The Sonoran Desert is home to five rattlesnakes species under the genus Crotalus: western diamondback, sidewinder, blacktail, Mojave and tiger. All six species have rattles attached to the end of their tails, which they rattle when threatened or alarmed. These rattlesnakes are called pit vipers, due to the facial pits between their eyes and nostrils. A rattlesnake's facial pit has heat sensors, allowing it to detect warm-blooded prey in the dark. Each Sonoran Desert rattlesnake has a triangular-shaped head and fangs for injecting venom into its prey.
Rosy boas (Lichanura trivirgata) are nonvenomous snakes found in western Arizona and southeastern California. This snake receives its "rosy" moniker from the light red coloration on its scales. This snake may live in desert scrublands and high elevations of over 5,600 feet. Rosy boas are the only snake in Arizona in the Boidae snake family. These snakes are usually nocturnal but will come out into the open on overcast days. The rosy boa has two subspecies in Arizona: the Mexican rosy boa (Lichanura trivirgata trivirgata) and desert rosy boa (Lichanura trivirgata gracia).
Two shovelnose snakes dwell in the Sonoran Desert: the Sonoran shovelnose (Chionactis palarostris) and western shovelnose (Chionactis occipitalis). Both shovelnose snakes have flat-shaped noses and resemble shovels. The Sonoran shovelnose snake, or the Organ-Pipe shovelnose, is only found in the Organ-Pipe Cactus National Monument region of Arizona. This snake resembles the venomous Sonoran coral snake, which is also a native of Arizona. However, shovelnose snakes are not venomous. The western shovelnose snake's range covers Arizona and northern Mexico.
Whip snakes are in the Masticophis genus of snakes. The Sonoran Desert has two Masticophis snakes, the coachwhip and Sonoran whipsnake. The coachwhip (Masticophis flagellum) is also known as the red racer. Whip snakes have slender bodies and sharp whiplike tails. Sonoran whipsnakes (Masticophis bilineatus) are primarily found in Mexico and live at elevations of up to 6,000 feet; some Sonoran whipsnakes live in southern Arizona. The longer of the two whipsnakes, the coachwhip, reaches lengths of 8 to 9 feet; these snakes live throughout the Sonoran Desert in Arizona, northern Mexico and California.