N. America S. America Chuckwalla Sauromalus obesus Range Southern Nevada to Guayman, Mexico, southern California to central Arizona, southern Utah. This is the largest of the southwest desert lizards except for the Gila Monster. It has a flat dark body with loose folds of skin on the neck and sides. The skin has a sandpaper texture. The tail has a blunt tip and broad base.
Females tend to retain juvenile crossbands.
Adults of both sexes are usually banded in Southwestern Utah. The tail bands are conspicuously black on an olive-gray or yellow background. The tail is pale yellow. During the late morning and afternoon it is often found basking in the sun. It may open its mouth and huff or hiss at an intruder.