Psittacosaurus is a genus of extinct ceratopsian dinosaur from the Early Cretaceous of what is now Asia. Up to 12 species are known, from across China, Mongolia, Siberia, and possibly Thailand and Laos. The best-known species, P. mongoliensis, can reach 2metres in length. Psittacosaurs were obligate bipeds at adulthood, with a high skull and a robust beak.
About Psittacosaurus in brief
Psittacosaurus is a genus of extinct ceratopsian dinosaur from the Early Cretaceous of what is now Asia. Up to 12 species are known, from across China, Mongolia, Siberia, and possibly Thailand and Laos. The best-known species, P. mongoliensis, can reach 2metres in length. Psittacosaurs were obligate bipeds at adulthood, with a high skull and a robust beak. One individual was found preserved with long filaments on the tail, similar to those of Tianyulong, and scales across the rest of the animal. It was described while awaiting repatriation from China, but was purchased by the Senckenberg Museum in Germany in violation of Chinese law. The specimen, which is not yet assigned to any particular species, was arranged in irregular patterns in Larger scales in Liaixian Province, China. Most of the body was covered in irregular scales in L larger scales, which were arranged in larger patterns in the Yixian Formation of Liaixoning Province. It is thought to be an example of convergent evolution, or evolution of the integument or body covering, covering the body of a bipedal ornithischian. It may have been active for short periods of time during the day and night, and had well-developed senses of smell and vision. It probably had complex behaviours, based on the proportions and relative size of the brain.
The genus is now considered to be a senior synonym of the PsittACosauridae, with other genera like Hongshanosaurus, and an early offshoot of the branch that led to more derived forms. The first species was either P. lujiatunensis or closely related, and it may have given rise to later forms of Psitt ACosaurus. The abundance of this dinosaur in the fossil record has led to the labelling of Lower Cretsaceous sediments of east Asia the Psitacosaurus biochron. The species of PsITTacosaurus vary in size and specific features of the skull and skeleton, but share the same overall body shape. There are only four digits on the manus, as opposed to the five found in most other ornithischerians, while the four-toed hindfoot is very similar to many other small Ornithischians. As the generic name suggests, the short skull and beak superficially resemble those of modern parrots. There is still no sign of the bony frill or prominent facial horns which would develop in later generations of the species. The smallest known species is P. ordosensis, is 30% smaller than P. mongliensis. The largest are P. sibiricus, although neither is significantly larger than P. mongolienis, although both are significantly larger. The maximum adult body weight was most likely over 20 kilogrammes in P. penglienis.