Arctognathus

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Arctognathus
Temporal range: 259.9–252.17  Ma
Arctognathus curvimola.jpg
Life restoration of A. curvimola
Scientific classification OOjs UI icon edit-ltr.svg
Domain: Eukaryota
Kingdom: Animalia
Phylum: Chordata
Clade: Synapsida
Clade: Therapsida
Clade: Gorgonopsia
Family: Gorgonopsidae
Genus: Arctognathus
Broom, 1911
Species
  • A. curvimola(Owen, 1876 [originally Lycosaurus curvimola]) (type)
Synonyms
  • ArctognathoidesBoonstra, 1934
  • LycaenodontoidesHaughton, 1924

Arctognathus is an extinct genus of gorgonopsids that throve during the Late Permian in the Karoo basin of what is now South Africa. [2]

Contents

Discovery

1886 illustration of a A. curvimola skull Arctognathus curvimola old.jpg
1886 illustration of a A. curvimola skull

A carnivore, like all gorgonopsid, Arctognathus was given its name ("Bear jaw") in reference to its short and rounded snout. There is only one recognized species, A. curvimola. [3]

Description

It was a small gorgonopsid with a total length estimated at 1.1 m and an 18 cm skull. [4]

Classification

Restoration of A. curvimola in environment Arctognathus BW.jpg
Restoration of A. curvimola in environment
Head of A. curvimola Arctognathus 2sp.jpg
Head of A. curvimola

Below is a cladogram from the phylogenetic analysis of Gebauer (2007): [5]

Gorgonopsia

See also

Related Research Articles

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<i>Rubidgea</i> Extinct genus of therapsids

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<i>Aloposaurus</i> Extinct genus of therapsids

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<i>Aelurosaurus</i> Extinct genus of therapsids

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<i>Broomisaurus</i> Extinct genus of therapsids

Broomisaurus is an extinct genus of Gorgonopsia. It was first named by Joleaud in 1920, and contains the single species B. planiceps. Gebauer (2007) considered Broomisaurus to be a nomen dubium, indistinguishable as a separate taxon of gorgonopsian because it is based on only a fragmentary remains. A 2015 paper on Eriphostoma tentatively agreed with Gebauer's determination, but did not rule out the possibility that Broomisaurus might be synonymous with Eriphostoma.

<i>Bullacephalus</i> Extinct genus of animal

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<i>Eriphostoma</i> Extinct genus of therapsids

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<i>Kawingasaurus</i> Extinct genus of dicynodonts

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"Dixeya" nasuta is a extinct species of gorgonopsian that lived during the Late Permian of East Africa, known from fossils found in what is now Tanzania. The species has a complicated taxonomic history, it was originally named as a second species of the genus Dixeya which is now considered a junior synonym of Aelurognathus. "D." nasuta itself, however, was not moved to Aelurognathus, and although it was instead tentatively referred to Arctognathus at first it has since been recognised to not belong to this genus either. This situation leaves "Dixeya" nasuta without a formal genus name. It was proposed to belong to a new distinct genus, named "Njalila", that was informally proposed for the species in a PhD thesis, but this name has not yet been formally published and is currently a nomen nudum. "D." nasuta has been characterised from other gorgonopsians by a combination of its straight snout profile, upturned and "pinched" nose, and curved jaw margin. The fossil record of the Usili Formation shows that the taxon was contemporary with many other gorgonopsians, even alongside large representatives such as Inostrancevia and rubidgeines.

Cynodraco, also spelled Cynodracon or Cynodrakon, is a dubious genus of non-mammalian therapsid, probably gorgonopsian, from the late Permian of South Africa. Two species of the genus have been named, Cynodraco serridens and Cynodraco major. Its fossils have been found in the Cistecephalus Assemblage Zone, which dates to the Wuchiapingian age of the late Permian. Cynodraco was one of the first gorgonopsian taxa named, alongside Gorgonops and Lycosaurus, which were named in the same publication.

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<i>Abdalodon</i> Extinct genus of cynodonts

Abdalodon is an extinct genus of late Permian cynodonts, known by its only species A. diastematicus.Abdalodon together with the genus Charassognathus, form the clade Charassognathidae. This clade represents the earliest known cynodonts, and is the first known radiation of Permian cynodonts.

<i>Leucocephalus</i> Extinct genus of therapsids

Leucocephalus is a genus of biarmosuchian belonging to the family Burnetiidae dating to the Wuchiapingian. It was found in the Tropidostoma Assemblage Zone of the Main Karoo Basin of South Africa. It is a monotypic taxon which contains one only species, Leucocephalus wewersi. The genus name Leucocephalus is derived from Greek. Leucos, meaning white; kephalos, meaning skull, as the Leucocephalus skull discovered was unusually pale. The species epithet wewersi comes from the farm employee who found the skull, Klaus ‘Klaasie’ Wewers.

<i>Thliptosaurus</i> Extinct genus of dicynodonts

Thliptosaurus is an extinct genus of small kingoriid dicynodont from the latest Permian period of the Karoo Basin in KwaZulu-Natal, South Africa. It contains the type and only known species T. imperforatus. Thliptosaurus is from the upper Daptocephalus Assemblage Zone, making it one of the youngest Permian dicynodonts known, living just prior to the Permian mass extinction. It also represents one of the few small bodied dicynodonts to exist at this time, when most other dicynodonts had large body sizes and many small dicynodonts had gone extinct. The unexpected discovery of Thliptosaurus in a region of the Karoo outside of the historically sampled localities suggests that it may have been part of an endemic local fauna not found in these historic sites. Such under-sampled localities may contain 'hidden diversities' of Permian faunas that are unknown from traditional samples. Thliptosaurus is also unusual for dicynodonts as it lacks a pineal foramen, suggesting that it played a much less important role in thermoregulation than it did for other dicynodonts.

Kembawacela is an extinct genus of cistecephalid dicynodont from the Late Permian of East Africa. The genus contains two known species, the type species Kembawacela kitchingi from the Madumabisa Mudstone Formation of Zambia described in 2019, and a second species, K. yajuwayeyi, from the Chiweta Beds of Malawi described in 2022. Like other cistecephalids, Kembawacela was specialised for a fossorial, burrowing lifestyle similar to modern day moles. It is unique amongst cistecephalids for the presence of a pair of tusks in the upper jaw, characteristic of many other dicynodonts but lost in other cistecephalids. It is likely that Kembawacela was a locally endemic species of cistecephalid in the Luangwa Basin of Zambia.

References

  1. "Arctognathus". paleobiodb.org. Retrieved 2021-10-10.
  2. Sidor 2003 , p. 606
  3. Christian F. Kammerer (2014) Cranial osteology of Arctognathus curvimola, a short-snouted gorgonopsian from the Late Permian of South Africa. Papers in Palaeontology (advance online publication) DOI: 10.1002/spp2.1002 http://onlinelibrary.wiley.com/doi/10.1002/spp2.1002/abstract
  4. "Arctognathus - Palaeocritti - a guide to prehistoric animals". Archived from the original on April 3, 2016.
  5. Gebauer, E.V.I. (2007). Phylogeny and evolution of the Gorgonopsia with a special reference to the skull and skeleton of GPIT/RE/7113 ('Aelurognathus?' parringtoni) (PDF) (Ph.D. thesis). Tübingen: Eberhard-Karls Universität Tübingen. pp. 1–316.

Bibliography