Tiny gray insectivore of scrubby areas in the southwest U.S. and northern Mexico. Breeding males show a black cap with a thin white eyering; nonbreeding males have a thin black line over the eye. Females lack any black on the head. Note tail pattern from below: mostly black with bold white spots. Prefers dry, scrubby habitats such as desert washes, where pairs flit around in the low bushes. Listen for harsh scolding calls. Compare with Blue-gray Gnatcatcher, but note Black-tailed often looks drabber brownish-gray, and has much more black on the underside of the tail.