager Piranga rubra The summer tanager is the only entirely red bird in North America, specializing in catching bees and wasps and rubbing off their stingers before eating. Read the guide →
Mammals VU Sun Bear Helarctos malayanus The sun bear is the smallest bear on Earth, with a 25-centimetre tongue for raiding beehives and a chest patch shaped like a rising sun. Learn how this tree-climbing forest bear lives. Read the guide →
Birds EN Sun Conure Aratinga solstitialis The sun conure blazes with solid golden-orange plumage, yet despite being one of the most recognisable pet parrots in the world its wild population has collapsed to Endangered levels. Read the guide →
Reptiles LC Sunbeam Snake Xenopeltis unicolor The sunbeam snake is a burrowing snake whose smooth, glossy scales scatter light into a shifting rainbow sheen, an iridescent effect on a plain brown body that gives the species its name. Read the guide →
Birds LC Sunbird Nectariniidae A sunbird is a small, iridescent Old World nectar-feeder that fills much the same ecological role as a hummingbird, though it perches to drink from flowers rather than hovering in mid-air. Read the guide →
Birds LC Sunbittern Eurypyga helias The sunbittern is a slender, cryptically patterned wading bird that, when threatened, snaps its wings wide to reveal two huge chestnut-and-gold eyespots, becoming what looks like a much larger face. Read the guide →
Fish LC Sunbleak Leucaspius delineatus The sunbleak is a tiny, silvery European shoaling fish with an upturned mouth whose male guards a spiral string of eggs wrapped around a reed stem, and which has become an invader in Britain. Read the guide →
Mammals VU Sunda Clouded Leopard Neofelis diardi The Sunda clouded leopard was recognized as its own species only in 2006, found exclusively on the islands of Borneo and Sumatra, where it hunts as the largest predator in its forest. Read the guide →
Invertebrates CR Sunflower Sea Star Pycnopodia helianthoides The sunflower sea star is one of the largest and fastest sea stars, a 24-armed kelp-forest predator that a marine disease nearly wiped out after 2013, triggering urchin outbreaks and kelp collapse. Read the guide →
Reptiles VU Sungazer Smaug giganteus The sungazer is a spiny, heavily armoured lizard of South African grassland. Unlike its rock-dwelling relatives it digs its own burrows and basks at the entrance, head tilted as if gazing at the sun. Read the guide →
Birds LC Sungrebe Heliornis fulica The sungrebe is a secretive Central American waterbird with a trick found in no other bird — the male carries his tiny chicks in a pair of skin pouches under his wings, even in flight. Read the guide →
Mammals LC Suni Neotragus moschatus The suni is one of the smallest antelope in the world, a secretive forest-floor dweller small enough to slip through gaps in dense undergrowth that would stop most other mammals. Read the guide →
Birds LC Superb Bird-of-paradise Lophorina The male superb bird-of-paradise snaps up a black cape and blue breast shield into an oval that hops around the female like a smiling face. Its black plumage absorbs 99.95% of light. Read the guide →
Birds LC Superb Fairywren Malurus cyaneus The superb fairywren is a tiny Australian bird with a cocked tail and, on breeding males, a brilliant blue crown. It is socially monogamous but among the least faithful birds ever studied. Read the guide →
Birds LC Superb Lyrebird Menura novaehollandiae The superb lyrebird is the finest vocal mimic on Earth — it copies other birds, koalas, camera shutters, chainsaws, and car alarms, weaving them into a display song on a forest-floor mound. Read the guide →
Fish LC Surgeonfish Acanthuridae A surgeonfish carries a hidden, razor-sharp blade folded against each side of its tail base, a weapon it flicks out only when threatened, giving the whole family its name. Read the guide →
Amphibians LC Surinam Horned Frog Ceratophrys cornuta The Surinam horned frog is almost all mouth, a squat ambush predator that buries itself and swallows anything that walks past, including frogs, mice, and small snakes nearly its own size. Read the guide →
Amphibians LC Surinam Toad Pipa pipa The Surinam toad is a flat, leaf-shaped aquatic frog whose babies erupt from pits in the mother's back. It has no tongue or teeth and feels for prey with star-tipped fingers in murky water. Read the guide →
Fish LC Suwannee Bass Micropterus notius The Suwannee bass is found naturally in only two river systems, both in northern Florida and southern Georgia, making it one of the most geographically restricted black bass species in North America. Read the guide →
Birds LC Swainson's Hawk Buteo swainsoni Swainson's hawk migrates farther than almost any other North American raptor, flying thousands of miles to Argentina's pampas and switching its diet mostly to grasshoppers along the way. Read the guide →
Birds LC Swainson's Thrush Catharus ustulatus Swainson's thrush sings an ethereal, upward-spiraling song, the mirror opposite of the veery's downward spiral, and migrates almost entirely at night, calling overhead in a thin, distinctive peep. Read the guide →
Birds LC Swallow Hirundinidae A swallow is a slender, fork-tailed bird that catches insects on the wing over fields and water, builds a cup of mud, and makes some of the longest migrations of any small land bird. Read the guide →
Birds LC Swallow Tanager Tersina viridis The swallow tanager catches insects in mid-flight like a swallow, an unusual hunting style for a tanager, and nests in burrows rather than open cups. Read the guide →
Birds LC Swallow-tailed Gull Creagrus furcatus The swallow-tailed gull is the only truly nocturnal gull in the world, hunting squid at night with unusually large eyes and returning by day to the Galapagos Islands it calls home almost exclusively. Read the guide →
Birds LC Swallow-Tailed Kite Elanoides forficatus The swallow-tailed kite catches, eats, and even drinks entirely on the wing, its deeply forked tail allowing acrobatic mid-air turns that let it snatch prey without ever needing to land. Read the guide →
Fish LC Swamp Darter Etheostoma fusiforme The swamp darter is one of the very few darter species that thrives in still, weedy, low-oxygen swamp water, a habitat almost every other member of its fast-water-loving family avoids entirely. Read the guide →
Birds LC Swamp Sparrow Melospiza georgiana The swamp sparrow forages by wading directly into shallow marsh water, sometimes submerging its head entirely to snatch aquatic insects most other sparrows would never attempt to reach. Read the guide →
Mammals LC Swamp Wallaby Wallabia bicolor The swamp wallaby is the only species in its genus and can carry an embryo in reserve even while still nursing an older joey, thanks to overlapping pregnancies. Read the guide →
Birds NE Swan Cygnus A swan is the largest and heaviest of the waterfowl, a long-necked grazer of underwater plants that pairs for years, defends its family fiercely, and in some species barely gets airborne at all. Read the guide →
Invertebrates LC Swan Mussel Anodonta cygnea The swan mussel is a large, thin-shelled freshwater mussel of European lakes and slow rivers that ploughs a trail through the mud, filters the water, and sends its larvae to hitch a ride on fish. Read the guide →
Invertebrates LC Sweat Bee Halictidae The sweat bee is drawn to human perspiration for its salt content, landing directly on skin to drink it, a habit unusual enough among bees to give the whole family its common name. Read the guide →
Fish LC Swell Shark Cephaloscyllium ventriosum The swell shark is a small Pacific catshark that gulps water to double its size and jam itself into a rock crevice. Its skin glows green under blue light in a pattern only other swell sharks can see. Read the guide →
Birds NE Swift Apodidae A swift is a bird so committed to the air that some species stay aloft for up to ten months without landing, doing everything on the wing, and it cannot perch or take off from flat ground. Read the guide →
Mammals LC Swift Fox Vulpes velox The swift fox nearly vanished from the North American plains in the 20th century, a small, fast grassland fox caught in poisoning aimed at wolves and coyotes, now recovering through reintroduction. Read the guide →
Birds LC Swiftlet Aerodramus A swiftlet is a small cave-nesting bird that navigates total darkness using echolocation like a bat, and its saliva-built nest is the key ingredient in bird's nest soup. Read the guide →
Birds LC Sword-billed Hummingbird Ensifera ensifera The sword-billed hummingbird is the only bird whose bill is longer than the rest of its body. It reaches nectar no other hummingbird can, but must perch with its head tilted almost straight up. Read the guide →
Fish LC Swordfish Xiphias gladius The swordfish uses its long flat bill to slash through schools of fish, warms its eyes and brain with a special organ so it can hunt in the cold deep, and is one of the fastest fish in the sea. Read the guide →
Fish LC Swordtail Xiphophorus hellerii A swordtail is a hardy Central American livebearer named for the blade extending from the male's tail, a classic beginner aquarium fish and a lab model for the genetics of colour and melanoma. Read the guide →
Invertebrates LC Sydney Funnel-Web Spider Atrax robustus The Sydney funnel-web is often called the world's most dangerous spider — its venom can kill a person in under an hour — but no death has been recorded since an antivenom arrived in 1981. Read the guide →
Mammals VU Syrian Hamster Mesocricetus auratus The Syrian hamster is the familiar pet hamster, descended almost entirely from a single wild litter caught in Syria in 1930, while wild populations have become scarce. Read the guide →
Birds LC Syrian Woodpecker Dryobates syriacus The Syrian woodpecker looks almost identical to the great spotted woodpecker but shows a far greater tolerance for orchards, parks, and gardens, helping it steadily expand its range. Read the guide →
Amphibians CR Table Mountain Ghost Frog Heleophryne rosei The Table Mountain ghost frog lives only in a few fast streams above Cape Town. It climbs wet vertical rock on sticky toes, and its tadpoles grip boulders in the torrent with a sucker mouth. Read the guide →
Amphibians NE Tadpole Anura A tadpole is the larva of a frog or toad, a legless, gilled swimmer that grazes on algae and then rebuilds its entire body, growing legs, absorbing its tail, and switching to breathing air. Read the guide →
Fish LC Tadpole Madtom Noturus gyrinus The tadpole madtom is named for its stout, rounded body shape that resembles a tadpole rather than a typical catfish, and it is the most widely distributed madtom species in North America. Read the guide →
Amphibians LC Tailed Frog Ascaphus truei The tailed frog is one of the most primitive frogs alive and the only North American frog with internal fertilisation, and its tadpoles grip rocks in freezing torrents with a sucker mouth. Read the guide →
Invertebrates NE Tailless Whip Scorpion Amblypygi The tailless whip scorpion is neither a spider nor a scorpion and has no venom at all. It feels through the dark with one pair of legs modified into whip-like feelers many times its body length. Read the guide →
Reptiles LC Taipan Oxyuranus A taipan is a large, fast Australian elapid, and the inland taipan has the most toxic venom of any snake on Earth, while the coastal taipan is Australia's most dangerous snake in practice. Read the guide →
Birds EN Takahe Porphyrio hochstetteri A stocky flightless rail from New Zealand's alpine tussock grassland, the takahe was declared extinct, rediscovered in 1948, and slowly rebuilt from a few hundred birds by decades of protection. Read the guide →
Mammals VU Takin Budorcas taxicolor The takin is Bhutan's national animal, a bulky, golden-coated goat-antelope with a large arched nose that helps warm frigid mountain air before it reaches the lungs. Read the guide →
Fish LC Tambaqui Colossoma macropomum The tambaqui is one of the largest scaled freshwater fish in South America, using flat, molar-like teeth to crack open nuts and seeds that fall into flooded Amazon forest. Read the guide →
Birds LC Tanager Thraupidae A tanager belongs to one of the largest, most colourful songbird families in the Americas, ranging from vivid scarlet and blue species to the understated relatives that make up much of the family. Read the guide →
Fish LC Tangerine Darter Percina aurantiaca The tangerine darter is among the largest darters in North America, and a breeding male flushes a vivid orange along its lower body bright enough to be spotted from well above the water's surface. Read the guide →
Birds LC Tapaculo Rhinocryptidae A tapaculo is a small South American songbird that would rather run through dense undergrowth than fly, so shy and skulking that most species are far easier to hear than to see. Read the guide →
Mammals CR Tapanuli Orangutan Pongo tapanuliensis The Tapanuli orangutan was described as a new species in 2017, the rarest great ape, with fewer than a thousand animals in a small block of forest on the Indonesian island of Sumatra. Read the guide →
Invertebrates NE Tapeworm Cestoda The tapeworm has no mouth and no gut at all, absorbing already-digested food directly through its skin while living entirely inside another animal's intestine. Read the guide →
Amphibians VU Tarahumara Frog Lithobates tarahumarae The Tarahumara frog vanished from the United States by the 1980s, only to be brought back through a deliberate reintroduction program using frogs collected from surviving populations in Mexico. Read the guide →
Invertebrates LC Tarantula Hawk Pepsis grossa The tarantula hawk is a large wasp that hunts tarantulas, paralysing a spider many times its size and burying it alive for a single grub. Its sting is rated among the most painful of any insect. Read the guide →
Invertebrates NE Tardigrade Ramazzottius varieornatus The tardigrade, or water bear, is a half-millimetre eight-legged animal that survives boiling, freezing, vacuum, radiation, and years without water by drying into a near-lifeless tun and waiting. Read the guide →
Fish VU Tarpon Megalops atlanticus A tarpon is a huge, armour-scaled silver gamefish of warm coasts that gulps air to survive stagnant water, leaps clear when hooked, and is among the most prized catch-and-release sport fish. Read the guide →
Mammals NT Tarsier Tarsius and related genera A tarsier's eye is bigger than its brain and cannot move, so it turns its head almost 180 degrees like an owl. It is the only fully carnivorous primate, taking insects with leaps of several metres. Read the guide →
Mammals EN Tasmanian Devil Sarcophilus harrisii The Tasmanian devil is the world's largest carnivorous marsupial — a bone-crushing scavenger fighting a contagious cancer that has killed most of the wild population. Learn how it's being saved. Read the guide →
Birds LC Tasmanian Nativehen Tribonyx mortierii The Tasmanian nativehen is a large, flightless rail found only on the island of Tasmania, a fast runner able to reach surprising speeds across open grassland despite having given up flight entirely. Read the guide →
Mammals LC Tasmanian Pademelon Thylogale billardierii The Tasmanian pademelon vanished from mainland Australia over a century ago but still thrives as a common, shy forest browser across Tasmania today. Read the guide →
Fish LC Tasselled Wobbegong Eucrossorhinus dasypogon The tasselled wobbegong is a flat, carpet-patterned reef shark fringed with skin flaps that make it vanish against coral. It lies still and ambushes fish, sometimes luring them with its own tail. Read the guide →
Birds LC Tataupa Tinamou Crypturellus tataupa The tataupa tinamou is a small, secretive ground bird of South American woodland edges, more often heard through its distinctive whistled call than seen among the dense undergrowth it favours. Read the guide →
Birds LC Tawny Frogmouth Podargus strigoides The tawny frogmouth is an Australian night bird often mistaken for an owl. By day it freezes upright on a branch, beak skyward, becoming a broken stub of wood. Read the guide →
Invertebrates LC Tawny Mining Bee Andrena fulva The tawny mining bee is a foxy-red, furry solitary bee whose females dig nest burrows in lawns and bare soil, leaving small volcano-shaped mounds, and flies in a brief spring season. Read the guide →
Birds LC Tawny-throated Dotterel Oreopholus ruficollis The tawny-throated dotterel breeds across open Patagonian grassland far from any coastline, migrating thousands of kilometres between breeding and non-breeding range each year. Read the guide →
Mammals LC Tayra Eira barbara The tayra is a large, agile weasel of Latin American forests. It eats a lot of fruit, and it has been filmed picking unripe plantains, hiding them, and coming back days later to eat them ripe. Read the guide →
Reptiles LC Tegu Salvator and Tupinambis A tegu is a large, intelligent, dog-tempered South American lizard that eats almost anything, warms its body above the night air while breeding, and is now an invasive pest in the southeastern US. Read the guide →
Amphibians EN Tehachapi Slender Salamander Batrachoseps stebbinsi The Tehachapi slender salamander survives in just a handful of isolated canyon sites, a range so small and fragmented that a single local disturbance could threaten an entire population at once. Read the guide →
Fish LC Telescope Fish Gigantura chuni The telescope fish has tubular, upward-pointing eyes built to gather every last scrap of light in the deep sea, paired with a stomach that can stretch around prey nearly as large as itself. Read the guide →
Fish LC Telescope Shiner Notropis telescopus The telescope shiner has unusually large, forward-directed eyes that give the species its common name, an adaptation thought to help it track fast-drifting insect prey in clear, flowing water. Read the guide →
Amphibians LC Tellico Salamander Plethodon aureolus The Tellico salamander breathes entirely through its skin and lays eggs on land with no aquatic larval stage, confined to a small pocket of the southern Appalachians. Read the guide →
Fish LC Tench Tinca tinca The tench is a thick, olive-gold European carp relative coated in heavy slime, a bottom feeder of muddy still waters that folklore once claimed could heal other fish that rubbed against it. Read the guide →
Amphibians VU Tennessee Cave Salamander Gyrinophilus palleucus The Tennessee cave salamander is a pale, big-gilled amphibian that spends its whole life as a larva in the black streams of a few hundred caves, never leaving the water and never growing up. Read the guide →
Mammals LC Tent-making Bat Uroderma bilobatum The tent-making bat bites precise lines along a large leaf's veins until it collapses into a tent shape, building a private shelter that keeps rain, sun, and predators at bay. Read the guide →
Reptiles LC Tentacled Snake Erpeton tentaculatum The tentacled snake is a fully aquatic Southeast Asian snake with two feelers on its snout that sense nearby fish. It hunts by twitching its body to make a fish flee straight into its jaws. Read the guide →
Invertebrates LC Termite Infraorder Isoptera Termites are social cockroaches, not ants; between them they recycle much of the world's dead wood and grass, build the tallest structures any animal makes, and in some species farm fungus. Read the guide →
Fish LC Tessellated Darter Etheostoma olmstedi The tessellated darter carries a mottled pattern of small dark blotches resembling tiny tiles, and it tolerates a wider range of water conditions than many of its pickier darter relatives. Read the guide →
Fish LC Tetra Characidae A tetra is one of thousands of small, schooling freshwater fish in one enormous family, ranging from the aquarium-famous neon tetra to a considerably less peaceful relative, the piranha. Read the guide →
Reptiles LC Texas Alligator Lizard Gerrhonotus infernalis The Texas alligator lizard is the largest alligator lizard species in North America, living in rocky Hill Country terrain and giving birth to live young. Read the guide →
Reptiles LC Texas Banded Gecko Coleonyx brevis The Texas banded gecko is one of the few geckos with movable eyelids, a small nocturnal ground-dweller that drops its tail to escape and never climbs the way most geckos do. Read the guide →
Amphibians VU Texas Blind Salamander Eurycea rathbuni The Texas blind salamander lives its whole life in flooded limestone caves under one Texas city, with no eyes, no pigment, and blood-red external gills. It exists nowhere else on Earth. Read the guide →
Reptiles LC Texas Blind Snake Rena dulcis The Texas blind snake spends nearly its entire life underground raiding ant and termite nests, and screech owls have been documented bringing live ones home as pest control. Read the guide →
Fish LC Texas Cichlid Herichthys cyanoguttatus The Texas cichlid is the only cichlid species native to the United States, tolerating water temperatures far colder than almost any other member of a family famous for needing warmth. Read the guide →
Reptiles LC Texas Cooter Pseudemys texana The Texas cooter is restricted almost entirely to river systems within the state its name references, a basking turtle whose narrow range makes it one of the more geographically specific US reptiles. Read the guide →
Reptiles LC Texas Horned Lizard Phrynosoma cornutum The Texas horned lizard is a flat, spiky, ant-eating desert lizard that, when a coyote or fox grabs it, can squirt a jet of foul-tasting blood from a sinus in the corner of its own eye. Read the guide →
Reptiles LC Texas Map Turtle Graptemys versa The Texas map turtle is found only within a single Texas river system, and females grow a noticeably wider, crushing jaw than males, letting them tackle snails and mussels males can't manage. Read the guide →
Amphibians NT Texas Salamander Eurycea neotenes The Texas salamander never grows up in the usual sense, keeping its larval gills for life within the same Edwards Aquifer springs that support several of its more famous cave-dwelling relatives. Read the guide →
Reptiles LC Texas Spiny Lizard Sceloporus olivaceus The Texas spiny lizard spirals around a tree trunk to keep the wood between itself and an approaching threat, staying just out of sight without ever fully committing to fleeing. Read the guide →
Reptiles LC Texas Spotted Whiptail Aspidoscelis gularis The Texas spotted whiptail is one of the most common lizards across its range, a fast, nervous forager that rarely stays still long enough for a predator, or a curious observer, to get a close look. Read the guide →
Amphibians LC Texas Toad Anaxyrus speciosus The Texas toad emerges by the thousands after a single heavy summer downpour, an explosive breeder whose entire reproductive year can hinge on just a handful of rain events across its arid range. Read the guide →
Reptiles NT Texas Tortoise Gopherus berlandieri The Texas tortoise digs only a shallow scrape rather than a deep burrow, the smallest and least excavation-minded of North America's gopher tortoises. Read the guide →
Birds LC Thick-Knee Burhinidae The thick-knee freezes flat against open ground the instant it senses danger, its cryptic plumage and huge yellow eyes making a bird standing in plain sight remarkably easy to walk right past. Read the guide →
Fish LC Thicklip Grey Mullet Chelon labrosus The thicklip grey mullet is a heavy-lipped, silver-grey grazer of European harbours, estuaries, and shores that scrapes algae and mud from stones and piers and enters brackish water. Read the guide →
Mammals LC Thirteen-lined Ground Squirrel Ictidomys tridecemlineatus The thirteen-lined ground squirrel hibernates with its body temperature dropping to around freezing, a striped Great Plains burrower studied for how it survives the winter. Read the guide →
Mammals NT Thomson's Gazelle Eudorcas thomsonii Thomson's gazelle bounces through a stiff-legged jump just like the springbok, a small, fast antelope whose herds form part of the Serengeti's annual migration. Read the guide →
Invertebrates NE Thorn Bug Umbonia The thorn bug carries an oversized, thorn-shaped shield on its back, and clusters of them lining a plant stem can pass convincingly for a row of sharp thorns. Read the guide →
Birds LC Thorn-tailed Rayadito Aphrastura spinicauda The thorn-tailed rayadito is a small, active songbird with spiny tail feathers used for balance, breeding further south than almost any other passerine bird in the Americas. Read the guide →
Fish NT Thornback Ray Raja clavata The thornback ray is a diamond-shaped bottom fish of north-eastern Atlantic shelf seas whose back and tail are studded with prickly thorns, and whose egg cases wash up on beaches as mermaid's purses. Read the guide →
Reptiles LC Thorny Devil Moloch horridus The thorny devil is a spiky Australian desert lizard that drinks with its skin — grooves between its scales wick water from damp sand and dew straight to its mouth by capillary action. Read the guide →
Fish LC Threadfin Shad Dorosoma petenense The threadfin shad dies off in mass numbers whenever water temperatures drop sharply, a cold-sensitive forage fish deliberately stocked across reservoirs nationwide despite that same fragility. Read the guide →
Amphibians LC Three-Lined Salamander Eurycea guttolineata The three-lined salamander has a notably long tail making up well over half its total length, an exaggerated proportion that helps it wriggle rapidly through dense leaf litter and grass. Read the guide →
Fish LC Three-spined Stickleback Gasterosteus aculeatus The three-spined stickleback is a tiny armoured fish of northern waters whose courting male turns red-throated, builds a glued tunnel nest, and is a leading model for studying evolution. Read the guide →
Fish LC Three-spot Damselfish Dascyllus trimaculatus The three-spot damselfish carries a bold white spot on its forehead and one on each side as a juvenile, often sheltering safely among the stinging tentacles of a sea anemone. Read the guide →
Fish LC Three-Spot Gourami Trichopodus trichopterus The three-spot gourami is one of the most widely kept aquarium fish in the world, its two body spots and eye together forming the "three spots" that give the species its name. Read the guide →
Mammals LC Three-striped Night Monkey Aotus trivirgatus The three-striped night monkey is one of the few truly nocturnal monkeys, with huge eyes and three dark stripes on its face, and the male carries the baby most of the time. Read the guide →
Amphibians LC Three-toed Amphiuma Amphiuma tridactylum The three-toed amphiuma is the largest species of amphiuma, an eel-like salamander with legs so tiny they are barely functional, delivering a surprisingly painful bite despite its harmless look. Read the guide →
Birds LC Three-toed Woodpecker Picoides tridactylus The three-toed woodpecker breaks the standard bird body plan with only three toes instead of four, an adaptation that helps it grip while stripping bark for beetle larvae. Read the guide →
Birds VU Three-wattled Bellbird Procnias tricarunculatus The three-wattled bellbird produces one of the loudest calls of any bird on Earth, males displaying three long fleshy wattles that dangle from the base of the bill. Read the guide →
Fish LC Threespine Stickleback Gasterosteus aculeatus The threespine stickleback is a key example of evolution in action, with separate freshwater populations repeatedly evolving the same reduced armour and spines after colonising lakes from the sea. Read the guide →
Invertebrates LC Thrips Thysanoptera A thrips is a tiny, slender insect with fringed wings that pierces plant cells to feed, damages crops directly and by spreading plant viruses, and turns up on skin in warm, thundery weather. Read the guide →
Birds LC Thrush Turdidae A thrush is a family of plump, often spotted songbirds that includes the robin and the bluebird, and the song thrush famously smashes snail shells on a favourite stone anvil. Read the guide →
Mammals EX Thylacine Thylacinus cynocephalus The thylacine was a dog-shaped marsupial predator with a striped back and a pouch in both sexes. Blamed for sheep losses and hunted out, it was declared extinct after the last one died in 1936. Read the guide →
Invertebrates NE Tick Ixodida A tick is an eight-legged, blood-feeding arachnid that waits on vegetation for a passing animal and clings on for days, spreading more diseases to people and livestock than anything but the mosquito. Read the guide →
Mammals EN Tiger Panthera tigris The tiger is the largest cat on Earth and a solitary ambush hunter. Learn how it stalks prey, why every tiger's stripes are unique, and why fewer than 5,600 remain wild. Read the guide →
Invertebrates LC Tiger Beetle Cicindelinae The tiger beetle sprints so fast relative to its size that some species must pause mid-chase, briefly unable to gather enough light to actually see where they're going. Read the guide →
Reptiles LC Tiger Rattlesnake Crotalus tigris The tiger rattlesnake carries some of the most toxic venom of any rattlesnake by weight, despite a notably small head and a generally mild-mannered temperament. Read the guide →
Amphibians LC Tiger Salamander Ambystoma tigrinum The tiger salamander is one of the largest land salamanders in the world — a burrowing predator that spends most of its life underground and can, in some populations, skip metamorphosis for life. Read the guide →
Fish NT Tiger Shark Galeocerdo cuvier The tiger shark eats almost anything — turtles, seabirds, dolphins, other sharks, and the occasional car tyre. Learn how its serrated teeth and roaming lifestyle make it a key ocean predator. Read the guide →
Reptiles LC Tiger Snake Notechis scutatus The tiger snake is a highly venomous Australian snake of southern wetlands, often banded like a tiger, that flattens its neck when threatened and gives birth to live young. Read the guide →
Amphibians LC Tiger-legged Monkey Frog Phyllomedusa tomopterna The tiger-legged monkey frog walks branches hand over hand, gripping with opposable fingers like a tiny primate. It wipes a waxy secretion over its skin to survive open sun and dry air. Read the guide →
Fish LC Tigerfish Hydrocynus A tigerfish is a fast, striped, dagger-toothed African river predator, and the goliath tigerfish is feared as the African piranha and has been filmed leaping to catch swallows in flight. Read the guide →
Fish LC Tilapia Oreochromis and relatives A tilapia is a hardy African cichlid that has become one of the most farmed and eaten fish in the world, prized for fast growth on a plant diet and blamed as an invasive pest outside Africa. Read the guide →
Fish LC Tilefish Lopholatilus chamaeleonticeps A tilefish digs and maintains an elaborate burrow in the sea floor, sometimes piling up debris into a mound at the entrance, one of the more architecturally ambitious homes built by any fish. Read the guide →
Reptiles LC Timber Rattlesnake Crotalus horridus The timber rattlesnake is a large, mild-mannered pit viper of eastern US forests and the snake of the Gadsden flag, now vanishing in the north where whole populations share one ancient winter den. Read the guide →
Birds LC Tinamou Tinamidae A tinamou looks like an ordinary plump game bird but carries a lineage closer to ratites than to any pheasant, and in most species the male alone incubates eggs from several females. Read the guide →
Invertebrates NE Titan Beetle Titanus giganteus The titan beetle is the largest beetle by body length — up to 17 cm — and its adults never feed. They live a few weeks to mate, their jaws can snap a pencil, and their grubs have never been found. Read the guide →
Fish LC Titan Triggerfish Balistoides viridescens The titan triggerfish is the largest triggerfish and the reef fish most likely to charge a diver, guarding a huge nest pit dug in the sand. It crunches sea urchins with beak-like teeth. Read the guide →
Mammals LC Titi Monkey Callicebus The titi monkey forms lifelong monogamous pairs that sit together with their long tails intertwined, reinforcing a bond defended daily with loud, duetting territorial calls. Read the guide →
Amphibians CR Titicaca Water Frog Telmatobius culeus The Titicaca water frog lives its whole life underwater in a high Andean lake, breathing through baggy folds of skin. It is Critically Endangered, hit by pollution and a demand for frog "juice". Read the guide →
Amphibians NE Toad Bufonidae A toad is a frog with dry, warty skin and short legs that walks rather than leaps, carries a pair of poison glands behind the eyes, and returns each spring to the pond where it was born. Read the guide →
Fish LC Toadfish Batrachoididae A toadfish is a squat, lumpy bottom-dweller that hums and grunts loud enough to keep boat dwellers awake, drumming muscles against its swim bladder faster than any other vertebrate muscle contracts. Read the guide →
Invertebrates LC Tobacco Hornworm Manduca sexta The tobacco hornworm is a favorite lab research subject worldwide, and its natural predator, a tiny braconid wasp, often studs the caterpillar's back with white cocoons before it finishes growing. Read the guide →
Birds LC Toco Toucan Ramphastos toco The toco toucan has the largest bill relative to body size of any bird — a lightweight, honeycombed structure it uses as a fruit-picker, a weapon reach-extender, and a radiator that dumps body heat. Read the guide →
Birds LC Tody Todus A tody is a tiny, bright green Caribbean bird found nowhere else on Earth, catching insects with a sudden sideways lunge from a perch after a hunting posture that looks almost comically alert. Read the guide →
Reptiles LC Tokay Gecko Gekko gecko The tokay gecko is a large, loud, blue-and-orange-spotted lizard whose barking "to-kay" call gave it its name. Read the guide →
Amphibians LC Tomato Frog Dyscophus antongilii The tomato frog is a round, bright-red Madagascan frog that puffs up like a balloon when threatened and oozes a sticky white glue from its skin that gums up a predator's mouth. Read the guide →
Invertebrates LC Tomato Hornworm Manduca quinquemaculata The tomato hornworm can strip a plant of its leaves within days, and a caterpillar covered in small white cocoons has already been fatally parasitized by a wasp from the inside out. Read the guide →
Fish LC Tompot Blenny Parablennius gattorugine The tompot blenny is a bold, banded, branch-tentacled little fish of north-eastern Atlantic rocky reefs that sits at the mouth of its crevice, watching the world, with the male guarding the eggs. Read the guide →
Invertebrates LC Tongue Worm Pentastomida A tongue worm is a parasite living inside the lungs or nasal passages of a reptile, and despite its wormlike body it is now understood to be a bizarre, highly modified relative of crustaceans. Read the guide →
Invertebrates NE Tongue-eating Louse Cymothoa exigua The tongue-eating louse is a parasitic isopod that enters a fish through the gills, severs the tongue's blood supply until it withers away, then takes the tongue's place in the mouth. Read the guide →
Mammals CR Tonkin Snub-nosed Monkey Rhinopithecus avunculus The Tonkin snub-nosed monkey is a Critically Endangered black-and-white monkey with an upturned nose, found only in a few small patches of limestone forest in northern Vietnam. Read the guide →
Fish NT Toothfish Dissostichus The toothfish is a slow-growing, long-lived Antarctic predator marketed under the name Chilean sea bass, and its story includes one of the most severe illegal fishing crises in modern ocean history. Read the guide →
Fish CR Tope Galeorhinus galeus The tope is a slender, long-snouted, grey houndshark that migrates in schools along coasts, bears live young, and has been fished almost to extinction in places for its liver oil and meat. Read the guide →
Mammals LC Topi Damaliscus lunatus The topi climbs onto termite mounds to scan the horizon for predators, a fast, purplish-sheened African antelope that uses these natural watchtowers to keep an eye on danger long before it arrives. Read the guide →
Fish LC Topmouth Gudgeon Pseudorasbora parva The topmouth gudgeon is a tiny, hardy East Asian carp relative that was accidentally introduced to Europe in the 1960s and is now a widespread invader that carries a parasite harmful to native fish. Read the guide →
Birds LC Torrent Duck Merganetta armata The torrent duck lives permanently on fast-flowing Andean mountain rivers, diving and swimming against powerful currents that would sweep away almost any other waterfowl species. Read the guide →
Amphibians LC Torrent Frog Amolops and relatives A torrent frog is any of several unrelated frogs adapted to fast mountain streams, with big sticky toe discs and, in some, a habit of waving a leg to signal because the rushing water drowns out calls. Read the guide →
Amphibians NT Torrent Salamander Rhyacotriton A torrent salamander is a tiny Pacific Northwest amphibian needing some of the coldest, cleanest, best-oxygenated water of any salamander, making it a living gauge of old-growth stream health. Read the guide →
Fish LC Torrent Sculpin Cottus rhotheus The torrent sculpin thrives in the fast, turbulent riffle water its name suggests, holding its position on the streambed with a body built to sink and stay put rather than fight the current. Read the guide →
Reptiles NE Tortoise Testudinidae A tortoise is a land-living turtle with a high domed shell and stumpy elephant-like legs, among the longest-lived of all animals, with several individuals reliably documented past 150 years. Read the guide →
Birds LC Toucan Ramphastidae A toucan is a Central and South American forest bird whose huge, light, colourful bill reaches fruit, raids nests, and sheds body heat, and it nests in tree holes it cannot dig itself. Read the guide →
Birds NT Toucan Barbet Semnornis ramphastinus The toucan barbet sits right at the evolutionary crossroads between barbets and toucans, a colourful Andean cloud forest bird whose features blend both groups into a single striking package. Read the guide →
Mammals LC Townsend's Big-Eared Bat Corynorhinus townsendii Townsend's big-eared bat carries ears nearly as long as its body, which it curls up like rams' horns at rest, and abandons roosts readily when disturbed. Read the guide →
Fish LC Trahira Hoplias malabaricus The trahira is an aggressive ambush predator nicknamed the wolf fish, able to breathe air and survive in oxygen-poor South American rivers and swamps. Read the guide →
Reptiles LC Trans-Pecos Rat Snake Bogertophis subocularis The Trans-Pecos rat snake carries a distinctive H-shaped pattern down its back and large eyes suited to hunting rodents after dark across rugged Chihuahuan Desert canyons. Read the guide →
Invertebrates NE Trap-jaw Ant Odontomachus bauri The trap-jaw ant holds its jaws locked open at 180 degrees and snaps them shut in about a tenth of a millisecond, one of the fastest movements known, used to catch prey and fling itself from danger. Read the guide →
Invertebrates NE Trapdoor Spider Ctenizidae and related families The trapdoor spider builds a silk-lined burrow topped with a hinged, camouflaged lid it holds shut from below, waiting for the vibration of prey. One was tracked in the same burrow for 43 years. Read the guide →
Invertebrates LC Tree Bumblebee Bombus hypnorum The tree bumblebee is a ginger-and-black bumblebee with a white tail that nests above ground in bird boxes and roof spaces, and that colonised Britain from Europe in the early twenty-first century. Read the guide →
Amphibians NE Tree Frog Hylidae A tree frog is any of the small climbing frogs that grip smooth leaves with sticky toe pads, most green for camouflage, and some able to flash bright colours to startle a predator. Read the guide →
Mammals LC Tree Hyrax Dendrohyrax The tree hyrax is a small, nocturnal African forest mammal, distantly related to elephants, best known for the loud, eerie screaming calls that carry through the night. Read the guide →
Reptiles LC Tree Lizard Urosaurus ornatus The tree lizard flashes a colorful throat fan whose exact pattern varies from one desert population to the next, turning territorial display into a kind of regional dialect. Read the guide →
Mammals EN Tree Pangolin Phataginus tricuspis The tree pangolin spends nearly its entire life in the forest canopy, using a strongly prehensile tail to grip branches while climbing in search of ants and termites. Read the guide →
Birds LC Tree Swallow Tachycineta bicolor The tree swallow switches to eating berries when cold snaps wipe out flying insects, a flexibility that lets it migrate farther north than most other aerial insect-hunting birds dare to. Read the guide →
Amphibians LC Tree-hole Frog Metaphrynella sundana The tree-hole frog is a tiny Bornean rainforest frog that tunes its own mating call in real time to match the natural resonant frequency of the water-filled tree cavity it is calling from. Read the guide →
Birds LC Treecreeper Certhia A treecreeper spirals up a tree trunk from the base, probing bark crevices for insects with a thin, downward-curved bill, then flies to the base of the next tree to start again. Read the guide →
Invertebrates NE Treehopper Membracidae The treehopper carries an oversized, oddly shaped pronotum that can mimic a thorn, an ant, or a bird dropping, disguising a soft-bodied sap-feeder in plain sight. Read the guide →
Birds LC Treepie Dendrocitta spp. The treepie moves through forest canopy in noisy, cooperative groups, an intelligent, long-tailed corvid that scavenges alongside larger predators and readily raids other birds' nests. Read the guide →
Birds LC Tricolored Heron Egretta tricolor The tricolored heron chases its prey rather than waiting for it, darting through shallow water in a burst of energy unlike the patient hunting style typical of most other herons. Read the guide →
Fish NE Triggerfish Balistidae A triggerfish is a deep-bodied reef fish that locks its front dorsal spine upright with a second, trigger-like spine, and some big species defend their sea-floor nests by charging and biting divers. Read the guide →
Invertebrates EX Trilobite Trilobita Trilobites were a hugely diverse group of hard-shelled marine arthropods that thrived for over 250 million years and left behind some of the most complete and abundant fossils of any ancient animal. Read the guide →
Invertebrates NE Trilobite Beetle Platerodrilus The female trilobite beetle never grows up, keeping a flat, armour-plated, grub-like body up to 8 cm long that looks like an extinct trilobite. The tiny winged male looks nothing like her. Read the guide →
Invertebrates NE Triops Triops A triops, or tadpole shrimp, is a shield-backed crustacean of temporary pools whose body plan has barely changed in 200 million years, and whose eggs survive dry in the soil for decades. Read the guide →
Fish LC Tripletail Lobotes surinamensis The tripletail floats motionless on its side near the surface, mimicking a dead leaf or drifting debris to ambush prey while hiding from its own predators in plain sight. Read the guide →
Fish LC Triplewart Seadevil Cryptopsaras couesii The triplewart seadevil is found in every ocean except the polar seas, and a single female of this deep-sea anglerfish can carry several permanently fused, parasitic males attached at once. Read the guide →
Fish NE Tripodfish Bathypterois grallator The tripodfish stands on the deep-sea floor on three enormously stretched fin rays, facing the current, and waits, nearly blind, for tiny drifting crustaceans to touch its outstretched fins. Read the guide →
Birds CR Tristan Albatross Diomedea dabbenena The Tristan albatross breeds almost entirely on one remote island where introduced mice have learned to attack chicks many times their own size, a threat now driving the species toward extinction. Read the guide →
Birds VU Tristan Bunting Nesospiza acunhae The Tristan bunting feeds on a far wider variety of seeds than its massive-billed relative Wilkins's bunting, part of an unusual island-bound adaptive radiation compared to Darwin's finches. Read the guide →
Birds NT Tristan Thrush Nesocichla eremita The Tristan thrush occasionally preys on the eggs and chicks of other seabirds, an unusually predatory habit for a thrush found only across the remote Tristan da Cunha island group. Read the guide →
Birds LC Tropical Screech Owl Megascops choliba The tropical screech owl is one of South America's most common and adaptable small owls, equally at home in forest edge, gardens, and city parks. Read the guide →
Birds LC Tropicbird Phaethon spp. The tropicbird trails elegant tail streamers longer than its own body, plunge-dives from height for fish and squid, and walks so poorly on land it only comes ashore to breed. Read the guide →
Fish NE Trout Salmo, Oncorhynchus, and Salvelinus A trout is a cold-water fish of the salmon family, prized by anglers, farmed worldwide, and so widely stocked outside its home range that it now ranks among the most damaging of introduced fish. Read the guide →
Amphibians NE True Frog Ranidae A true frog is a member of the family Ranidae, the long-legged, smooth-skinned, powerful jumpers of pond and stream that most people picture first when they hear the word frog. Read the guide →
Invertebrates LC True Katydid Pterophylla camellifolia The true katydid gave the entire katydid family its common name, its loud, rhythmic "Katy-did, Katy-didn't" call filling summer treetops across the eastern United States after dark. Read the guide →
Birds LC Trumpeter Swan Cygnus buccinator The trumpeter swan is the heaviest waterfowl native to North America, a white bird with a brassy bugling call, hunted down to a few dozen birds by the 1930s and since recovered past 60,000. Read the guide →
Invertebrates LC Tsetse Fly Glossina spp. The tsetse fly gives birth to a single developed larva rather than laying eggs, an unusual strategy among insects, and its bite can spread a disease responsible for widespread illness in Africa. Read the guide →
Birds CR Tuamotu Kingfisher Todiramphus gambieri The Tuamotu kingfisher survives on a single atoll in French Polynesia, one of the rarest birds on Earth, threatened by introduced rats and habitat loss. Read the guide →
Reptiles LC Tuatara Sphenodon punctatus The tuatara of New Zealand looks like a lizard but is the last survivor of an order of reptiles older than the dinosaurs. It has a working third eye, keeps growing for decades, and may live past 100. Read the guide →
Invertebrates NE Tube Anemone Ceriantharia The tube anemone builds a unique fibrous tube from stinging-cell threads found nowhere else in nature, then vanishes into it with startling speed at the first sign of danger. Read the guide →
Fish LC Tube-eye Stylephorus chordatus The tube-eye has tubular, upward-pointing eyes fixed in place and feeds by expanding its mouth into a tiny bubble that sucks in prey like a pipette, a method unlike almost any other fish. Read the guide →
Mammals LC Tube-Lipped Nectar Bat Anoura fistulata The tube-lipped nectar bat has the longest tongue relative to body length of any mammal, coiling it into its rib cage between visits to a single flower species. Read the guide →
Mammals NT Tucuxi Sotalia fluviatilis The tucuxi is often mistaken for a small bottlenose dolphin, sharing rivers with the larger Amazon river dolphin, a distinct species occupying freshwater rivers and coastal waters of South America. Read the guide →
Mammals VU Tufted Ground Squirrel Rheithrosciurus macrotis The tufted ground squirrel of Borneo has a tail so bushy that it is reported to be larger than its body, and a local legend that it kills deer earned it the name vampire squirrel. Read the guide →
Birds LC Tufted Tit-tyrant Anairetes parulus The tufted tit-tyrant sports a spiky, forward-curling crest and constantly flicks its tail, one of the most common and recognisable small birds across Andean and Patagonian scrub. Read the guide →
Birds LC Tufted Titmouse Baeolophus bicolor The tufted titmouse plucks hair directly from live mammals, including sleeping dogs and cats, to line its nest with something softer than anything it could find on the ground. Read the guide →
Birds LC Tui Prosthemadera novaeseelandiae The tui can mimic an extraordinary range of sounds, including other birds and even human speech in captivity, all while carrying a distinctive tuft of curled white feathers at its throat. Read the guide →
Fish NE Tuna Thunnini A tuna is a warm-blooded ocean sprinter that never stops swimming, crossing whole oceans, hitting 70 kilometres an hour in a chase, and keeping its muscles hotter than the water around it. Read the guide →
Amphibians LC Túngara Frog Engystomops pustulosus The tungara frog is a small Central American frog whose males add 'chuck' notes to their whine to woo females — but the same notes summon frog-eating bats. Pairs whip mucus into floating foam nests. Read the guide →
Birds LC Turaco Musophagidae Turacos are the only birds with true green and true red pigments in their feathers. Their red, turacin, contains copper and can partly wash out in heavy rain. Read the guide →
Fish LC Turbot Scophthalmus maximus The turbot lies flat on the seafloor with both eyes on one side like every other flatfish, but stands apart from most relatives as one of the most highly prized flatfish on any European menu. Read the guide →
Birds LC Turkey Vulture Cathartes aura The turkey vulture is a wide-ranging American scavenger that finds carcasses by smell — a rare skill among birds — soars for hours without flapping, and defends itself by projectile vomiting. Read the guide →
Fish VU Turquoise Rainbowfish Melanotaenia lacustris The turquoise rainbowfish shows a vivid blue-green body found naturally only in a single lake in Papua New Guinea, a restricted range that leaves its wild population vulnerable to any change there. Read the guide →
Birds LC Turquoise-browed Motmot Eumomota superciliosa The turquoise-browed motmot is a Central American bird with a bright brow stripe and two long tail feathers ending in bare rackets, which it swings like a pendulum when it spots a predator. Read the guide →
Reptiles NE Turtle Testudines A turtle is a reptile that carries its skeleton on the outside, a bony shell fused to its spine and ribs, a body plan so successful it has barely changed in over 200 million years. Read the guide →
Amphibians LC Turtle Frog Myobatrachus gouldii The turtle frog of southwestern Australia has a tiny head, round body, and stubby limbs, like a shell-less turtle. It burrows head-first into sandy soil, and eats almost nothing but termites. Read the guide →
Invertebrates LC Twelve-Spotted Skimmer Libellula pulchella The twelve-spotted skimmer carries exactly twelve dark spots across its wings, a precise, countable pattern that makes it one of the easiest dragonflies in North America to identify from a distance. Read the guide →
Reptiles LC Twin-Spotted Rattlesnake Crotalus pricei The twin-spotted rattlesnake lives on isolated forested mountaintops surrounded by desert, an unusually cool, high-elevation home for one of the smallest rattlesnake species in the United States. Read the guide →
Reptiles LC Twin-Spotted Spiny Lizard Sceloporus bimaculosus The twin-spotted spiny lizard carries a pair of dark shoulder blotches that give the species its name, sharing its narrow band of desert grassland with several similarly patterned relatives. Read the guide →
Birds LC Two-banded Plover Charadrius falklandicus The two-banded plover is marked by a pair of dark bands across its chest, foraging along the beaches and mudflats of southern South America with the classic run-stop-peck style of its family. Read the guide →
Amphibians LC Two-lined Salamander Eurycea bislineata The two-lined salamander is a slim yellow-brown brook salamander of eastern North America with a dark stripe down each side, a night hunter of stream edges that breathes through its skin. Read the guide →
Invertebrates NE Two-spot Ladybird Adalia bipunctata The two-spot ladybird is a small aphid-eating beetle that comes as red with two black spots or black with red spots, a classic example of colour variation shaped by pollution and competition. Read the guide →
Reptiles VU Two-Striped Garter Snake Thamnophis hammondii The two-striped garter snake has lost most of its southern California stream habitat to drought and development, depending on the same shrinking waterways as other threatened natives. Read the guide →
Invertebrates LC Two-Tailed Swallowtail Papilio multicaudata The two-tailed swallowtail carries two tail extensions per hindwing rather than the single tail typical of most swallowtails, and its large wingspan makes it one of the biggest butterflies out west. Read the guide →
Amphibians LC Two-toed Amphiuma Amphiuma means The two-toed amphiuma is a metre-long aquatic salamander that looks like an eel and has four legs so tiny they are easy to miss. It has one of the biggest genomes of any animal, and it bites hard. Read the guide →
Invertebrates NE Ulysses Butterfly Papilio ulysses The Ulysses butterfly is a large swallowtail with brilliant electric-blue upper wings that flashes through the rainforests of northeastern Australia and New Guinea and is an emblem of Queensland. Read the guide →
Birds VU Umbrellabird Cephalopterus A male umbrellabird inflates a long, feathered wattle hanging from his throat, while a forward crest shades his bill, giving him one of the strangest silhouettes of any rainforest bird. Read the guide →
Fish EN Undulate Ray Raja undulata The undulate ray is a handsome ray of the north-eastern Atlantic whose brown back is patterned with pale wavy lines, and which has been heavily fished and is now endangered outside a few strongholds. Read the guide →
Birds LC Undulated Antpitta Grallaria squamigera The undulated antpitta is heard far more often than it is seen, its loud call carrying through Andean forest while the bird itself stays hidden on the ground. Read the guide →
Invertebrates NE Unicorn Mantis Empusa pennata The unicorn mantis carries a single pointed, horn-like projection rising from its head, used alongside elaborate feathery antennae in courtship and camouflage against vegetation. Read the guide →
Amphibians LC Upland Chorus Frog Pseudacris feriarum The upland chorus frog calls with a sound like running a fingernail down the teeth of a comb, breeding in temporary ponds during the very first mild nights of early spring. Read the guide →
Birds LC Upland Goose Chloephaga picta The upland goose is the most common and widespread of the Patagonian geese, grazing grassland far from the coast rather than sticking to shoreline habitat like several of its close relatives. Read the guide →
Fish LC Upside-Down Catfish Synodontis nigriventris The upside-down catfish spends much of its life swimming belly-up, an inverted posture that lets it graze algae and insects from the undersides of leaves and the water's surface film. Read the guide →
Invertebrates LC Upside-Down Jellyfish Cassiopea spp. The upside-down jellyfish rests bell-down on the seafloor and pulses gently, farming its own food through symbiotic algae living in its tissue rather than actively hunting prey like most jellyfish. Read the guide →
Mammals VU Urial Ovis vignei The urial's males grow a long, shaggy ruff of hair along the throat during the breeding season, a wild sheep of dry hillsides across Central and South Asia. Read the guide →
Reptiles LC Uromastyx Uromastyx A uromastyx is a stocky, herbivorous desert lizard of North Africa and the Middle East with a short, powerful, spike-covered tail that it uses as a club and a plug for its burrow entrance. Read the guide →
Mammals EN Utah Prairie Dog Cynomys parvidens The Utah prairie dog is the smallest prairie dog, found only in southwestern Utah, where plague, farming, and development have left this hibernating species Endangered. Read the guide →
Amphibians VU Valdina Farms Salamander Eurycea troglodytes The Valdina Farms salamander was first described from a sinkhole altered by quarrying, and its entire known population still depends on groundwater flowing through that same disturbed cave system. Read the guide →
Amphibians LC Valley and Ridge Salamander Plethodon hoffmani The Valley and Ridge salamander takes its name from the long, parallel mountain-and-valley landscape of the central Appalachians it calls home. Read the guide →
Amphibians DD Vampire Flying Frog Rhacophorus vampyrus The vampire flying frog is a Vietnamese tree frog discovered only in 2010 whose tadpoles have hooked black fangs used to scrape food from the walls of the water-filled tree holes where they develop. Read the guide →
Invertebrates NE Vampire Moth Calyptra thalictri The vampire moth is one of a handful of moths whose males pierce the skin of large mammals and drink blood, using a barbed tongue evolved for puncturing tough fruit. Females feed on fruit only. Read the guide →
Invertebrates NE Vampire Shrimp Atyopsis moluccensis The vampire shrimp catches food by holding out a pair of fan-shaped appendages to filter tiny particles directly from the current, rather than scavenging the substrate like most shrimp. Read the guide →
Invertebrates NE Vampire Squid Vampyroteuthis infernalis The vampire squid is a small deep-sea cephalopod that is neither a squid nor an octopus. It lives where there is almost no oxygen, cannot make ink, and feeds on "marine snow" drifting down from above. Read the guide →
Amphibians NT Van Dyke's Salamander Plethodon vandykei Van Dyke's salamander survives in a narrow strip of Washington state near cold mountain streams and waterfall splash zones, going through life with no aquatic larval stage at all. Read the guide →
Mammals CR Vaquita Phocoena sinus The vaquita is the world's smallest and most endangered marine mammal — a shy porpoise of the northern Gulf of California, with about 10 individuals left, all dying in illegal fishing nets. Read the guide →
Birds LC Variable Hawk Geranoaetus polyosoma The variable hawk earns its name from an extraordinary range of plumage patterns across individuals, making it one of the most difficult South American raptors to identify with confidence. Read the guide →
Birds LC Vasa Parrot Coracopsis vasa The vasa parrot is an unusually dark-plumaged parrot that turns bald during breeding season, and females compete to mate with multiple males in a reversal of typical bird roles. Read the guide →
Invertebrates LC Vase Sponge Ircinia campana A vase sponge grows as a single large, upright tube that can filter an enormous volume of seawater every day, drawing water in through its walls and expelling it in a steady jet from the open top. Read the guide →
Birds LC Veery Catharus fuscescens The veery sings a haunting, downward-spiraling series of notes using both sides of its voice box at once, layering two separate pitches together into a single flute-like phrase. Read the guide →
Amphibians EX Vegas Valley Leopard Frog Lithobates fisheri The Vegas Valley leopard frog once lived only in the desert springs beneath what is now Las Vegas, and disappeared for good sometime around the 1940s. Read the guide →
Reptiles LC Veiled Chameleon Chamaeleo calyptratus The veiled chameleon has a tall bony helmet that funnels dew into its mouth, letting it live in the dry mountains of Yemen. It is the most commonly kept pet chameleon and one of the hardier ones. Read the guide →
Invertebrates NE Velvet Ant Dasymutilla and related genera The velvet ant is not an ant but a wingless wasp, and the female delivers one of the most painful stings of any insect — hence the nickname 'cow killer'. Read the guide →
Invertebrates NE Velvet Swimming Crab Necora puber The velvet swimming crab is a fierce, red-eyed crab of north-eastern Atlantic rocky shores covered in fine velvety hair, whose back legs are flattened into paddles for swimming. Read the guide →
Invertebrates NE Velvet Worm Onychophora The velvet worm is a soft, caterpillar-like predator that catches prey by firing two jets of glue from nozzles beside its mouth. Its body plan has barely changed in 500 million years. Read the guide →
Invertebrates NE Vent Barnacle Neolepas zevinae The vent barnacle clusters densely around hydrothermal vent openings, filtering chemical-rich water and bacteria directly from the current rather than the plankton typical of shallow-water barnacles. Read the guide →
Invertebrates NE Vent Crab Bythograea thermydron The vent crab scavenges and hunts around scalding hydrothermal vents, balancing close enough to the warm, chemical-rich water its prey depends on without straying into water hot enough to kill it. Read the guide →
Invertebrates NE Vent Limpet Lepetodrilus The vent limpet grazes on bacterial mats growing across hydrothermal vent surfaces, gathering in dense clusters wherever chemical-rich water supports the microbial food it depends on. Read the guide →
Invertebrates LC Vent Mussel Bathymodiolus The vent mussel gets most of its nutrition not from filtering food out of the water but from bacteria living inside its own gills, which convert toxic vent chemicals directly into energy. Read the guide →
Invertebrates LC Vent Shrimp Rimicaris exoculata The vent shrimp has no image-forming eyes at all, instead carrying a light-sensing organ on its back tuned to detect the faint thermal glow of a hydrothermal vent from a distance. Read the guide →
Invertebrates NE Venus Flytrap Anemone Actinoscyphia The venus flytrap anemone closes its ring of tentacles around passing prey like the plant it is named for, snapping shut on the deep seafloor rather than trapping insects on land. Read the guide →
Invertebrates NE Venus's Flower Basket Euplectella aspergillum Venus's flower basket is a deep-sea glass sponge that weaves an intricate lattice tube of natural fibre optics and often shelters a pair of shrimp sealed inside it for life. Read the guide →
Invertebrates NE Venus's Girdle Cestum veneris The Venus's girdle flattens its body into a long, translucent ribbon that ripples with rainbow light as it swims, one of the most strikingly shaped comb jellies drifting through the open ocean. Read the guide →
Birds LC Verdin Auriparus flaviceps The verdin builds a spiky, thorn-covered nest that looks like debris caught in a bush, and a pair may build several throughout the year, using different ones for roosting, breeding, and shelter. Read the guide →
Birds LC Vermilion Flycatcher Pyrocephalus rubinus The male vermilion flycatcher performs a fluttering, sky-facing display flight while singing, showing off a scarlet-red body that ranks among the most vivid colors of any North American flycatcher. Read the guide →
Mammals EN Verreaux's Sifaka Propithecus verreauxi Verreaux's sifaka can barely walk on the ground, instead crossing open spaces with a sideways hopping dance unlike almost any other primate's gait. Read the guide →
Mammals LC Vervet Monkey Chlorocebus pygerythrus The vervet monkey gives entirely different alarm calls for leopards, eagles, and snakes, each one triggering a distinct, appropriate escape response in listeners. Read the guide →
Birds LC Vesper Sparrow Pooecetes gramineus The vesper sparrow sings its clearest songs at dusk, a habit distinctive enough among grassland sparrows to give the species a name referencing evening prayer. Read the guide →
Invertebrates LC Viceroy Butterfly Limenitis archippus The viceroy butterfly was long believed to be a harmless mimic copying the toxic monarch for protection, until research showed the viceroy is itself genuinely distasteful too. Read the guide →
Mammals LC Vicuna Vicugna vicugna The vicuna produces the finest and most valuable wool of any animal on Earth, a prize that once drove it to near extinction before international protection brought about a remarkable recovery. Read the guide →
Invertebrates NE Vietnamese Centipede Scolopendra subspinipes The Vietnamese centipede delivers a venomous bite powerful enough to cause serious pain and swelling in a person, one of the largest and most aggressive centipede species kept in the pet trade. Read the guide →
Amphibians LC Vietnamese Mossy Frog Theloderma corticale The Vietnamese mossy frog is covered in green-and-black bumps, ridges, and spines that make it look exactly like a clump of moss on wet rock. Startled, it tucks in its limbs and plays dead as a ball. Read the guide →
Fish LC Vimba Bream Vimba vimba The vimba bream is a slender, silvery carp relative with a pointed, overhanging snout that feeds on the bottom of rivers and estuaries and runs upstream to spawn on gravel. Read the guide →
Reptiles LC Vine Snake Ahaetulla A vine snake is an extremely thin, mildly venomous Asian tree snake so slender it is easily mistaken for a real vine, and it is one of very few snakes with forward-facing, true binocular vision. Read the guide →
Invertebrates NE Vine Weevil Otiorhynchus sulcatus The vine weevil is a small, black, flightless beetle whose adults are nearly all females that reproduce alone, and whose white root-eating grubs are among the worst pests of pot plants and soft fruit. Read the guide →
Invertebrates NE Vinegaroon Thelyphonida The vinegaroon has no venom and no sting, but when disturbed it aims its whip-like tail at the threat and sprays a fine mist that is up to 84% acetic acid, smelling strongly of vinegar. Read the guide →
Invertebrates NE Violet Ground Beetle Carabus violaceus The violet ground beetle is a large, glossy black beetle with a violet sheen along its edges, a flightless night hunter of slugs and worms in gardens, hedges, and woods. Read the guide →
Invertebrates NE Violet Sea Snail Janthina janthina The violet sea snail is a fragile, violet-shelled snail that floats upside down at the ocean surface on a raft of bubbles it makes itself and hunts the drifting jellyfish-like animals there. Read the guide →
Invertebrates NE Violin Beetle Mormolyce phyllodes The violin beetle's body is flattened into a broad, instrument-shaped outline, letting it slip into the narrow space beneath bracket fungus to hunt. Read the guide →
Invertebrates NE Violin Mantis Gongylus gongylodes The violin mantis carries an elongated body shaped remarkably like the instrument it's named for, swaying gently from side to side to mimic a leaf moving in the breeze. Read the guide →
Reptiles NE Viper Viperidae A viper is a venomous snake with long hinged fangs that fold flat against the roof of the mouth and swing forward to stab, injecting a venom that mostly destroys tissue and blood rather than nerves. Read the guide →
Fish LC Viperfish Chauliodus sloani The viperfish has fangs so long they will not fit in its mouth, curving back near its eyes when the jaws close. It hangs motionless in the deep sea with a glowing lure on its back to draw prey close. Read the guide →
Birds LC Vireo Vireo A vireo is a small, plainly coloured American songbird often mistaken for a warbler, distinguished by a slower, more deliberate foraging style and a sturdier, slightly hooked bill. Read the guide →
Mammals LC Virginia Opossum Didelphis virginiana The Virginia opossum is North America's only marsupial. It has more teeth than any other land mammal on the continent, is largely immune to pit-viper venom, and plays dead as an involuntary reflex. Read the guide →
Birds LC Virginia Rail Rallus limicola The Virginia rail has a body flattened from side to side, an adaptation that lets it slip between dense marsh reeds without disturbing a single stalk, living up to the phrase "thin as a rail." Read the guide →
Birds LC Virginia's Warbler Leiothlypis virginiae Virginia's warbler nests directly on the ground within dense mountain scrub, a low-lying strategy that leaves its eggs and chicks more exposed than the elevated nests most warblers rely on. Read the guide →
Mammals CR Visayan Warty Pig Sus cebifrons The Visayan warty pig is a Critically Endangered Philippine wild pig whose males grow a long crest and facial warts in the breeding season, now restricted to a few forest remnants on two islands. Read the guide →
Reptiles LC Viviparous Lizard Zootoca vivipara The viviparous lizard is the most widespread lizard on Earth, ranging from Ireland to the Pacific and into the Arctic, and most populations give birth to live young rather than laying eggs. Read the guide →
Birds LC Vogelkop Bowerbird Amblyornis inornata The male Vogelkop bowerbird is a plain brown bird that builds a thatched hut up to a metre tall with a mossy front lawn, then decorates it with objects sorted by colour to win a mate. Read the guide →
Mammals EN Volcano Rabbit Romerolagus diazi The volcano rabbit survives only on the slopes of a handful of volcanoes near Mexico City, one of the smallest rabbit species in the world and among the most geographically restricted. Read the guide →
Invertebrates NE Vulcanoctopus Vulcanoctopus hydrothermalis Vulcanoctopus is the only known octopus adapted specifically to life around hydrothermal vents, lacking the ink sac and skin-colour-changing cells most other octopuses depend on for defence. Read the guide →
Birds EN Vulture Cathartidae and Old World vultures A vulture is a large bird that lives almost entirely on carrion, soaring for hours to find it; its bald head and battery-acid gut let it eat rotten meat that would poison almost anything else. Read the guide →
Birds LC Vulturine Guineafowl Acryllium vulturinum The vulturine guineafowl is the largest, most colourful guineafowl, with a bare vulture-like head and cobalt-blue breast. Its flocks maintain stable, multi-level societies unusual among birds. Read the guide →
Birds LC Wagtail Motacilla A wagtail is a slender songbird named for its habit of constantly bobbing its long tail up and down while walking, a near-continuous motion whose exact purpose is still debated. Read the guide →
Fish LC Wahoo Acanthocybium solandri The wahoo is a long, torpedo-shaped relative of the mackerels and tunas, one of the fastest fish in the sea, prized by anglers and cooks and known in Hawaii as ono, meaning good to eat. Read the guide →
Fish LC Walking Catfish Clarias batrachus The walking catfish breathes air, survives out of water for hours, and crosses wet ground between ponds by wriggling on its stiff fins, which has made it a fast-spreading invader in Florida. Read the guide →
Invertebrates LC Wall Brown Lasiommata megera The wall brown is a sun-loving orange butterfly marked with dark tiger-like barring and eyespots, which basks on warm walls and bare ground and has declined sharply across much of Britain. Read the guide →
Amphibians LC Wallace's Flying Frog Rhacophorus nigropalmatus Wallace's flying frog is a large Southeast Asian tree frog with huge webbed hands and feet spread like parachutes to glide up to 15 metres between trees, named for the naturalist who described it. Read the guide →
Amphibians LC Wallace's Flying Frog Rhacophorus nigropalmatus Wallace's flying frog glides between rainforest trees on huge webbed feet and skin flaps, steering and braking to land, and comes to the forest floor only to breed in foam nests over wallow pools. Read the guide →
Fish LC Walleye Sander vitreus The walleye is a large member of the perch family with a mirror behind its eye that lets it hunt in near-darkness; it is the most prized freshwater food fish across much of the northern US and Canada. Read the guide →
Mammals VU Walrus Odobenus rosmarus The walrus uses its metre-long tusks to haul onto ice and its 700 whiskers to find clams on the dark seabed. Learn how this Arctic giant feeds, why it turns pink, and how ice loss threatens it. Read the guide →
Birds VU Wandering Albatross Diomedea exulans The wandering albatross has the longest wingspan of any living bird and can glide for days without flapping, circling the globe on the wind. Learn how it flies so efficiently and why it is Vulnerable. Read the guide →
Amphibians LC Wandering Salamander Aneides vagrans The wandering salamander lives high in the crowns of California's redwoods, and when it falls it spreads its limbs to slow the drop and steer itself back toward the trunk, effectively skydiving. Read the guide →
Birds LC Warbling Vireo Vireo gilvus The warbling vireo is one of the plainest-looking songbirds in North America, easy to overlook entirely, yet it sings an almost continuous, cheerful song from high in the treetops all season. Read the guide →
Fish LC Warmouth Lepomis gulosus The warmouth gets its name from an unusually large mouth for a sunfish, and it hunts other fish more aggressively than most of its panfish relatives while tolerating murky, weedy water they avoid. Read the guide →
Fish LC Warpaint Shiner Luxilus coccogenis A breeding male warpaint shiner develops streaks of vivid red and orange across its head and fins, a striking seasonal pattern bold enough to have earned the species its distinctive common name. Read the guide →
Invertebrates NE Wasp Vespidae and relatives A wasp is a stinging relative of bees and ants, most species solitary hunters that paralyse prey for their young, and collectively one of the biggest natural checks on insect numbers. Read the guide →
Invertebrates NE Wasp Beetle Clytus arietis The wasp beetle is a harmless longhorn beetle with a black-and-yellow banded body that mimics a wasp, even moving and waving its antennae like one, to scare off predators. Read the guide →
Invertebrates NE Wasp Spider Argiope bruennichi The wasp spider is banded in bold black, yellow, and white stripes closely resembling a wasp, and weaves a distinctive zigzag ribbon through the centre of its web. Read the guide →
Fish LC Watchman Goby Cryptocentrus The watchman goby stands guard at the entrance of a burrow dug and maintained by a nearly blind pistol shrimp, a close partnership where neither species comes out ahead without the other. Read the guide →
Invertebrates LC Water Boatman Corixidae A water boatman is a small oval water bug that swims right-way-up and rows with hair-fringed hind legs, feeding mostly on algae, and one tiny kind is the loudest animal on Earth for its size. Read the guide →
Mammals VU Water Deer Hydropotes inermis The water deer is the only deer species that grows no antlers at all in either sex, relying instead on long, visible tusks that have earned it an occasional nickname as the vampire deer. Read the guide →
Invertebrates LC Water Flea Daphnia A water flea is a transparent, jerkily swimming crustacean whose beating heart is visible through its shell, and it can switch from cloning itself to sexual reproduction when its pond turns hostile. Read the guide →
Invertebrates NE Water Louse Asellus aquaticus The water louse is a flat, grey-brown aquatic relative of the woodlouse that crawls over mud and weed in ponds and slow rivers, feeds on rotting plant matter, and tolerates poor water. Read the guide →
Mammals LC Water Opossum Chironectes minimus The water opossum is the only truly aquatic marsupial, swimming with webbed hind feet, and even males carry a sealable pouch that protects them while diving. Read the guide →
Reptiles LC Water Python Liasis fuscus The water python is a brown, iridescent-scaled Australian python of northern floodplains and billabongs that hunts rats, birds, and reptiles at night and reaches around three metres in length. Read the guide →
Birds LC Water Rail Rallus aquaticus The water rail produces a call so pig-like that its unearthly squeals from deep within a reed bed have convinced many a passerby that something else entirely was hiding in the marsh. Read the guide →
Invertebrates LC Water Scorpion Nepidae A water scorpion is a predatory water bug that grabs prey with folding mantis-like front legs and breathes through a long tail-like tube, and despite the name it is not a scorpion and cannot sting. Read the guide →
Reptiles LC Water Snake Nerodia A water snake is a non-venomous North American snake of ponds and rivers, often killed because it is mistaken for a cottonmouth, though it has round pupils, no facial pits, and swims at the surface. Read the guide →
Invertebrates LC Water Strider Gerridae The water strider walks on the surface of ponds and even the open ocean, held up by water-repellent hairs on its legs; it hunts by feeling the ripples of insects that fall onto the water. Read the guide →
Mammals VU Water Vole Arvicola amphibius The water vole, the real-life inspiration for Ratty in The Wind in the Willows, has vanished from most of Britain since American mink escaped into the wild. Read the guide →
Amphibians LC Water-holding Frog Cyclorana platycephala The water-holding frog of arid Australia stores water in its body, buries itself, and seals into a cocoon of shed skin to wait out drought. Desert peoples dug them up and squeezed them for a drink. Read the guide →
Mammals LC Waterbuck Kobus ellipsiprymnus The waterbuck secretes an oily, musky substance that may make its meat unpalatable to predators, a shaggy African antelope with a white target-like ring around its rump. Read the guide →
Birds CR Waved Albatross Phoebastria irrorata The waved albatross is the only albatross species found in the tropics, breeding almost entirely on one Galapagos island and launching itself into flight by running off a cliff edge. Read the guide →
Amphibians LC Waxy Monkey Tree Frog Phyllomedusa sauvagii The waxy monkey tree frog survives the dry South American Chaco by coating itself in a waxy secretion it wipes on with its own legs, then basking in full sun like a reptile rather than hiding from it. Read the guide →
Birds LC Weaver Ploceidae A weaver is a small yellow African bird whose male ties and knots a hanging nest from strips of grass; the family includes the world's largest bird nest and the most numerous wild bird on Earth. Read the guide →
Reptiles LC Web-footed Gecko Pachydactylus rangei The web-footed gecko lives on Namib dunes, where webbed feet let it run on soft sand and dig. Its skin is nearly translucent, and it licks fog droplets off its own eyes to drink. Read the guide →
Mammals EN Web-footed Tenrec Limnogale mergulus The web-footed tenrec traded the spiny coat of its relatives for dense, waterproof fur, becoming the only tenrec species adapted to hunting underwater in Madagascar's fast-flowing mountain streams. Read the guide →
Amphibians NT Web-toed Salamander Hydromantes A web-toed salamander is a lungless rock-dwelling salamander of California and southern Europe that climbs with its tail as a fifth limb and has one of the fastest tongues of any vertebrate. Read the guide →
Amphibians LC Webless Salamander Plethodon websteri The webless salamander is named for a trait most salamanders take for granted, toes with no webbing at all, setting it apart from close relatives that rely on webbed feet. Read the guide →
Invertebrates NE Webspinner Embioptera The webspinner is named for spinning silk from glands in its own front legs, building tunnel galleries it can race through backward just as fast as forward. Read the guide →
Mammals LC Weddell Seal Leptonychotes weddellii The Weddell seal can dive below 600 metres and stay submerged over an hour, the southernmost-breeding mammal on Earth, wearing its teeth down from years scraping breathing holes through Antarctic ice. Read the guide →
Birds LC Wedge-Billed Woodcreeper Glyphorynchus spirurus The wedge-billed woodcreeper is the smallest and most abundant woodcreeper species, using a short, straight, wedge-shaped bill unlike the long curved bills of most of its relatives. Read the guide →
Fish LC Weedy Seadragon Phyllopteryx taeniolatus The weedy seadragon is a seahorse relative from southern Australia, patterned in red, purple, and gold with leaf-like flaps. Like all its family, the male carries the eggs on his tail, in the open. Read the guide →
Fish LC Weeverfish Trachinus draco The weeverfish buries itself in sand with only its eyes and venomous spines showing, waiting for prey — and for unlucky waders to step on it. It causes more stings than any other European fish. Read the guide →
Amphibians LC Wehrle's Salamander Plethodon wehrlei Wehrle's salamander shelters deep within rock crevices and talus slopes, sometimes near cave entrances, going through life with no aquatic larval stage at all. Read the guide →
Birds VU Weka Gallirallus australis The weka is a large, flightless New Zealand rail notorious for boldly stealing shiny or unattended objects from campsites, an opportunistic curiosity that matches its equally varied diet. Read the guide →
Amphibians NT Weller's Salamander Plethodon welleri Weller's salamander survives only on a handful of high-elevation peaks in the southern Appalachians, restricted to spruce-fir forest that has been steadily shrinking as the climate warms. Read the guide →
Fish LC Wels Catfish Silurus glanis The wels catfish is Europe's largest freshwater fish — a 2-to-3-metre, whiskered ambush predator that hunts by smell and electric sense in the dark, and in France it hunts pigeons on land. Read the guide →
Mammals VU West Indian Manatee Trichechus manatus The West Indian manatee is a slow, gentle aquatic herbivore that eats a tenth of its body weight in plants a day and gathers at warm-water springs to survive the winter. Read the guide →
Mammals CR Western Black Crested Gibbon Nomascus concolor The western black crested gibbon is one of the rarest primates on Earth, its entire population confined to a handful of isolated mountain forest patches. Read the guide →
Reptiles LC Western Brown Snake Pseudonaja nuchalis The western brown snake, or gwardar, is a fast, variably coloured Australian snake of dry country with a potent venom, found across the arid centre, north, and west of the continent. Read the guide →
Birds LC Western Capercaillie Tetrao urogallus The western capercaillie is the largest grouse, a turkey-sized bird of old conifer forest whose displaying male fans his tail and pours out a clicking, cork-popping song. Read the guide →
Reptiles LC Western Diamondback Rattlesnake Crotalus atrox The western diamondback is behind more serious snakebites than any other snake in the United States, not because its venom is the strongest but because it is large, common, and stands its ground. Read the guide →
Invertebrates LC Western Drywood Termite Incisitermes minor The western drywood termite needs no soil contact at all, living entirely inside the dry wood it eats and giving itself away only through tiny six-sided pellets pushed out through kick holes. Read the guide →
Reptiles LC Western Fence Lizard Sceloporus occidentalis The western fence lizard, the blue-belly of the American West, does push-ups on rocks and fences, and a protein in its blood kills the Lyme disease bacterium inside feeding ticks. Read the guide →
Reptiles LC Western Fox Snake Pantherophis vulpinus The western fox snake vibrates its tail against dry vegetation to produce a buzz convincing enough that many people mistake this harmless constrictor for a rattlesnake and kill it out of fear. Read the guide →
Mammals CR Western Gorilla Gorilla gorilla The western gorilla is the largest primate and shares about 98% of its DNA with humans. Learn how silverback-led troops live, what gorillas eat, and why the species is Critically Endangered. Read the guide →
Mammals LC Western Grey Kangaroo Macropus fuliginosus The western grey kangaroo grazes in mobs across southern Australia, distinguished from its eastern relative by a stronger, more musky scent that gives it a blunt nickname. Read the guide →
Reptiles LC Western Hognose Snake Heterodon nasicus The western hognose snake is a small, harmless prairie burrower with an upturned digging snout that hisses like a cobra when threatened and, if that fails, rolls over and convincingly plays dead. Read the guide →
Mammals EN Western Hoolock Gibbon Hoolock hoolock The western hoolock gibbon is an Endangered ape of northeastern India, Bangladesh, and Myanmar, the only ape in India, whose pairs sing duets from the forest canopy. Read the guide →
Birds LC Western Kingbird Tyrannus verticalis The western kingbird perches boldly on roadside wires across the open West, hiding an orange-red crown patch that only appears during aggressive confrontations with rivals. Read the guide →
Mammals CR Western Long-beaked Echidna Zaglossus bruijnii The western long-beaked echidna is a Critically Endangered egg-laying mammal of New Guinea's mountain forests, with a long curved snout and a spiny tongue for catching earthworms. Read the guide →
Mammals LC Western Mastiff Bat Eumops perotis The western mastiff bat is the largest bat in North America, a fast, high-flying insect hunter whose low-pitched calls are loud enough for people to hear. Read the guide →
Amphibians LC Western Narrowmouth Toad Gastrophryne olivacea The western narrowmouth toad survives in drier habitat than its eastern relative, tolerating arid grassland across the central and southwestern US by staying underground most of the year. Read the guide →
Mammals NT Western Quoll Dasyurus geoffroii The western quoll once ranged across roughly 70 percent of Australia, but now survives naturally only in a small southwestern corner, propped up by active reintroductions. Read the guide →
Amphibians LC Western Red-Backed Salamander Plethodon vehiculum The western red-backed salamander is one of the most common salamanders in Pacific Northwest forests, living beneath nearly every well-decayed log despite having no lungs and no need for water. Read the guide →
Reptiles LC Western Ribbon Snake Thamnophis proximus The western ribbon snake stays close to water's edge without fully submerging, carrying three bold stripes down a slender body built for speed rather than for confrontation. Read the guide →
Birds LC Western Screech-Owl Megascops kennicottii The western screech-owl produces an accelerating series of hollow whistles rather than a trill, a call so different from its eastern relative that voice alone reliably separates the two species. Read the guide →
Reptiles LC Western Skink Plestiodon skiltonianus The western skink flashes a bright blue tail as a juvenile, drawing attacks away from its body toward a tail it can shed and regrow, a common but rarely appreciated lizard across the American West. Read the guide →
Amphibians VU Western Spadefoot Spea hammondii The western spadefoot is a California native that spends most of the year buried underground, surfacing only after heavy rain to breed in pools that may dry up again within days. Read the guide →
Reptiles CR Western Swamp Turtle Pseudemydura umbrina The western swamp turtle is a tiny, brown freshwater turtle found only in a few seasonal swamps near Perth, Australia's most endangered reptile, saved from the brink by captive breeding. Read the guide →
Birds LC Western Tanager Piranga ludoviciana A male western tanager's red head comes from a rare pigment absorbed through diet rather than made by the bird's own body, unusual among songbirds. Read the guide →
Reptiles LC Western Terrestrial Garter Snake Thamnophis elegans The western terrestrial garter snake ranges higher into the mountains than almost any other North American snake, found active at elevations where snow lingers well into summer. Read the guide →
Amphibians NT Western Toad Anaxyrus boreas The western toad climbs higher into the mountains than almost any other North American amphibian, and unlike most toads, its males have no mating call at all — no vocal sac, no chorus, just silence. Read the guide →
Birds VU Western Tragopan Tragopan melanocephalus The western tragopan inflates a vivid blue-and-red throat wattle and raises two fleshy blue horns above its head, one of the most dramatic courtship displays found in any pheasant. Read the guide →
Reptiles LC Western Whiptail Aspidoscelis tigris The western whiptail is one of the most widespread lizards of the American Southwest, a fast, restless forager whose bold spotted pattern inspired its alternate name, the tiger whiptail. Read the guide →
Reptiles LC Western Worm Snake Carphophis vermis The western worm snake spends nearly its life buried in soil, so committed to living underground that its tiny eyes are little more than dark spots for sensing light rather than forming images. Read the guide →
Birds VU Westland Petrel Procellaria westlandica The Westland petrel breeds only in forested hills on New Zealand's South Island, one of the very few burrow-nesting seabirds to breed inland under a forest canopy rather than on open coastal ground. Read the guide →
Mammals NE Whale Cetacea A whale is a mammal that returned to the sea so completely it can no longer leave it, and the group includes the blue whale, the largest animal that has ever lived. Read the guide →
Fish EN Whale Shark Rhincodon typus The whale shark is the largest fish in the sea — a 12-metre, spotted filter feeder that strains plankton and is completely harmless to people. Learn how it feeds, breeds, and why it's Endangered. Read the guide →
Fish LC Whalefish Cetomimidae The whalefish looks so different between males and females that scientists once classified them as three separate fish families, until DNA evidence revealed them to be the same species. Read the guide →
Invertebrates LC Whelk Buccinidae The whelk drills a hole through a clam's shell using acid and a rasping tongue, or simply pries the shell open with the edge of its own, patiently working out every meal. Read the guide →
Birds NT Whip-poor-will Antrostomus vociferus The whip-poor-will is named for its own call, a loud, repetitive whistle heard far more often than the bird itself is ever seen, camouflaged perfectly against leaf litter through the day. Read the guide →
Reptiles LC Whiptail Lizard Aspidoscelis A whiptail lizard is a slender, restless, fast-running forager of dry open country in the Americas, and about a third of its species are all female, reproducing by cloning themselves. Read the guide →
Invertebrates LC Whirligig Beetle Gyrinidae The whirligig beetle spins in tight, erratic circles across the water surface, and each of its eyes is split in two, one half watching above the surface and the other watching below at once. Read the guide →
Birds LC Whiskered Tern Chlidonias hybrida The whiskered tern is a freshwater marsh specialist like its close relative the black tern, but keeps a sharp white cheek stripe against dark grey underparts rather than turning almost entirely black. Read the guide →
Birds LC Whistling Heron Syrigma sibilatrix The whistling heron hunts insects across dry grassland far from water more often than most herons, named for its distinctive whistling call. Read the guide →
Invertebrates LC White Admiral Limenitis camilla The white admiral is a graceful woodland butterfly with a bold white band across dark wings, whose caterpillar feeds on honeysuckle and spends the winter in a tiny rolled-leaf shelter. Read the guide →
Fish LC White Bass Morone chrysops The white bass forms surface-churning feeding frenzies while chasing shad in open water, and its hybrid with the striped bass is stocked widely as the wiper. Read the guide →
Birds VU White Bellbird Procnias albus The male white bellbird makes the loudest call ever measured in a bird, around 125 decibels, and aims his loudest, shortest blasts point-blank at a female perched right beside him. Read the guide →
Fish LC White Catfish Ameiurus catus The white catfish sits squarely between its larger and smaller relatives in size, with a forked tail that instantly separates it from the rounder-tailed bullheads sharing its own genus. Read the guide →
Fish EN White Cloud Mountain Minnow Tanichthys albonubes The white cloud mountain minnow was feared extinct in the wild for decades after its single known stream was developed, surviving mainly through aquarium populations. Read the guide →
Fish LC White Crappie Pomoxis annularis The white crappie tolerates murkier, more turbid water better than its close relative the black crappie, and a count of dorsal fin spines is the most reliable way anglers separate the two. Read the guide →
Fish VU White Marlin Kajikia albida The white marlin is one of the smaller members of the marlin family, a fast, acrobatic billfish prized by recreational anglers for a fight that often includes spectacular leaps clear of the water. Read the guide →
Fish LC White Perch Morone americana The white perch tolerates fresh, brackish, and salty water within a single lifetime, an adaptable temperate bass relative whose name misleadingly links it to a completely different fish family. Read the guide →
Mammals NT White Rhinoceros Ceratotherium simum The white rhino is the second-largest land animal and a conservation rollercoaster — saved from under 100 animals a century ago, then hammered by a poaching crisis for its horn. Read the guide →
Birds LC White Stork Ciconia ciconia The white stork is the bird behind the storks-deliver-babies myth, nesting on chimneys and rooftops across Europe and returning to the same nest for decades. One bird proved storks winter in Africa. Read the guide →
Fish LC White Sturgeon Acipenser transmontanus The white sturgeon is the largest freshwater fish in North America, an armoured survivor from the age of dinosaurs that can pass 6 metres, weigh over 800 kg, and live more than a century. Read the guide →
Fish LC White Sucker Catostomus commersonii The white sucker feeds by vacuuming the bottom sediment through a downturned, fleshy mouth, sorting out edible particles and expelling the rest in a steady cloud of disturbed silt. Read the guide →
Birds NT White-backed Woodpecker Dendrocopos leucotos The white-backed woodpecker depends so heavily on old-growth forest full of standing dead wood that its presence or absence is often used as an indicator of genuine forest health across Europe. Read the guide →
Birds LC White-bellied Storm-petrel Fregetta grallaria The white-bellied storm-petrel patters its feet across the ocean surface while foraging, a behaviour so distinctive it helped give the entire storm-petrel family its name. Read the guide →
Birds LC White-Breasted Nuthatch Sitta carolinensis The white-breasted nuthatch forages headfirst down tree trunks, a habit rare among North American birds that lets it spot insects hidden in bark crevices that upward-climbing birds tend to miss. Read the guide →
Birds LC White-capped Pionus Pionus seniloides The white-capped pionus shows pale feathers on the forehead that give it a prematurely aged appearance, a lesser-known parrot of Andean cloud forest. Read the guide →
Birds VU White-chinned Petrel Procellaria aequinoctialis The white-chinned petrel is among the seabirds most frequently killed as bycatch on longline fishing hooks, a large, dark seabird that readily follows fishing vessels across the Southern Ocean. Read the guide →
Invertebrates EN White-clawed Crayfish Austropotamobius pallipes The white-clawed crayfish is Britain's only native freshwater crayfish, a small nocturnal inhabitant of clean, hard-water streams that is endangered by plague carried by invading American crayfish. Read the guide →
Birds LC White-collared Swift Streptoprocne zonaris The white-collared swift is one of the largest swift species, identified by a bright white band around the neck, roosting in caves and behind waterfalls across the Americas. Read the guide →
Birds LC White-crested Elaenia Elaenia albiceps The white-crested elaenia undertakes one of the longest migrations of any South American songbird, breeding in Patagonia and travelling as far as the Amazon basin for the winter. Read the guide →
Mammals LC White-eared Opossum Didelphis albiventris The white-eared opossum adapts readily to nearly any habitat it encounters, a common and widespread South American marsupial identified by its pale ears and face. Read the guide →
Birds LC White-Eye Zosterops spp. The white-eye has colonized more remote Pacific islands than almost any other songbird, splitting into new species again and again in a pattern that made the genus a favourite case study in evolution. Read the guide →
Mammals VU White-Faced Capuchin Cebus capucinus The white-faced capuchin cracks open nuts and shellfish with stone tools, passing specific techniques down through generations within a single troop. Read the guide →
Birds LC White-faced Storm-petrel Pelagodroma marina The white-faced storm-petrel bounces across the ocean surface with long, dangling legs, pushing off the water with both feet at once rather than the fluttering patter typical of most storm-petrels. Read the guide →
Birds LC White-faced Whistling Duck Dendrocygna viduata The white-faced whistling duck is one of the few duck species native to both South America and Africa, instantly recognizable by its bright white face against a dark body. Read the guide →
Birds LC White-Flanked Antwren Myrmotherula axillaris The white-flanked antwren rarely sits still, flicking its wings and tail almost constantly while gleaning insects from leaves in the forest understory. Read the guide →
Mammals EN White-Handed Gibbon Hylobates lar The white-handed gibbon is a small tree-dwelling ape that swings hand-over-hand through the canopy at 15 metres a swing and sings elaborate dawn duets with its lifelong partner. Read the guide →
Birds LC White-headed Petrel Pterodroma lessonii The white-headed petrel is a large gadfly petrel with an almost entirely white head and body set against dark wings, breeding in burrows scattered across remote subantarctic islands. Read the guide →
Birds LC White-headed Woodpecker Dryobates albolarvatus The white-headed woodpecker feeds heavily on pine seeds rather than insects, an unusually plant-based diet that ties this striking black-bodied bird closely to western pine forests. Read the guide →
Invertebrates LC White-Lined Sphinx Hyles lineata The white-lined sphinx hovers at flowers with such precise, hummingbird-like control that it is often mistaken for one, and its caterpillars can boom into desert migrations after heavy rain. Read the guide →
Mammals VU White-lipped Peccary Tayassu pecari The white-lipped peccary is a Vulnerable pig-like forest animal that travels in herds of hundreds, clacks its tusks as an alarm, and is a key food for jaguars and pumas. Read the guide →
Reptiles LC White-lipped Pit Viper Trimeresurus albolabris The white-lipped pit viper is a bright green tree viper of Southeast Asia that ambushes prey from branches, finds warm-blooded animals with heat-sensing pits, and is a common cause of snakebite. Read the guide →
Amphibians LC White-Lipped Tree Frog Litoria infrafrenata The white-lipped tree frog is the largest tree frog on Earth, identifiable at a glance by the crisp white stripe running along its lower jaw, and its deep, dog-like bark is unlike any other frog call. Read the guide →
Birds LC White-necked Puffbird Notharchus hyperrhynchus The white-necked puffbird perches motionless for long stretches, its bold black-and-white pattern breaking into sudden action to strike at passing insects and small prey. Read the guide →
Birds LC White-plumed Antbird Pithys albifrons The white-plumed antbird depends almost entirely on swarming army ants, following the ant columns to snatch insects the ants flush from hiding rather than eating the ants themselves. Read the guide →
Amphibians LC White-Spotted Slimy Salamander Plethodon cylindraceus The white-spotted slimy salamander was only recognised as its own species after the slimy salamander complex was split, one of more than a dozen nearly identical species hiding under one old name. Read the guide →
Invertebrates LC White-tailed Bumblebee Bombus lucorum The white-tailed bumblebee is a black bumblebee with lemon-yellow bands and a pure white tail that is almost impossible to separate in the field from its close buff-tailed relatives. Read the guide →
Mammals LC White-Tailed Deer Odocoileus virginianus The white-tailed deer flashes the bright white underside of its raised tail as an alarm signal, warning other deer of danger, and has become one of the most numerous large mammals in North America. Read the guide →
Mammals LC White-Tailed Jackrabbit Lepus townsendii The white-tailed jackrabbit turns almost entirely white for winter across the north, the largest hare in North America, built for open, wind-scoured plains and mountain grassland far colder than most. Read the guide →
Mammals LC White-Tailed Mongoose Ichneumia albicauda The white-tailed mongoose is the largest mongoose species in Africa, instantly recognisable by a bright white, bushy tail that trails conspicuously behind it at night. Read the guide →
Birds LC White-throated Caracara Phalcoboenus albogularis The white-throated caracara is a bold, ground-foraging bird of prey restricted to the southern Andes and Patagonia, scavenging carrion alongside live prey across harsh southern terrain. Read the guide →
Birds LC White-Throated Dipper Cinclus cinclus The white-throated dipper walks straight into fast mountain streams and along the riverbed underwater, the national bird of Norway and one of the only songbirds anywhere that swims for a living. Read the guide →
Birds LC White-throated Kingfisher Halcyon smyrnensis The white-throated kingfisher is one of the most commonly seen kingfishers across South Asia and the Middle East, just as likely spotted over a dry field hunting insects as beside a river. Read the guide →
Birds LC White-Throated Sparrow Zonotrichia albicollis The white-throated sparrow exists in two permanent color forms that almost always pair with the opposite form when mating, an unusual four-way mating system tied directly to a single chromosome. Read the guide →
Birds LC White-throated Treerunner Pygarrhichas albogularis The white-throated treerunner forages up tree trunks in a woodpecker-like manner, the sole member of its own genus and one of the more distinctive small birds of southern beech forest. Read the guide →
Birds LC White-tufted Grebe Rollandia rolland The white-tufted grebe displays a striking golden-white plume fanning out behind each eye during the breeding season, diving for small fish and invertebrates across South American lakes and lagoons. Read the guide →
Birds LC White-Winged Chough Corcorax melanorhamphos The white-winged chough lives in cooperative family groups so dependent on extra helpers that some groups resort to kidnapping fledglings from a neighboring group's nest. Read the guide →
Mammals LC White-Winged Vampire Bat Diaemus youngi The white-winged vampire bat feeds mainly on bird blood rather than mammal blood, setting it apart from its better-known relative, the common vampire bat. Read the guide →
Amphibians LC White's Tree Frog Litoria caerulea White's tree frog is a plump, placid blue-green frog with a permanent grin. Its skin secretes peptides being studied against bacteria, high blood pressure, and even HIV. Read the guide →
Fish LC Whiting Merlangius merlangus The whiting is a slim, silvery, barbel-less cod relative of the north-eastern Atlantic that hunts in shoals over sand and mud, and whose young shelter among the tentacles of jellyfish. Read the guide →
Birds EN Whooping Crane Grus americana The whooping crane, the tallest bird in North America, was down to 15 individuals in 1941 and survives today only through decades of captive breeding and aircraft-led migration. Read the guide →
Invertebrates LC Widow Skimmer Libellula luctuosa The widow skimmer carries bold black bands across the base of each wing, a pattern bold enough that a folk belief about males abandoning their mates gave the species its lasting name. Read the guide →
Mammals CR Wild Bactrian Camel Camelus ferus The wild Bactrian camel is a Critically Endangered, genetically distinct two-humped camel of the Gobi, which can drink brackish water saltier than seawater and survives in tiny numbers. Read the guide →
Mammals LC Wild Boar Sus scrofa The wild boar is the ancestor of the domestic pig, one of the most widespread mammals on Earth, and — as feral hogs — one of the most destructive invasive animals. Learn how it lives and spreads. Read the guide →
Birds LC Wild Turkey Meleagris gallopavo The wild turkey is a large, fast, wary forest bird that runs at 40 km/h, roosts in trees, and sees in near-360-degree colour. Domestic turkeys descend from it, bred in Mexico over 2,000 years ago. Read the guide →
Birds VU Wilkins's Bunting Nesospiza wilkinsi Wilkins's bunting has one of the largest bills relative to body size of any songbird, evolved specifically to crack open the tough seeds of a single tree species. Read the guide →
Birds LC Willet Tringa semipalmata The willet looks plain and unremarkable standing still, but the instant it takes flight, bold black-and-white wing stripes flash into view, transforming its appearance entirely. Read the guide →
Birds LC Willie Wagtail Rhipidura leucophrys The willie wagtail is a small, fearless black-and-white Australian bird that swings its long tail constantly and dive-bombs animals hundreds of times its size, including eagles, cats, and dogs. Read the guide →
Birds LC Willow Flycatcher Empidonax traillii The willow flycatcher looks almost identical to its sibling species the alder flycatcher, and the two are reliably told apart only by their completely different songs. Read the guide →
Birds LC Wilson's Storm-petrel Oceanites oceanicus Wilson's storm-petrel may be the most numerous seabird species on Earth, a sparrow-sized bird that breeds around Antarctica yet ranges across nearly every ocean during the rest of the year. Read the guide →
Birds LC Wilson's Warbler Cardellina pusilla Wilson's warbler is a tiny, active songbird with a neat black cap, and its western populations have declined so sharply that it is one of the most closely tracked warblers in bird-banding studies. Read the guide →
Fish LC Wobbegong Orectolobus maculatus The wobbegong is a flat, carpet-patterned shark that lies on the reef floor fringed with skin flaps, invisible until a fish or a careless foot comes within reach of its fast upward bite. Read the guide →
Fish NE Wolf Eel Anarrhichthys ocellatus The wolf eel is not a true eel but a long-bodied wolffish of the North Pacific. Pairs share a rocky den for life, crushing sea urchins and crabs with heavy jaws and molar teeth. Read the guide →
Invertebrates NE Wolf Spider Lycosidae Wolf spiders hunt on foot rather than in a web, running prey down and pouncing. Their big eyes throw back a green eyeshine in torchlight, and females carry the egg sac, then the young, on the body. Read the guide →
Mammals LC Wolverine Gulo gulo The wolverine is a 15-kilogram member of the weasel family that drives bears off carcasses and hunts prey in deep snow. Learn how it survives the far north and why warm winters threaten it. Read the guide →
Reptiles LC Woma Python Aspidites ramsayi The woma python hunts underground in burrows, using its blunt tail as a decoy that mimics its own head while the real business end strikes from the opposite direction. Read the guide →
Mammals LC Wombat Vombatus ursinus The wombat is a burrowing Australian marsupial with a backward-facing pouch, a bum made of armour, and — uniquely in the animal kingdom — cube-shaped droppings. Learn how and why. Read the guide →
Invertebrates NE Wonderpus Wunderpus photogenicus The wonderpus has a fixed pattern of reddish-brown and white markings unique to each individual, and mimics venomous sea snakes and lionfish by flattening its body and undulating its arms. Read the guide →
Birds LC Wood Duck Aix sponsa The wood duck is one of the most colourful waterfowl in North America, the male patterned in iridescent green, purple, and chestnut. It nests in tree cavities many metres up. Read the guide →
Amphibians LC Wood Frog Lithobates sylvaticus The wood frog survives being frozen solid every winter — heart stopped, most of its body water ice — then thaws back to life in spring. It ranges farther north than any other American frog. Read the guide →
Mammals LC Wood Mouse Apodemus sylvaticus The wood mouse is one of Europe's most common wild mice, a large-eyed, long-tailed night forager of woods, hedgerows, and fields that hoards seeds and feeds owls and foxes. Read the guide →
Birds LC Wood Pigeon Columba palumbus The wood pigeon is the largest and commonest pigeon in Britain and much of Europe, a plump grey farmland bird with a white neck patch that has left the woods to fill towns, gardens, and parks. Read the guide →
Birds LC Wood Thrush Hylocichla mustelina The wood thrush can sing two different notes simultaneously using both sides of its uniquely structured voice box, producing one of the most flute-like, layered songs of any North American bird. Read the guide →
Reptiles EN Wood Turtle Glyptemys insculpta The wood turtle has a shell that looks carved from wood, does well in maze and learning tests, and stomps the ground with its feet to bring earthworms to the surface. Read the guide →
Birds LC Woodcreeper Dendrocolaptidae A woodcreeper spirals up tree trunks probing bark for insects in a manner strikingly similar to the unrelated treecreeper, two unrelated bird families independently arriving at the same solution. Read the guide →
Amphibians LC Woodhouse's Toad Anaxyrus woodhousii Woodhouse's toad is a highly adaptable North American toad, tolerating everything from river floodplains to farmland, and it readily interbreeds with related toad species where ranges overlap. Read the guide →
Birds LC Woodland Kingfisher Halcyon senegalensis Despite its name suggesting a connection to water, the woodland kingfisher spends most of its life far from rivers and lakes, hunting insects and small reptiles across the African savanna instead. Read the guide →
Invertebrates NE Woodlouse Oniscidea A woodlouse is a land crustacean, a crab and shrimp relative that fully left the sea; it breathes through damp gill-like structures, eats dead leaves, and, in the pill bugs, rolls into a ball. Read the guide →
Birds NE Woodpecker Picidae A woodpecker is a bird that hammers into wood thousands of times a day, braced on a stiff tail, cushioned against the shock, and firing a spear-tipped tongue that wraps around its own skull. Read the guide →
Birds LC Woodswallow Artamus spp. The woodswallow is one of the only songbirds capable of true soaring flight, riding thermals on long triangular wings instead of flapping continuously like most perching birds. Read the guide →
Mammals VU Woolly Monkey Lagothrix lagotricha The woolly monkey carries one of the stockiest, most densely furred builds of any New World monkey, an unusually heavy-set primate for its treetop lifestyle. Read the guide →
Reptiles LC Worm Lizard Amphisbaenia A worm lizard is a burrowing reptile, neither snake nor true lizard, with a ringed pink body like a giant earthworm, a head built for digging, and the ability to move backwards as easily as forwards. Read the guide →
Birds LC Worm-Eating Warbler Helmitheros vermivorum The worm-eating warbler eats almost no worms at all, instead specialising in caterpillars hidden inside curled dead leaves, a foraging trick that gave the species a thoroughly misleading common name. Read the guide →
Fish NE Wrasse Labridae A wrasse is a colourful reef fish of one of the largest fish families, famous for the cleaner wrasse that eats parasites off other fish and for species that change sex from female to male. Read the guide →
Birds LC Wren Troglodytidae A wren is a tiny, round, brown bird with a cocked-up tail and a song astonishingly loud for its size, and the males of several species build a set of spare nests for the female to choose from. Read the guide →
Mammals LC Wrinkle-Faced Bat Centurio senex The wrinkle-faced bat has deeply folded facial skin, and males can pull a flap of skin up over the face like a mask for reasons still not fully understood. Read the guide →
Birds VU Wrybill Anarhynchus frontalis The wrybill is a small New Zealand plover and the only bird in the world with a bill that curves sideways, always to the right, which it uses to sweep under round riverbed stones for insect larvae. Read the guide →
Birds LC Wryneck Jynx torquilla The wryneck is a woodpecker that does not look or act like one, a small brown ground bird that eats ants and twists its neck like a snake when alarmed, which is how it got its name. Read the guide →
Invertebrates DD Wunderpus Octopus Wunderpus photogenicus The wunderpus octopus carries a bold reddish-brown and white striped pattern consistent enough for researchers to identify individuals by sight, often confused with its more famous mimicking relative. Read the guide →
Amphibians EW Wyoming Toad Anaxyrus baxteri The Wyoming toad is a small high-plains toad from one Wyoming valley, declared extinct in the wild in the 1990s and now kept alive by zoos that breed thousands of tadpoles a year for release. Read the guide →
Reptiles LC Yacare Caiman Caiman yacare The yacare caiman is a medium-sized crocodilian of the Pantanal and surrounding wetlands, where millions live, fish for piranha, and gather in dense groups in the shrinking pools of the dry season. Read the guide →
Mammals CR Yangtze Finless Porpoise Neophocaena asiaeorientalis The Yangtze finless porpoise is the only surviving cetacean in the Yangtze River since the baiji disappeared, a small, smiling-faced species now the sole focus of urgent conservation efforts. Read the guide →
Reptiles LC Yarrow's Spiny Lizard Sceloporus jarrovii Yarrow's spiny lizard gives birth to live young rather than laying eggs, an unusual trait for a spiny lizard suited to the cold mountain elevations it calls home. Read the guide →
Reptiles LC Yellow Anaconda Eunectes notaeus The yellow anaconda constricts prey rather than using venom, one of the largest snake species in South America, found gliding through wetlands across Paraguay, Bolivia, and northern Argentina. Read the guide →
Fish LC Yellow Bass Morone mississippiensis The yellow bass looks nearly identical to the white bass, but its dark side stripes are often broken and offset rather than running in straight, unbroken lines. Read the guide →
Fish LC Yellow Boxfish Ostracion cubicus The yellow boxfish is sealed inside a rigid box-shaped shell that can't bend to swim faster, and when stressed it releases a skin toxin strong enough to kill every other fish sharing its tank. Read the guide →
Fish LC Yellow Bullhead Ameiurus natalis The yellow bullhead tolerates warm, weedy, oxygen-poor water that would drive off most other fish, and pale whitish chin barbels help distinguish it from its darker-barbeled catfish relatives. Read the guide →
Fish LC Yellow Clown Goby Gobiodon okinawae The yellow clown goby is a tiny, bright yellow fish that lives among the branches of living coral, protected from predators by a toxic coating of skin mucus. Read the guide →
Invertebrates LC Yellow Jacket Vespula The yellow jacket scavenges human food at picnics unlike most other wasps, and its smooth, hairless body distinguishes it from the bees it is often mistaken for. Read the guide →
Mammals LC Yellow Mongoose Cynictis penicillata The yellow mongoose digs extensive burrow systems it sometimes shares with ground squirrels and meerkats, a sandy-coated southern African carnivore with a distinctive bushy white-tipped tail. Read the guide →
Fish LC Yellow Perch Perca flavescens The yellow perch is a golden, tiger-striped panfish of North American lakes, one of the most sought-after fish for eating and ice fishing, and a favourite prey of walleye, pike, and bass. Read the guide →
Birds VU Yellow Rail Coturnicops noveboracensis The yellow rail is one of the most elusive birds in North America, a tiny marsh dweller so reluctant to fly or be seen that many birders spend years searching before ever glimpsing one. Read the guide →
Fish LC Yellow Tang Zebrasoma flavescens The yellow tang carries a sharp, scalpel-like spine near the base of its tail that gives the whole surgeonfish family its name, used defensively against rivals and predators alike. Read the guide →
Birds LC Yellow Warbler Setophaga petechia The yellow warbler responds to a cowbird egg in its nest by building an entirely new nest floor right on top of it, sometimes stacking several buried layers in a single season. Read the guide →
Mammals VU Yellow-Bellied Glider Petaurus australis The yellow-bellied glider can glide more than 100 metres between trees and carves distinctive V-shaped notches into bark to feed on the sap that pools there. Read the guide →
Mammals LC Yellow-bellied Marmot Marmota flaviventris The yellow-bellied marmot sunbathes on rocky slopes of western North America, whistles an alarm at danger, and hibernates for most of the year in a mountain burrow. Read the guide →
Birds LC Yellow-bellied Sapsucker Sphyrapicus varius The yellow-bellied sapsucker drills neat rows of small holes into tree bark to drink the sap that wells up, a food source shared with insects and other birds drawn to the same sugary wells. Read the guide →
Reptiles LC Yellow-bellied Sea Snake Hydrophis platurus The yellow-bellied sea snake is the most widespread snake on Earth and the only one that lives its whole life in open ocean, drifting at current lines to ambush fish. It cannot slither on land. Read the guide →
Amphibians LC Yellow-bellied Toad Bombina variegata The yellow-bellied toad flips onto its back and arches into a warning pose when threatened, flashing a vivid black-and-yellow belly usually hidden from view. Read the guide →
Birds LC Yellow-billed Pintail Anas georgica The yellow-billed pintail ranges from high Andean lakes to sub-Antarctic islands, identified by a bright yellow bill against mottled brown plumage. Read the guide →
Birds LC Yellow-billed Teal Anas flavirostris The yellow-billed teal ranges from high Andean lakes in Colombia all the way south to Tierra del Fuego, one of the broadest latitudinal ranges of any South American duck. Read the guide →
Birds LC Yellow-Crowned Night-Heron Nyctanassa violacea The yellow-crowned night-heron specializes on crustaceans, using a heavy, blunt bill built for crushing crayfish and crab shells rather than the slender spear typical of most herons. Read the guide →
Birds EN Yellow-eyed Penguin Megadyptes antipodes The yellow-eyed penguin is one of the rarest penguin species in the world, nesting alone in dense coastal forest rather than in the crowded colonies typical of most other penguins. Read the guide →
Mammals VU Yellow-Footed Rock-Wallaby Petrogale xanthopus The yellow-footed rock-wallaby carries some of the boldest markings of any macropod, banded orange legs and tail standing out against the arid outcrops it calls home. Read the guide →
Birds EN Yellow-Headed Amazon Amazona oratrix The yellow-headed amazon is renowned as one of the most talented talking parrots in the world, a reputation for mimicry that has driven relentless trapping and pushed the species toward extinction. Read the guide →
Birds LC Yellow-Rumped Warbler Setophaga coronata The yellow-rumped warbler can digest waxy bayberry and wax myrtle fruit that most other warblers cannot process, letting it winter farther north than almost any other North American warbler species. Read the guide →
Mammals CR Yellow-tailed Woolly Monkey Lagothrix flavicauda The yellow-tailed woolly monkey is a rare, shaggy-coated monkey found only in the cloud forests of the Peruvian Andes, rediscovered in the 1970s and now Critically Endangered. Read the guide →
Mammals LC Yellow-winged Bat Lavia frons The yellow-winged bat is a bright yellow-orange African bat that roosts in the open on acacia branches by day and hunts insects from a perch like a flycatcher. Read the guide →
Fish NT Yellowfin Grouper Mycteroperca venenosa The yellowfin grouper can carry a hidden risk in its flesh despite looking like any other reef fish, one of several groupers capable of accumulating ciguatera toxin from its reef diet. Read the guide →
Fish NT Yellowfin Tuna Thunnus albacares The yellowfin tuna is a fast, warm-water predator with striking yellow finlets, capable of sustained swimming speeds that make it one of the most commercially important fish in the world's oceans. Read the guide →
Fish LC Yellowhead Jawfish Opistognathus aurifrons The yellowhead jawfish digs and lines its own burrow in the sand, hovering tail-down above it, and the male carries the eggs in his mouth until they hatch. Read the guide →
Invertebrates NE Yeti Crab Kiwa hirsuta The yeti crab lives around scalding deep-sea hydrothermal vents, its claws covered in dense bristles it uses to farm colonies of bacteria for food, waving them in the current to help them grow. Read the guide →
Amphibians LC Yonahlossee Salamander Plethodon yonahlossee The Yonahlossee salamander occupies high-elevation forest in the southern Appalachians, a large, boldly patterned lungless salamander named after the mountain pass where it was first described. Read the guide →
Amphibians EN Yosemite Toad Anaxyrus canorus The Yosemite toad is a high-elevation Sierra Nevada specialist whose entire world is a scattering of wet mountain meadows above 6,000 feet, now shrinking under a warming climate. Read the guide →
Fish LC Yoyo Loach Botia almorhae The yoyo loach carries a bold, zigzagging body pattern that some keepers read as a string of "Y" and "O" letters, spelling out the toy that gave the species its playful common name. Read the guide →
Fish LC Zander Sander lucioperca The zander, or pikeperch, is a large, pale-eyed predator of murky European lakes and rivers with fangs like a pike and the spiny fin of a perch, prized as food and widely introduced. Read the guide →
Mammals EN Zanzibar Red Colobus Piliocolobus kirkii The Zanzibar red colobus is an Endangered monkey found only on Unguja Island, which eats charcoal to settle its stomach and is threatened by forest loss and by traffic on island roads. Read the guide →
Birds CR Zapata Rail Cyanolimnas cerverai The Zapata rail survives only within Cuba's Zapata Swamp, a nearly flightless bird so rarely encountered that decades sometimes pass between confirmed sightings by researchers. Read the guide →
Invertebrates NE Zebra Isopod Armadillidium maculatum The zebra isopod carries bold black and white banding across its body, a strikingly patterned terrestrial isopod that can roll into a tight ball when threatened like other pillbugs. Read the guide →
Invertebrates LC Zebra Longwing Heliconius charithonia The zebra longwing is the only North American butterfly known to feed on pollen as an adult, a habit that extends its lifespan to several months, far longer than most other butterflies survive. Read the guide →
Fish LC Zebra Mbuna Maylandia zebra The zebra mbuna was one of the first Lake Malawi rock cichlids described, and its natural colour morphs vary so widely that different rocky outcrops can look like different species. Read the guide →
Invertebrates NE Zebra Mussel Dreissena polymorpha The zebra mussel attaches to hard surfaces using sticky threads most freshwater mussels lack, and a single lake population can filter enough water to reshape the whole ecosystem beneath it. Read the guide →
Fish EN Zebra Shark Stegostoma tigrinum The zebra shark hatches striped like its name but grows up spotted like a leopard. Docile enough to be hand-fed by divers, it can store sperm for years before fertilising eggs. Read the guide →
Invertebrates NE Zebra Spider Salticus scenicus The zebra spider is a tiny black-and-white striped jumping spider that stalks prey across sunny walls and leaps on it, secured by a silk safety line and guided by large, sharp eyes. Read the guide →
Invertebrates LC Zebra Swallowtail Protographium marcellus The zebra swallowtail's caterpillar can develop only on pawpaw trees, tying this entire striking, boldly striped butterfly species to the presence of a single, patchily distributed plant. Read the guide →
Reptiles LC Zebra-tailed Lizard Callisaurus draconoides The zebra-tailed lizard is one of the fastest lizards in North America, sprinting across open desert flats and curling its bold, black-and-white banded tail up over its back as a warning signal. Read the guide →
Fish LC Zebrafish Danio rerio A zebrafish is a small striped aquarium minnow that has become one of biology's top laboratory animals because its see-through embryos develop outside the body and it regrows damaged organs. Read the guide →
Amphibians LC Zigzag Salamander Plethodon dorsalis The zigzag salamander is a small, lungless woodland salamander named for the jagged stripe running down its back, and it breathes entirely through its moist skin and the lining of its mouth. Read the guide →
Invertebrates NE Zombie Worm Osedax The zombie worm has no mouth, gut, or eyes, and lives by boring into the bones of dead whales on the deep-sea floor, dissolving them with acid and digesting them with the help of bacteria. Read the guide →