Night Lizards: Xantusiidae

The night lizards are mainly small lizards without the working eyelids that many other species of lizards have. Instead, the night lizards have a see-through scale covering the eye. This clear scale, which looks somewhat similar to a person's contact lens, is called a spectacle. Beneath the spectacle, the eyes of some species of night lizards have catlike pupils, but others have round pupils. The typical night lizard has a low flat body, which allows it to sneak easily into cracks of rocks or into narrow openings between plant leaves.

The bodies of these lizards are covered with small scales, except on the head and belly. The top of the head is covered with large plates, and wide rectangular scales stretch across the belly. Most have drab-colored bodies, usually brown or gray, but a few have striking patterns. The granite night lizard, for example, has a spotted leopard-style pattern of brown spots on an otherwise yellowish body. Some have round and bumpy scales that give the lizard's back the look of a tiny beaded purse. Some night lizards are quite small, reaching only 1.5 inches (3.7 centimeters) long from the tip of the snout to the vent, a slit-like opening at the beginning of the tail and on the underside of the lizard. Adults of the largest species, the yellow-spotted night lizard, grow to more than three times that size, reaching 5 inches (12.7 centimeters) long from the snout to the vent. The typical night lizard has a tail as long or slightly longer than its body.