''Choerosaurus'' is an extinct

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

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

n therapsids from the

Late Permian Late or LATE may refer to: Everyday usage * Tardy, or late, not being on time * Late (or the late) may refer to a person who is dead Music * ''Late'' (The 77s album), 2000 * Late (Alvin Batiste album), 1993 * Late!, a pseudonym used by Dave Groh ...

South Africa South Africa, officially the Republic of South Africa (RSA), is the Southern Africa, southernmost country in Africa. Its Provinces of South Africa, nine provinces are bounded to the south by of coastline that stretches along the Atlantic O ...

. The

type species In International_Code_of_Zoological_Nomenclature, 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 spe ...

''Choerosaurus dejageri'' was named by South African paleontologist Sidney H. Haughton 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 Annum, Ma existing for approximately . Taxonomy ''Scaloposaurus'' was named by Richard Owen, Owen (1876). It was assigned to Therocephal ...

''. 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 lies over the occipital lobes of the ...

) 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 that includes organisms with mixed evolutionary origin but does not include their most recent common ancestor. The term is often applied to groups that share similar features known as Homoplasy, homoplasies ...

grouping of mostly juvenile therocephalians, and most taxa are now classified as basal members of

Baurioidea Baurioidea is a superfamily of therocephalian therapsids. It includes advanced therocephalians such as ''Regisaurus'' and ''Bauria''. The superfamily was named by South African paleontologist Robert Broom in 1911. Bauriamorpha, named by D. M. ...

. The position of ''Choerosaurus'' within Baurioidea is uncertain, as it has never been incorporated in a

phylogenetic In biology, phylogenetics () is the study of the evolutionary history of life using observable characteristics of organisms (or genes), which is known as phylogenetic inference. It infers the relationship among organisms based on empirical dat ...

analysis.

References

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