In southwestern Wyoming, adult Omninablautus nigronotum (Wilcox) hunted primarily from the surface of sandy substrate in a greasewood community. Prey, captured in flight, represented four insect orders with Diptera and Hymenoptera predominating. Courtship consisted of the male approaching the female from the front, bobbing up and down, simultaneously waving its fore tarsi, and weaving back and forth. The flies positioned themselves linearly for mating following initial copulation in the male atop female position.