''Choerosaurus'' is an extinct

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of living and fossil organisms as well as viruses. In the hierarchy of biological classification, genus comes above species and below family. In binomial nom ...

therocephalia Therocephalia is an extinct suborder of eutheriodont therapsids (mammals and their close relatives) from the Permian and Triassic. The therocephalians ("beast-heads") are named after their large skulls, which, along with the structure of their ...

therapsid Therapsida is a major group of eupelycosaurian synapsids that includes mammals, their ancestors and relatives. Many of the traits today seen as unique to mammals had their origin within early therapsids, including limbs that were oriented more ...

s from the

Late Permian Late may refer to: * LATE, an acronym which could stand for: ** Limbic-predominant age-related TDP-43 encephalopathy, a proposed form of dementia ** Local-authority trading enterprise, a New Zealand business law ** Local average treatment effect, ...

South Africa South Africa, officially the Republic of South Africa (RSA), is the Southern Africa, southernmost country in Africa. It is bounded to the south by of coastline that stretch along the Atlantic Ocean, South Atlantic and Indian Oceans; to the ...

. The

type species In zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the species that contains the biological type specime ...

''Choerosaurus dejageri'' was named by South African paleontologist

Sidney H. Haughton Sidney Henry Haughton FRS (7 May 1888 – 24 May 1982) was an English-born South African paleontologist and geologist best known for his description of the sauropodomorph dinosaur '' Melanorosaurus'' in 1924, and his work on the geology of ...

from the ''Tropidostoma'' Assemblage Zone in 1929. Choerosaurus fighting

''Choerosaurus'' is similar in appearance to ''

Scaloposaurus ''Scaloposaurus'' is an extinct genus of carnivorous therocephalians living during the Permian 259.0—254.0 Ma existing for approximately . Taxonomy ''Scaloposaurus'' was named by Owen (1876). It was assigned to Therocephalia by Broom (1913); ...

''. In both ''Choerosaurus'' and ''Scaloposaurus'', the back of the skull (called the

occiput The occipital bone () is a cranial dermal bone and the main bone of the occiput (back and lower part of the skull). It is trapezoidal in shape and curved on itself like a shallow dish. The occipital bone overlies the occipital lobes of the cereb ...

) is high and the canine teeth are thick and shortened. ''Choerosaurus'' also has teeth that are ankylothecodont, meaning that they are fused to the bone of the jaw and would not have been replaced when it was alive. ''Choerosaurus'' was traditionally classified in the Scalopodontia, a group of small therocephalians. Scalopodontians are now thought to be a

polyphyletic A polyphyletic group is an assemblage of organisms or other evolving elements that is of mixed evolutionary origin. The term is often applied to groups that share similar features known as homoplasies, which are explained as a result of conver ...

grouping of mostly juvenile therocephalians, and most taxa are now classified as basal members of Baurioidea. The position of ''Choerosaurus'' within Baurioidea is uncertain, as it has never been incorporated in a

phylogenetic In biology, phylogenetics (; from Greek φυλή/ φῦλον [] "tribe, clan, race", and wikt:γενετικός, γενετικός [] "origin, source, birth") is the study of the evolutionary history and relationships among or within groups o ...

analysis.

References

Lopingian synapsids of Africa Baurioids Lopingian genus first appearances Lopingian genus extinctions Therocephalia genera {{paleo-therapsid-stub