chuckwallas

Chuckwallas are large desert lizards in the genus Sauromalus, native to arid regions of the southwestern United States and northwestern Mexico. The two widely recognized species are the common chuckwalla (Sauromalus ater) and the desert chuckwalla (Sauromalus obesus). Some taxonomic treatments recognize additional regional forms, but these two are standard in field guides.

They have stout bodies, broad heads, and loose folds of skin around the neck and sides. Coloration varies by species and sex, ranging from gray to brown with olive or greenish tones; males may show brighter coloration during the breeding season. They can reach about 40 cm in total length.

Chuckwallas inhabit rocky, sparsely vegetated deserts with access to crevices for shelter. They are primarily diurnal, basking on sunny rocks to regulate body temperature, and retreat into rock crevices or burrows when threatened. A distinctive behavior is inflation: when alarmed, they tighten their jaws and fill their lungs to inflate the body and wedge themselves firmly into crevices as a defense against predators.

Dietwise, chuckwallas feed mainly on leaves, flowers, seeds, and fruits, with occasional insect prey. Reproduction is oviparous, with eggs laid in spring or early summer and a several-week incubation period. In the wild, lifespans typically exceed a decade; in captivity, individuals can live 20 years or more. Chuckwallas are not currently listed as globally threatened, though local populations can be affected by habitat disturbance and collection.