Quick Answer: Equinae is a subfamily of the family Equidae, which have lived worldwide from the Hemingfordian stage of the Early Miocene onwards. They are thought to be a monophyletic grouping. Members of the subfamily are referred to as equines; the only extant equines are the horses, asses, and zebras of the genus Equus. The subfamily contains two tribes, the Equini and the Hipparionini, as well as two unplaced genera Merychippus and Scaphohippus.