DESCRIPTION: L=up to just over 2' (61cm). Overall sandy brown with dark blotches down the back separated by light-colored bands. Horn-like structures above each eye are diagnostic.
NATURAL HISTORY: Venomous. The toxin is extremely painful and medical attention should be sought immediately (the bite is potentially fatal -- when bitten, call the Arizona Poison and Drug Information Center at 626-6016 in Tucson and 1-800-362-0101 elsewhere in Arizona). See also section on Venomous Animals.

Carnivorous, feeding mostly on rodents, but also eating other small animals. Sidewinder vary their activity time depending on the temperature (diurnal when colder, crepuscular and nocturnal when hotter). In colder portions of its range, Sidewinders will hibernate singly in rodent or tortoise burrows. Found in sandy desert areas. Lowe et al. (1986) state that "this is the only desert endemic [occurring only in the desert] species among the venomous reptiles in North America, and one of the very few desert-endemic vertebrates on the continent." They get their name from the way they move across the hot sand. The track is a series of diagonal lines in the sand, as the snake moves sideways, hold all but two points of its body off the sand (to reduce heat gain from the sand). Gives birth to live, venomous young. See Rattlesnake Facts for more information.