Collared lizard (Crotaphytus), Alibates Flint Quarries National Monument, 2015.

Collared lizards are native to arid environments in the southwestern portion of North America. Named for the distinctive collar pattern around its neck, a collared lizard can be spotted easily along sunny trails as it suns itself on rocks. A collard lizard is also a very capable runner, often lifting its front half to run only on its hind legs! Unlike many lizard species, however, it is not able to break off and regenerate its tail if attacked. Because of its running prowess, the collard lizard needs its tail for balance. Males are generally more colorful than females and can be very territorial. If you find one on a trail and see it start to do a push-up like maneuver, back away. You are too close and it is warning you to stay away.