gomphothere

— The main lineage, the bunodont gomphotheres (called bunomastodonts by some authors), can be traced from Phiomia (from the Oligocene of North Africa) to Gomphotherium (a widespread Miocene genus), Tetralophodon (from the Old World and North America), and Stegomastodon (from the late Tertiary and early Pleistocene of North and South America).[…]Compared to the simple molars of the mastodonts, gomphothere molars are complex, with additional rounded cusps and accessory conules that wear to a complicated trefoil pattern.