DESCRIPTION A large (up to 140 mm or 5.5- from snout to vent), smooth and shiny lizard with a long body, small limbs, and a long, thick tail. Base coloration is usually tan or gray. Dark brown to red-brown crossbars with dark posterior edges mark the back. There are usually crisp black and white markings on the lips. The original tail is more than twice the length of the body. The back and belly are armored with large, stiff, rectangular, scales that are reinforced with bony plates. A soft fold of skin covered with small rounded scales runs along each lower side of the body from the corner of the mouth to the hind limbs. These folds of skin allow the body to expand for breathing, ingesting prey, and egg development. Males have a broad head and crisp, distinct dorsal pattern. Adult females have a relatively pale dorsal pattern, usually lacking dark posterior borders on the crossbands. Juveniles are marked with distinct dark and light bands on the body and tail, dark limbs, and white spots on the lips.