Polycynodon

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Polycynodon
Temporal range: Late Permian
Scientific classification Red Pencil Icon.png
Kingdom: Animalia
Phylum: Chordata
Clade: Therapsida
Suborder: Therocephalia
Superfamily: Baurioidea
Genus: Polycynodon
Broom and Robinson, 1948
Type species
Polycynodon elegans
(Broom, 1940) (originally Octocynodon elegans)

Polycynodon is an extinct genus of therocephalians from the Late Permian of South Africa. It is known from the Cistecephalus Assemblage Zone. [1] The type species was first described as Octocynodon elegans by South African paleontologist Robert Broom in 1940, but the name Octocynodon was preoccupied by a genus of labrid fish first described in 1904. [2] Along with John T. Robinson, Broom instated Polycynodon as a replacement name for O. elegans in 1948. Polycynodon is classified in Baurioidea, although its relationship to other baurioid therocephalians is uncertain. [3]

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Ictidochampsa is an extinct genus of therocephalian therapsids from the Late Permian of South Africa. The type species Ictidochampsa platyceps was named by South African paleontologist Robert Broom in 1948 from the Dicynodon Assemblage Zone.

Ictidodon is an extinct genus of therocephalian therapsids from the Late Permian of South Africa. The type species Ictidodon agilis was named by South African paleontologist Robert Broom in 1925. Broom classified Ictidodon in the Scaloposauridae, a group of small-bodied therocephalians that are now thought to be juvenile forms of larger therocephalians. Ictidodon and many other scaloposaurids are now classified as basal members of the clade Baurioidea.

Silpholestes is an extinct genus of therocephalian therapsids from the Late Permian of South Africa. The type species Silpholestes jackae was named by South African paleontologist Robert Broom in 1948 from the Cistecephalus Assemblage Zone.

Ictidodraco is an extinct genus of therocephalian therapsids from the Late Permian of South Africa. The type species Ictidodraco longiceps was named by South African paleontologists Robert Broom and John T. Robinson in 1948 from the Cistecephalus Assemblage Zone. Ictidodraco was once classified as a scaloposaurian in the family Silpholestidae. Scaloposauria and Silpholestidae are no longer regarded as valid groups, and Ictidodraco is now classified as a basal member of the clade Baurioidea.

Pelictosuchus is an extinct genus of therocephalian therapsids from the Late Permian of South Africa. It is classified in the family Akidnognathidae. The type species Pelictosuchus paucidens was named by South African paleontologist Robert Broom in 1940 from the Dicynodon Assemblage Zone.

Lycideops is an extinct genus of therocephalians from the Late Permian of South Africa. The type species is Lycideops longiceps, named in 1931 by South African paleontologist Robert Broom. Fossils of Lycideops come from the Dicynodon Assemblage Zone of the Beaufort Group. Lycideops is a member of the family Lycideopidae. Like other lycideopids, Lycideops has a long snout.

Simorhinella is an extinct genus of therocephalian therapsids from the Late Permian of South Africa. It is known from a single species, Simorhinella baini, named by South African paleontologist Robert Broom in 1915. Broom named it on the basis of a single fossil collected by the British Museum of Natural History in 1878 that included the skull and jaws forward from the eye sockets. The skull is unusual in that it has an extremely short and deep snout, unlike the longer and lower snouts of most other therocephalians. Because of the skull's distinctiveness, the classification of Simorhinella within Therocephalia is uncertain. However, a 2014 study proposed that it was closely related to the basal therocephalian Lycosuchus, placing it in the family Lycosuchidae.

References

  1. Nicolas, M.; Rubidge, B.S. (2010). "Changes in Permo-Triassic terrestrial tetrapod ecological representation in the Beaufort Group (Karoo Supergroup) of South Africa". Lethaia. 43 (1): 45–59. doi:10.1111/j.1502-3931.2009.00171.x.
  2. "Genus: Octocynodon Fowler, 1904". Global Biodiversity Information Facility. GBIF. Retrieved 18 February 2012.
  3. Watson, D.M.S.; Romer, A.S. (1956). "A classification of therapsid reptiles". Bulletin of the Museum of Comparative Zoology. 114 (2): 37–89.