Crotalus oreganus cerberus - Arizona Black Rattlesnake
According to Wright and Wright (1957), adults grow to an average length of 78-109 cm. Klauber (1997) reports the maximum length to be less at 1,032 mm, with the smallest gravid female measuring 701 mm.
The color pattern consists of a dark grayish, brownish black, reddish brown, or blackish ground color, overlaid with a dorsal pattern of blotches that are rectangular anteriorly, becoming subhexagonal posteriorly, eventually becoming crossbands just before the tail. However, specimens also may be a uniform dark color without any clear dorsal pattern, or the dorsal blotches may be even darker and bordered with white, cream, or yellow transverse rows of scales, or the color pattern may be quite pale with a significant amount of yellow mixed in. A postocular stripe is evident in lightly colored specimens, but not so much in darker ones.
Arizona black rattlesnake, black rattlesnake, black diamond rattlesnake, brown rattlesnake, Cerberus rattlesnake, mountain diamond-back.
Found in the United States, in Arizona from the Hualapai Mountains and Cottonwood Cliffs in the northwest of the state, southeast to the Santa Catalina, Rincon, Pinaleno and Blue Mountains. Also found at Steeple Rock, in extreme western New Mexico. The type locality given is "San Francisco Mountains" (Coconino County, Arizona, USA).