Andrewsarchus

Andrewsarchus is an extinct genus of mammal that lived during the middle Eocene epoch in what is now Inner Mongolia, China. Only one species is usually recognized, A. mongoliensis, known from a single skull of great size discovered in 1923 during the expeditions of central Asia by the American Museum of Natural History. Generally classified as a mesonychid since its original description, most recent studies recover it as an artiodactyl, in one study specifically, as a member of the clade Cetacodontamorpha, closely related to entelodonts, hippos and whales.