Pseudagkistrodon

Pseudagkistrodon is a small genus in the family Colubridae, the largest snake family in the world and the one that holds most of the planet's nonvenomous and mildly venomous species. The genus is best known from the False Habu, Pseudagkistrodon rudis, a terrestrial snake of eastern Asia. The name itself tells the story: it combines the Greek for false with Agkistrodon, a genus of true pit vipers, because this colubrid resembles those dangerous snakes in build and patterning. That resemblance is the defining trait of the genus, a case of a harmless snake looking like a feared one. Some authorities place this species within or close to the genus Rhabdophis, which reflects how taxonomy in this part of the colubrid tree continues to shift.

Members are found in parts of eastern and southeastern Asia, where they live in damp forest floor, leaf litter, and the edges of streams and wet meadows in cooler upland settings. In general terms they are stout for their length, with a triangular or arrow shaped head, keeled scales that give a rough textured look, and a brown to reddish ground color broken by darker blotches. That viper like profile is exactly what fools predators and people, but the underlying body is built like a typical ground dwelling colubrid rather than a pit viper. There is no heat sensing facial pit, which is one of the clearest separations from the true habu vipers it imitates.

Snakes in this genus are not front fanged vipers and are regarded as harmless to humans, with no medically significant venom apparatus of the kind pit vipers carry. Like many colubrids they feed mostly on cold blooded prey such as frogs and other amphibians, hunting along the wet ground where those animals gather, and they reproduce by laying eggs as is typical for the family. Because the False Habu is so easily mistaken for a genuinely dangerous pit viper, identification in the field should never be treated casually. Do not handle any wild snake you cannot positively identify, and if a venomous bite is ever suspected, skip first aid experiments and contact emergency services or, in the United States, Poison Control at 1-800-222-1222 right away.