Amphibians

Rain Frog

Brevicipitidae · also called black rain frog, short-headed frog

Not Evaluated insectivore Temperate grassland Desert Temperate forest

The rain frog looks permanently furious, and the internet loves it for that. In reality it is a placid little African balloon of a frog that lives underground, cannot jump or swim, gets glued to its much larger mate for a fortnight, and never produces a tadpole. The scowl is just the shape of its mouth.

Overview

Rain frogs are the family Brevicipitidae, around 35 species, in eastern and southern Africa. They have a squat, rounded, inflated-looking body, a tiny downturned mouth that reads as a frown, and very short stubby legs, so they cannot leap, climb, or swim — they waddle. They are insectivores, eating termites, ants, and beetles in the soil and litter.

An underground life

A rain frog digs tail-first into loose or sandy soil with spade-tipped hind feet and spends most of its life buried, surfacing mainly on humid nights and after rain. The male calls from a burrow mouth with a squeak or chirp, not a croak.

Glued mates, no tadpoles

The male is much smaller than the female and cannot grip her broad body, so she secretes a skin glue that cements the pair together for days to two weeks until she lays. The eggs are large and yolky, laid in an underground chamber, and develop directly into froglets — no free-swimming tadpole — which frees rain frogs from needing any standing water.

Status

Rain frogs as a family are Not Evaluated. Several are common, but many are narrow-range specialists of single mountains or forest patches in South Africa, Tanzania, and Kenya, and some, squeezed by farming, plantations, and urban spread, are threatened or Critically Endangered.

Rain Frog: common questions

Is the rain frog really angry?

No. The scowling, frowning look of a rain frog, and of the black rain frog especially, is simply the fixed shape of its small, downturned mouth and its rounded, wrinkled face, and it has nothing to do with the animal's mood. Rain frogs are actually rather placid and slow-moving. When one does feel threatened it responds by inflating its body like a balloon to look bigger and harder to swallow or pull from a burrow, and by giving a high squeaky cry, which viewers found endearing and which helped the black rain frog become an internet favourite. The permanent frown is just anatomy.

Why can't a rain frog jump or swim?

Its body has evolved for a burrowing life, and the trade-offs rule out both. A rain frog has a heavy, rounded body and very short, weak legs with little of the long lever-like foot and powerful thigh that a jumping frog uses, so it cannot generate a leap, and its bulk and stubby limbs also make it a poor swimmer that can drown in deep water. What it can do well is dig, shuffling backward into sandy soil with spade-tipped hind feet. It gets around on the surface by a slow crawl or waddle. This is a common pattern in frogs that have specialised for living underground rather than around water.

How do rain frogs breed without water?

They have done away with the aquatic stage of the frog life cycle. Instead of laying many small eggs in a pond that hatch into swimming tadpoles, a female rain frog lays a small number of large eggs, well stocked with yolk, in a moist chamber underground. The tadpole stage happens inside the egg, fed by the yolk, and what emerges is a miniature adult frog. This direct development means rain frogs never need standing water at all, which is why they can live in dry sandy shrubland and desert margins where pond-breeding frogs cannot survive.

Why does the male stick to the female during mating?

It is a practical solution to a size problem. In rain frogs the female is much larger and rounder than the male, and the male's arms are far too short to reach around her body and grip in the usual frog mating hold, called amplexus. Without a grip he would be dislodged before the eggs are laid. To keep the pair together, the female produces a strong, quick-setting glue from glands in her skin that bonds the male to her back, and the two remain cemented together, sometimes for a couple of weeks, moving about and burrowing as one until she lays. The glue then loosens and the male detaches.

Sources & further reading

Written by HideShark Editorial Team · reviewed by HideShark Science Desk. Published September 10, 2026. Last updated September 10, 2026.

Quick facts

Scientific name: Brevicipitidae
Diet: Small soil and surface invertebrates such as termites, ants, beetles, and their larvae, plus mites and small worms, hunted in and just below the leaf litter and soil rather than by the ambush-and-flick method of most frogs
Built like a balloon, not a frog: Rain frogs have a squat, rounded, inflated-looking body, a tiny head with an almost fixed downturned mouth that gives a permanently grumpy expression, and very short stubby legs, so they cannot leap, climb, or swim and instead walk or waddle slowly over the ground
They dig in backward: Using hardened spade-like tubercles on the hind feet, a rain frog shuffles tail-first straight down into loose or sandy soil, and it spends most of its life buried, coming to the surface mainly on humid nights and after rain to feed and breed
The mate is glued on: A male rain frog is far smaller than the female and cannot reach around her broad body to hold on during mating, so the female secretes a sticky glue from her skin that cements the pair together back to belly for several days to a couple of weeks until the eggs are laid
No tadpole stage: Rain frogs lay a small clutch of large yolk-rich eggs in an underground chamber, and the embryos develop directly into fully formed tiny froglets inside the egg, skipping the free-swimming tadpole entirely, which frees the frogs from any need for standing water and suits their dry, sandy habitats
The internet's grumpiest frog: The black rain frog of South Africa's Cape mountains, a dark, wrinkled, scowling species that puffs itself up and gives a high squeaky cry when threatened, became a viral image in the 2010s as the world's angriest or grumpiest frog, though the expression is just the fixed shape of its mouth
A voice that squeaks and chirps: Male rain frogs call from the mouth of a burrow with a short chirp, whistle, or squeak rather than the croak or trill of most frogs, and a startled or handled rain frog inflates its body and produces a sharp squeaking protest sound
Range: Sub-Saharan Africa, mainly the eastern and southern parts of the continent, from the Cape region of South Africa north through the mountains of Malawi, Tanzania, and Kenya, in fynbos and other shrubland, grassland, coastal dune scrub, farmland, gardens, and montane and lowland forest, always where the soil is loose or sandy enough to burrow into.
Conservation status: Not Evaluated ≈ Not assessed as a family of around 35 species, and several rain frogs are common within their ranges, but a number are narrow-range specialists confined to single mountains, forest patches, or coastal lowlands in South Africa, the Eastern Arc mountains of Tanzania, and elsewhere in eastern and southern Africa, and some of these, hit by farming, plantation forestry, and urban spread, are listed as threatened or Critically Endangered in the wild