Plains Hognose Snake

The western hognose snake (Heterodon nasicus) is a species of snake in the family Colubridae. The species is endemic to North America. There are three subspecies that are recognized as being valid, including the nominotypical subspecies.

Etymology

The specific name, nasicus, is derived from the Latin nasus ("nose"), a reference to the snake's upturned snout.

The dusky hognose's subspecific name, gloydi, is in honor of American herpetologist Howard K. Gloyd (1902–1978).

The Mexican hognose's subspecific (or specific) name, kennerlyi, is in honor of American naturalist Caleb Burwell Rowan Kennerly.

Common names

Common names for Heterodon nasicus include blow snake, bluffer, plains hognose snake, prairie hognose snake, spoonbill snake, spreadhead snake, Texas hognose snake, Texas rooter, and western hognose snake.

Taxonomy

Some authors elevate the subspecies Heterodon nasicus kennerlyi, also known as the Mexican hognose snake, to species level. Those same authors have subsumed H. n. gloydi into H. nasicus so that there are only two species (H. nasicus and H. kennerlyi) and no subspecies.

Description

The western hognose snake is a relatively small, stout-bodied snake. Its color and pattern is highly variable between subspecies, although most specimens appear much like rattlesnakes to the untrained eye, which appears to be Batesian mimicry. Males are considerably smaller than females, with adults rarely exceeding a total length (tail included) of 40–50 cm (15–20 inches). This snake gets its common name, "hognose", from the modified rostral (nose) scale that is formed in an upturned manner, providing a very "hog-like" look. Additionally, this adaptation makes this snake an adept burrower.

The species is not dangerous to humans, as no deaths or systemic effects from the extremely rare bite from this rear-fanged snake have been recorded. Although bites may uncommonly be medically significant, the species is not regarded as venomous. In the capture and incapacitation of prey the modified saliva is released from Duvernoy's Glands and travels down a groove in the snake's fang.

In captivity, the species has been bred into more than 50 different "designer" color morphs.

Distribution and habitat

The western hognose snake occurs from southern Canada throughout the United States to northern Mexico. It frequents areas with sandy or gravelly soils, including prairies, river floodplains, scrub and grasslands, semi-deserts, and some semiagricultural areas. It has been found at elevations of up to 2,500 m (8,200 feet).

Ecology

Behavior

The western hognose snake is primarily diurnal. It is typically a docile snake (though known to be highly defensive in some individuals). If threatened (or perceiving a threat), it may flatten its neck (much like a cobra), hiss, and make 'mock' or 'bluff' strikes if harassed, which are strikes made at an intruder but with the snakes' mouth closed. Subsequently, even when further harassed, western hognose snakes virtually never bite as a self defense mechanism, but will instead usually resort to playing dead.