southern state line in eastern San Luis Potosí. Several accounts have commented on the problematic and poorly defined zone of integration between the subspecies C. t. texanus and C. t. scitulu. The Chihuahuan greater earless lizard (C. t. scitulus) occurs throughout much of the Chihuahua Desert, including much of the Trans-Pecos region of west Texas, the southern third of New Mexico (following the Pecos and Rio Grande river basins northward), into southeast Arizona east of the Sonora Desert, and following a zone of semi-arid habitat around the northeast margins of the Sonora Desert almost to the California border. In Mexico it ranges into northeast Chihuahua, much of Coahuila, northeast Durango, extreme northeast Zacatecas, extreme southern Nuevo León, northern San Luis Potosí, and extreme southwest Tamaulipas. It is absent from the higher elevations in the Sierra Madre Oriental but it does range deep into the canyons and valleys on both the eastern and western versants of the mountain range. The Sonoran greater earless lizard (C. t. reticulatus) is endemic to northeastern Sonora, Mexico, between 470 – 1300 meters, where as recently as 2016 it was reportedly known from only eight localities. Ecology and natural history Reproduction The longevity of the greater earless lizard is typicality 3 years, but records of individuals surviving five reproductive seasons in the wild have been documented. Both males and females reach adult size in a year, attaining maturity and mating before their second winter. Mating occurs from April to August, peeking in late April to early July. Gravid females often exhibit pink, orange, or yellow colors on their throats and sides. In one study gravid females were only found in May and June. Multiple clutches, up to four a year, are scattered over a wide area, with clutch size ranging from 2 to 9 eggs, average 3–5. Older females produce larger clutches than young females. One study reported finding single eggs buried in the sand on three occasions but never locating a clutch. The incubation period is about 50 days. The hatchlings emerge June to October with reports of sizes varying from 20–25 mm. to 26–31 mm. snout–vent length. Diet The greater earless lizard is predominantly an insectivore and a generalist. A study in Mohave County, Arizona found insects comprised 85% of the diet, including 18.2% Orthoptera (crickets, grasshoppers, locusts), 15.8% Hymenoptera (ants, bees, sawflies, wasps), and 10.1% Lepidoptera (butterflies and moths), 9.2% Diptera (flies), 9.2%