General: Darkling Beetles (Family Tenebrionidae), also called Circus Beetles and Stinkbugs, are fairly common beetles of the desert and are often seen walking across roads and trails. When threatened, these beetles defend themselves by lifting their rear end into the air and spraying noxious and burning chemicals (i.e., the stink in "stinkbug") into the mouth and face of an attacker.

There are several genera of Darkling beetles around Las Vegas; each is a different size and surface texture. Some are small (1/2-inch long) with a rough back, some are large (3/4-inch long) with grooved backs, some are hairy, but the ones most often seen are large (about 1-inch long) with smooth backs.