Caiman Lizard

Almost entirely snails. The northern caiman lizard is one of the few lizards that is a true dietary specialist on hard-shelled prey. It hunts along the bottom of slow, weedy blackwater rivers and flooded forest for aquatic snails, particularly large apple snails, along with freshwater bivalves and crayfish. It grasps a snail, carries it to the surface or a perch, positions it against the broad crushing teeth at the back of its jaws, and bites down with enough force to shatter the shell. It then uses its fleshy tongue and the roof of its mouth to work the soft body free and lets the shell fragments fall away. Its whole skull is built around this — reduced sharp front teeth, enormous rounded rear teeth, and oversized jaw-closing muscles.

No. It is a lizard, a member of the tegu and whiptail family (Teiidae), and its resemblance to a caiman is convergent evolution driven by a shared semi-aquatic lifestyle. Both have raised, bony scales forming a ridged, armoured back; both have a tall, flattened, keeled tail used to scull through water; and both bask at the water's edge and dive when alarmed. Looking like a small crocodilian may also deter some predators. But the caiman lizard has no bony scutes on its belly, lays fewer, larger eggs, and of course has the specialised snail-crushing dentition that no caiman has.

Several ways. Its tail is flattened side-to-side and topped with a double row of raised scales, forming a paddle that propels it with side-to-side undulations like a crocodile or a sea snake. Its nostrils are set high on the snout so it can breathe with most of its head submerged, and it has a transparent lower eyelid that acts like a swimming goggle. It can hold its breath and remain underwater for extended periods while foraging on the bottom. On land it is a capable climber and basks on branches overhanging the water, from which it can drop straight in to escape. It sleeps in burrows or dense vegetation on the bank.

They are kept, and captive-bred animals are increasingly available, but they are an advanced species and a significant commitment. An adult needs an enclosure several metres long with a large, deep, heated, filtered pool it can fully submerge in, plus a warm dry basking area, strong UVB lighting, and humidity around 70 to 80 percent. Feeding is the biggest challenge — they do best on a diet built around snails (canned or farmed), supplemented with other shellfish and some whole prey, which is expensive and hard to source in quantity. They can be nippy and are powerful for their size. Wild-caught imports often arrive stressed and parasitised, so captive-bred is strongly preferred.