- an extinct canid species, Aenocyon dirus, with two recognized subspecies (A. dirus dirus and A. dirus guildayi), living in the Americas and eastern Asia during the Late Pleistocene and Early Holocene epochs: similar in size to the largest modern gray wolf (Canis lupus), but with larger, more powerful teeth suited for preying upon large prehistoric herbivores, such as mastodons, bison, camels, and horses.
