Crotaphytus bicinctores
(Mojave Black-collared Lizard)

General Description:
Mojave Black-collared Lizards are large headed, big bodied lizards with two distinct black collars separated by a white band.  The dorsal coloration can range from a light tan to gray or reddish-brown, and is marked by fuzzy crossbands that are a lighter shade of tan or brown.  There are usually light spots or speckles on the dorsal ground color.   These light colored spots get more profuse on the limbs and tail, and begin merging to form a reticulated pattern.  The ventral coloration is a light cream and is marked by charcoal or bluish-black colored patches on the groin and throat of males.  In general, adult males tend to be more vividly colored, while females and juveniles have a lighter, more washed-out appearance.

Mojave Black-collared Lizards are one of the largest lizard species found in Idaho, with snout to vent lengths (svl) reaching 109 mm (4.3 in.) and total lengths reaching around 330 mm (13 in.) (Storm and Leonard 1995).  The tail (which can add six or seven inches to the total length) is slightly compressed on the sides.  This aids in distinguishing between Mojave Black-collared Lizards and Longnose Leopard Lizard, as the later have more rounded tails.  Mojave Black-collared Lizards lack the ability to lose their tail along fracture planes, while Longnose Leopard Lizards can lose their tail (Pough et al. 1998).

Little is known about the details of Mojave Black-collared Lizard reproduction in the Northwest.  However, based on information from more southern populations, it is likely that they mate in the spring, and lay a clutch of 3 to 8 eggs (Nussbaum et al. 1983).  The neonates are similar in form and coloration to adults (see above regarding coloration).

Habitat:
Mojave Black-collared Lizards are associated with arid habitats, and a critical component of the habitat appears to be the presence of rocks and boulders.  These lizards aren't adept at climbing, so the boulders are generally not too large.  The surrounding vegetation is generally sparse (Storm and Leonard 1995).

Idaho Distribution:
Mojave Black-collared Lizards are found in southwestern portion of the state, along the Snake River Plain and surrounding Owyhee foothills.  From northeastern California, southeastern Oregon, and adjacent parts of Idaho, Nevada, and western Utah, south into Arizona and southeastern California.

Diet:
Feeds mainly on insects and other lizards, but is also known to eat small amounts of flowers and leaves.

Ecology:
Hibernates/aestivates. Inactive during cold winter weather; duration of inactive period varies with local climate.

Reproduction:
Reproduction information for northwestern portions of range is lacking. In Arizona, eggs are laid in June or July, and hatch in October. In other areas in range, members of the same genus lay 1-2 clutches of 3-8 eggs/yr. In southern populations, some females mature after 1 yr.

Conservation:

Status:	Unprotected nongame species
Global Rank:	G5
State Rank:	S2

Important State Reference:
Diller, L.V. and D.R. Johnson.1982. Ecology of reptiles in the Snake River Birds of Prey Area. USDI Bur. Land Manage. Snake River Birds of Prey Research Project, Boise. 107pp.