Also, the first lower labial scale on each side is transversely divided to form a pair of anterior chin shields.

[2] Dwelling in brush covered hillsides, a favored habitat is the small caves and clefts of reddish sandstone mesas.

It prefers the dense chaparral country of the foothills, cactus patches, and boulders covered with brush, from sea level to 1,500 m in altitude.

Brown (1973) lists an average venom yield of 364 mg (dried) and LD50 values of 4.0, 3.7 mg/kg IV, 6.0, 7.0, 6.7 mg/kg IP and 21.2 mg/kg SC for toxicity.

[18] However, Norris (2004) warned this species has a relatively large venom yield containing high levels of proteolytic enzymes, especially in the adults.

A publication he mentions by Rael et al. (1986) showed it contains at least three proteolytic hemorrhagins that degrade fibrinogen and cause myonecrosis, but no Mojave toxin.

[19] Bite symptoms include massive tissue swelling, pain, ecchymosis, hemorrhagic blebs, and necrosis.

[20] Not enough genetic and morphological diversity exists between C. exsul from Cedros Island and C. ruber from the mainland to warrant the recognition of both species.

In response, Smith et al. (1998) petitioned the ICZN to validate ruber over exsul in the interest of nomenclatural stability.