The species is native to the southwestern United States and adjacent northern Mexico.

U. graciosus occurs in the Mojave Desert and the northwestern Sonoran Desert in the U.S. states of California, Arizona and Nevada, and in the Mexican states of Baja California and Sonora.

The long-tailed brush lizard's gray or tan coloration keeps it well camouflaged against branches while it waits for insects.

U. graciosus is distinguishable from its close relative the tree lizard, Urosaurus ornatus, by the presence of a tail more than two times its snout-vent length and the absence of a series of smaller scales running down the middle of the band of enlarged dorsal scales.

[2] The subspecific name, shannoni, is in honor of American herpetologist Frederick Albert Shannon.