Hoplophoneus primaevus

Real Fossil - Early Oligocene 35 Mya - White River Formation Wyoming
Named in 1874 by Edward Cope, Hoplophoneus is only found in North America. This false saber-toothed cat is only superficially similar to its feline relatives; for instance, unlike felines, Hoplophoneus walked flat footed instead of on its toes. It would have been a powerful predator, growing to the size of a modern leopard. This genus lasted approximately 3.9 million years before its extinction.