Viperidae
Crotalus willardi, ridge-nosed rattlesnake
The ridge-nosed rattlesnake is a small montane rattlesnake, which has 3 subspecies in our region. Obscurus has a very small range living in the Sierra San Luis, Animas and Peloncillo Mountains. Silus lives in the southern Sky Islands and parts of the Sierra Madre. Willardi occurs in the Sky Islands of northern Sonora and southern Arizona.
