The greater earless lizard (Cophosaurus texanus) is the only species in the monotypic genus Cophosaurus. It is closely related to the smaller, lesser earless lizards and other species in the genus Holbrookia, and in fact was placed in that genus and referred to Holbrookia texana from 1852 into the 1970s. Earless lizards lack external ear openings, an adaptation to burrowing in the sand, as are the recessed lower jaw and flared upper labial scales. Greater earless lizards are sexually dimorphic, males grow larger and are more colorful than females, exhibiting pink and green colors that are particularly bright in the breeding season. Two bold black bars mark the lateral region of males but are greatly reduced and vague, or occasionally entirely absent in females. The greater earless lizard is native to the Chihuahua Desert and other arid and semi-arid regions of Southwestern United States and northern Mexico, where they most often occupy moderately open areas of sparse vegetation with rocks, gravel, and sand. The overall color of individual lizards frequently match the colors of the rocks and soils of the local area they inhabit. They will often rely on camouflage and their speed to elude threats and predators before retreating into rock crevices. They are primarily insectivores, preying on wide variety of crickets, grasshoppers, caterpillars, ants, flies, beetles, and bugs. Spiders and small lizards are occasionally eaten as well. Cophosaurus are oviparous. Females lay 1 to 4 clutches of 2 – 9 eggs a year, with hatchlings emerging from June to October, and reaching adult size and sexual maturity in one year. Etymology The generic name Cophosaurus, is derived from the Greek words copho (κουφός) meaning deaf, and saurus meaning lizard, in reference to the absents of external ear openings in the species. The trivial name, or specific epithet texanus, is a toponym in reference to the state of Texas where the specimens used in the original description were collected. The subspecies names are both Latin, reticulatus meaning reticulated or a net-like pattern, and scitulus meaning handsome or pretty. Taxonomy Within the family Phrynosomatidae, Cophosaurus is most closely related to Zebra-Tailed Lizards (Callisaurus), Lesser Earless Lizards (Holbrookia), and Fringe-Toed Lizards (Uma), collectively forming the Tribe Callisaurini, commonly referred to as sand lizards. The genus Cophosaurus is monotypic, meaning Cophosaurus texanus is the only species in the genus. Franz Hermann Troschel described the genus Cophosaurus as well as the species C.