Colorado Desert Fringe-toed Lizard

Description:

Appearance A medium-sized, flat-bodied, smooth-skinned lizard that inhabits areas of loose sand. Color is white, with a contrasting pattern of broken black lengthwise lines and round, eye-like spots. The color and pattern create a successful camouflage which allows a lizard to blend into its sandy habitat. The underside is pale with black bars on the underside of the tail. The sides of the belly have an orange or pinkish stripe, which intensifies during the breeding season. Males have a conspicuous black bar or spot on the sides of the belly, dark diagonal lines on the throat, and enlarged postanal scales. Behavior and Natural History Diurnal. Adapted to living in areas with fine windblown sand. A fringe of scales on the sides of the toes help this lizard run quickly over fine sand, preventing them from sinking, similar to the effect of wearing snowshoes. Scales are granular and very small, which helps a lizard bury itself quickly in fine sand. A countersunk lower jaw, eyelids that overlap, flaps over the ears, and nostrils and nasal passages which work like valves, all prevent sand from getting into a lizard's orifices and lungs. Takes cover in the sand to avoid extreme temperatures. Commonly sleeps in the sand under a bush at night. The parietal eye, an eye-like structure on top of the head, is thought to help this lizard monitor the amount of solar radiation it receives to help it avoid too much or too little heat. On waking in the morning, a lizard often basks with just the head above the sand until its body temperature warms sufficiently to allow it to unbury the entire body and continue basking or begin activity. Goes underground in the sand or in a burrow in the fall, and emerges in late winter. Young lizards may go under later and emerge earlier or even remain active all year. When scared, this lizard will run very quickly on its hind legs to the opposite side of a bush or a small sand hill, and run into a burrow or dive into the sand. Sometimes they will stop and freeze underneath a bush.

Habitat:

Range Found in extreme southeast California in the Colorado Desert from the Salton Sea and Imperial sand hills east to the Colorado River, south to the Colorado River delta and on into extreme northeastern Baja California. Ranges west as far as the east base of Borrego Mountain. From below sea level to 1,600 ft. (490 m). (Stebbins 2003) Habitat Sparsely-vegetated arid areas with fine wind-blown sand, including dunes, flats with sandy hummocks formed around the bases of vegetation, washes, and the banks of rivers. Needs fine, loose sand for burrowing.