Huayangosaurus taibaii

An early stegosaur from the Middle Jurassic of Sichuan, China, Huayangosaurus was about 4.7 meters (15 feet) long. More primitive than later stegosaurs, it retained teeth at the front of its beak and supplemented the paired plates and spikes along its back with armor down the sides, a shoulder spike and a strange little club at the end of the tail.