Hognose Snake

The hognose snake is a type of colubrid snake characterized by an upturned snout. They are notorious for playing dead when threatened. The hognose snakes consist of three distantly related genera that are artificially grouped together by the "hognose" common name: Heterodon which are predominantly found in United States and northern Mexico. Leioheterodon the Madagascar hognose snakes, and Lystrophis the South American or tri-colored hognose snakes.

Hognose snakes' most distinguishing characteristic is their upturned snout, which aids in digging in sandy soils by using a sweeping, side to side motion. They also like to burrow in masses of humus.

Hognose snakes are extremely variable in color and pattern. H. nasicus and H. kennerlyi tend to be sandy colored with black and white markings, while H. platirhinos varies from reds, greens, oranges, browns, to melanistic (i.e. black) depending on locality. They are sometimes blotched and sometimes solid-colored. L. geayi is a brown or tan colored snake with dark speckling on it. L. madagascariensis is typically green and yellow with a black checkerboard pattern along its back. L. modestus is normally a gold-brown color. The species in the genus Lystrophis are referred to as tri-color hognose snakes and sometimes as false coral snakes because they display alternating bands of red, white, and black.

Leioheterodon are the largest of the hognose snakes, capable of reaching lengths of 1.8 m. H. platirhynos gets slightly larger than other species of the genus, reaching lengths of 80 cm, where other species in the genus as well as Lystrophis species usually average around 65 cm at adult size.

Hognose snakes (Heterodon) are rear-fanged and technically not venomous, but the saliva they excrete is considered toxic to prey but not considered to be dangerous to humans and they will never bite in defense (as the only way to get bitten by a hognose snake is to smell like their prey). There has been some debate whether or not hognose are venomous, but there is evidence that their saliva has some toxicity to smaller prey items, such as toads and frogs. The fangs have been referred to as just "enlarged teeth", but they are genuine fangs that are used for prey restraint. Despite the common belief, there is no evidence to support the fangs being used for "toad popping". Under this belief, the toads inflate their lungs to make swallowing difficult, but the fangs would penetrate the lungs and deflate them. However, whole toads with intact lungs are commonly regurgitated by recently captured hognoses.

The coloration of this essentially spotted snake is extremely variable,with color phases ranging from yellow and brown to black and gray. The most reliable field work is the turned-up, hoglike snout, which is used for digging out the toads that are its primary food.