Petrolacosaurus

Petrolacosaurus

• Kansas ( North America )

Petrolacosaurus was a genus of Araeoscelidia, a lizard-like family, who were probably the most original diapsiden reptiles. Only species described is Petrolacosaurus kansensis. Fossils of Petrolacosaurus were first found in the 1930s in Kansas, USA.

Features

Petrolacosaurus was a slender lizard that was about 40 cm long. Compared with Hylonomus the head is relatively small and accounts for less than one-fifth of the body length from. The skull has larger orbit, two temporal windows and a larger number of small teeth on the palate. The snout was short. The teeth on the mandibular border were sharp and suggest the Petrolacosaurus of insects and other small animals fed on. In addition to the posterior nares ( the paired posterior openings of the nasal cavity ), which are present in all terrestrial vertebrates can be found on the right and left side of the palate, two further openings Suborbitalfenster. Neck and legs are longer than Hylonomus. Maybe Petrolacosaurus was a fast runner.