''Pareiasaurus'' is an

extinct Extinction is the termination of a kind of organism or of a group of kinds (taxon), usually a species. The moment of extinction is generally considered to be the death of the last individual of the species, although the capacity to breed and ...

genus of pareiasauromorph

reptile Reptiles, as most commonly defined are the animals in the class Reptilia ( ), a paraphyletic grouping comprising all sauropsids except birds. Living reptiles comprise turtles, crocodilians, squamates (lizards and snakes) and rhynchocephalians ( ...

from the Permian period. It was a typical member of its family, the

pareiasaurids Pareiasaurs (meaning "cheek lizards") are an extinct clade of large, herbivorous parareptiles. Members of the group were armoured with scutes which covered large areas of the body. They first appeared in southern Pangea during the Middle Permian, ...

, which take their name from this genus. Fossils have been found in the Beaufort Group.

Description

''Pareiasaurus'' is a large quadruped, about long, with elephantine legs, walking in a typically reptilian posture. The skull is broad and the snout short. Its skull had several spine- and wart-like protrusions. ''Pareiasauruss leaf-shaped teeth, ideal for biting through tough plant fibers, indicate it was a herbivore. Even the palate had teeth.

Species

''P. nasicornis'' (Haughton and Boonstra, 1929) is from the ''Tropidostoma'' Zone, Karoo basin, South Africa. This early form is one of the first representatives of the genus. It was originally included under the genus ''Pareiasuchus''. The snout is heavily armoured, and bears a horn-like boss. The teeth are equipped with 11 (or possibly 13 or 15) cusps. This is a large animal; the skull is about 50 cm in length. This species might be ancestral to ''Pareiasaurus peringueyi''. ''P. peringueyi'' (Haughton and Boonstra, 1929) is from the ''Cistecephalus'' Zone, Karoo basin, South Africa. It is represented by a nearly complete skeleton from the Zak River, South Africa. It is a medium-sized animal, the skull being 36 cm long. It is distinguished especially by the large quadrato-jugal region inclined far outwards and forwards so that its lower border makes an angle of about 120° with the maxillary border; this cheek bears large bony bosses. There are at least 13 pairs of teeth in the upper jaw, each with 13 or possibly 15 cusps. ''P. serridens'' (Owen, 1876) is from the ''Dicynodon'' Zone, Karoo basin, South Africa. This species was the type species for ''Pareiasuchus''. This late species is the type species for ''Pareiasaurus'', and represents the culmination of this lineage. The armour is well developed. There are 14 pairs of teeth, each with 9 to 11 cusps. The short deep skull is about 40 cm in length. Note the extended quadrato-jugal region (cheek bones).

References

External links

Pareiasaurinae
at Palaeos Pareiasaurs Permian reptiles of Africa Permian reptiles of Europe Fossil taxa described in 1876 Wuchiapingian genus first appearances Changhsingian genus extinctions Prehistoric reptile genera {{permian-reptile-stub