Psittacosaurus sinensis
"Chinese parrot lizard"

One of the basal-most ceratopsians, Psittacosaurus is so primitive it looks almost nothing like it's horned successors. Actually, despite its appearance, Psittacosaurus is a transitional form between early, ornithopod-like dinosaurs such as Heterodontosaurus and coronosaurs like Leptoceratops. It's generally assumed that Psittacosaurus was bipedal, like it's heterodontosaur predecessors, but due to it's transitional nature, along with it's fairly long forelimbs and curved femur, it probably was a facultative quadruped. A new specimen from the famous Liaoning of China, which preserves the outer skin covering and feathers of many dinosaurs, has given us a good idea what the outward appearance of  Psittacosaurus was like. We now know that this species had a covering of small round scales, with larger scutes over the shoulder, and most surprisingly, a large array of bristle-like structures on the tail, similar to the spines of a porcupine.

Psittacosaurus was small at about 1 meter (3ft) long. It lived in the Early Cretaceous, and species have been found in China, Mongolia, and Russia.