They are often seen basking on large boulders, but are wary and difficult to catch midday when temperatures are warm. Life Cycle Black-Collared Lizards mate in May and June, with the female laying 4 to 8 eggs midsummer in sandy soils, burrows or under rocks. They have broad heads, large mouths and narrow necks. They are 6 to 13 inches from snout to end of tail, which is flattened from side to side. They are tan to olive in color with pale yellow crossbands and small white spots.
Mature males have blue-gray throats with a black center.
Males are also black in the groin and the gular area. Gravid females show yellow-orangish spots along the sides. The young usually have bright crossbanding with no throat coloring. There are 2 common species of Black-Collared Lizards inhabiting the deserts of the Southwest. The Mojave Black-Collared is C.bicinctores .