Family: Viperidae, Pit Vipers view all from this family
Description 23-52" (58.4-132.1 cm). Pattern and color vary greatly; generally has a sandy, speckled appearance. Back marked with muted crossbands or hexagonal- to diamond-shaped blotches formed by small cluster of dots. Large scale above eye pitted, creased, or rough-edged; or rostral scale separated from preanals by row of tiny scales. Scales keeled, in 23-27 rows.
Warning Rattlesnakes, Copperheads, and Cottonmouths belong to a group of snakes known as pit vipers. These dangerous snakes have a heat-sensitive sensory organ on each side of the head that enables them to locate warm-blooded prey and strike accurately, even in the dark. The curved, hollow fangs are normally folded back along the jaw. When a pit viper strikes, the fangs rapidly swing forward and fill with venom as the mouth opens. The venom is a complex mixture of proteins that acts primarily on a victim's blood tissue. If you hear a rattlesnake shaking its rattle, back away. The snake is issuing a warning, and if the warning is ignored it may bite. There are many factors (temperature being the most important) that determine how a snake will react when confronted by a human. Venomous snakes should always be observed from a safe distance. Pit vipers are never safe to handle. Even dead ones can retain some neurological reflexes, and "road kills" have been known to bite. How to avoid and treat snakebites
Subspecies Southwestern (C. m. pyrrhus), rostral scale separated from prenasals by small scales; sw. Utah, w. Arizona, extreme s. tip of Nevada, s. California.
Panamint (C. m. stephensi), large scale above eye pitted, creased, or roughly edged; s. Nevada and adjacent California.
Breeding July to August, female gives birth to 2-11 young, 8-12" (20-30 cm) long.
Habitat Prefers rugged rocky terrain, rock outcrops, deep canyons, talus, chaparral amid rock piles and boulders, rocky foothills; sea level to 8,000' (2,450 m).
Range Extreme sw. Utah, s. Nevada and s. California south into nw. Sonora and throughout Baja California.
Discussion Active during the day in spring and fall, at night in summer. Eats ground squirrels, kangaroo rats, white-footed mice, birds, and lizards. Record longevity exceeds 16 years.
