Pareiasaurus

{{Short description|Extinct genus of reptiles}} {{Automatic Taxobox |fossil_range = Wuchiapingian - Changhsingian, {{fossilrange|260|252}} |image = Pareiasaurus serridens00.jpg |image_caption = Cast of distorted skull of juvenile ''P. serridens'' collected in February 1946 by James W. Kitching |taxon = Pareiasaurus |authority = Owen, 1876 |type_species = {{extinct}}'''''Pareiasaurus serridens''''' |type_species_authority = Owen, 1876 |subdivision_ranks = Species |subdivision = * {{extinct}}'''''P. nasicornis''''' Haughton and Boonstra, 1929 * {{extinct}}'''''P. peringueyi''''' Haughton and Boonstra, 1929 * {{extinct}}'''''P. serridens''''' Owen, 1876 | synonyms = {{species list |Anthodon gregoryi|Broom, 1930 |Anthodon nesemanni|Broom, 1940 |Brachypareia rogersi|Broom, 1912 |Bradysaurus rogersi|Broom, 1912 |Pareiasaurus minor|Seeley, 1892 |Pareiasaurus omocratus|Seeley, 1888 |Pareiasaurus pinnatus|Olson & Broom, 1937 |Pareiasaurus pulcher|Broom, 1935 |Pareiasaurus rubidgei|Broom, 1940 |Pareiasuchus nasicornis|Haughton & Boonstra, 1929 |Pareiasuchus peringueyi|Broom & Haughton, 1913 |Propappus omocratus|Seeley, 1888 |Propappus serridens|Owen, 1876 |Propappus rogersi|Broom, 1912}} }}

'''''Pareiasaurus''''' (from {{langx|el|pareia}}, "cheek" and {{langx|el|sauros}}, "lizard")<ref>{{cite book |last1=Colbert |first1=Edwin H. (Edwin Harris) |last2=Knight |first2=Charles Robert |title=The dinosaur book: the ruling reptiles and their relatives |date=1951 |publisher=McGraw-Hill |location=New York |page=152 |url=https://archive.org/details/bookruli00colb/page/152/mode/2up}}</ref> is an extinct genus of pareiasauromorph reptile from the Permian period. It was a typical member of its family, the pareiasaurids, which take their name from this genus.

Fossils have been found in the Beaufort Group.<ref name="schwarz">{{cite book|last1=Schwarz|first1=Ernest Hubert Lewis|title=South African Geology|url=https://archive.org/details/southafricangeol00schwrich|date=1912|page=[https://archive.org/details/southafricangeol00schwrich/page/156 156]}}</ref>

==Description== thumb|left|Restoration of ''P. serridens'' thumb|left|Skeleton of ''P. serridens'' ''Pareiasaurus'' is a large quadruped, about {{convert|2.5|m|ft}} 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. ''Pareiasaurus'''s leaf-shaped teeth, ideal for biting through tough plant fibers, indicate it was a herbivore. Even the palate had teeth.<ref name=EoDP>{{cite book |editor=Palmer, D.|year=1999 |title= The Marshall Illustrated Encyclopedia of Dinosaurs and Prehistoric Animals|publisher= Marshall Editions|location=London|page= 63|isbn= 1-84028-152-9}}</ref>

==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== {{Reflist}}

==External links== * [http://palaeos.com/vertebrates/anapsida/pareiasauridae3.html#Scutosaurus Pareiasaurinae] at Palaeos

Category:Pareiasauria Category:Permian reptiles of Africa Category:Permian reptiles of Europe Category:Fossil taxa described in 1876 Category:Lopingian life Category:Wuchiapingian life Category:Changhsingian life Category:Wuchiapingian genus first appearances Category:Changhsingian genus extinctions Category:Prehistoric reptile genera