''Aelurosaurus'' ("cat lizard", from

Ancient Greek Ancient Greek includes the forms of the Greek language used in ancient Greece and the ancient world from around 1500 BC to 300 BC. It is often roughly divided into the following periods: Mycenaean Greek (), Dark Ages (), the Archaic peri ...

"cat" and "lizard") is a small,

carnivorous A carnivore , or meat-eater (Latin, ''caro'', genitive ''carnis'', meaning meat or "flesh" and ''vorare'' meaning "to devour"), is an animal or plant whose food and energy requirements derive from animal tissues (mainly muscle, fat and other sof ...

, extinct genus of

gorgonopsia Gorgonopsia (from the Greek Gorgon, a mythological beast, and 'aspect') is an extinct clade of sabre-toothed therapsids from the Middle to Upper Permian roughly 265 to 252 million years ago. They are characterised by a long and narrow skull, a ...

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

Middle Permian The Guadalupian is the second and middle series/epoch of the Permian. The Guadalupian was preceded by the Cisuralian and followed by the Lopingian. It is named after the Guadalupe Mountains of New Mexico and Texas, and dates between 272.95 ± 0. ...

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 southernmost country in Africa. It is bounded to the south by of coastline that stretch along the South Atlantic and Indian Oceans; to the north by the neighbouring countri ...

. It was discovered in the Karoo Basin of South Africa, and first named by

Richard Owen Sir Richard Owen (20 July 1804 – 18 December 1892) was an English biologist, comparative anatomist and paleontologist. Owen is generally considered to have been an outstanding naturalist with a remarkable gift for interpreting fossils. Owe ...

in 1881. It was named so because it appeared to be an ancestor for cat-like marsupials, but not yet a mammal itself. It contains five species, ''A. felinus'', ''A. whaitsi, A. polyodon'', ''A. wilmanae, and A.? watermeyeri''.Owen, R. 1881. On the order Theriodontia with a description of a new genus and species (Aelurognathus fel. Ow.). Quat. Jour. Geol. Soc. London. (Vol. 37): 261–265. ''A. felinus'', the type species, is generally well described with established features, while the other four species are not due to their poorly preserved holotypes. __TOC__

Discovery

''Aelurosaurus'' was discovered in 1881 in the

Karoo Basin The Karoo Supergroup is the most widespread stratigraphy, stratigraphic unit in Africa south of the Kalahari Desert. The group (stratigraphy), supergroup consists of a sequence of units, mostly of nonmarine origin, deposited between the Pennsylvan ...

of South Africa. The skull

holotype A holotype is a single physical example (or illustration) of an organism, known to have been used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of several ...

was missing the postorbital region, so Owen was left to describe the anterior portion. After examining the sutures and teeth, he assumed the first specimen to be from an older, adult ''Aelurosaurus'', seeing that they were no longer in perfect condition.

Species

''A. felinus''

Originally described by Owen, the orbit is a 2.5 centimeters by 2 centimeters ellipse, and the nostril 1.3 centimeters wide and 0.9 centimeters long. The upper jaw has a maximum width of roughly 3.5 centimeters just below the orbits. At a little more than 7.5 centimeters long and 2 centimeters wide, the mandible spans almost the entirety of the skull. This particular specimen was preserved with the mouth closed, with the upper teeth fully covering the mandibular teeth. On the upper jaw, there are five incisors, a gap of 0.8 centimeters, a canine (1.2 centimeters exposed, roughly 3.6 centimeters in total length), another 0.8 centimeter gap, and then five molars. After Owen removed the alveolar wall of the upper maxillary canine, he exposed the mandibular canine, which he found to be the same size as the maxillary. The semicircular canal found on ''A. felinus'' and all other gorgonopsians suggests that their heads were ventrally tilted, a characteristic of

predators Predation is a biological interaction where one organism, the predator, kills and eats another organism, its prey. It is one of a family of common feeding behaviours that includes parasitism and micropredation (which usually do not kill the ...

.Araújo, R., V. Fernandez, M. J. Polcyn, J. Fröbisch, R. M. S. Martins. 2017. Aspects of gorgonopsian paleobiology and evolution: insights from the basicranium, occiput, osseous labyrinth, vasculature, and neuroanatomy. PeerJ. (Vol. 5): 1–45. While Owen had originally assumed the holotype to be the skull of an adult, it has been argued that it was actually the skull of a juvenile. Owen only attributed its old age to the state of its sutures and teeth, while others noticed features indicating a young age, including its "...short snout, large orbits, slender postcanine teeth, tooth replacement, numerous small postcanine teeth, well developed foramina, large supraorbital portion of the frontal, anteriorly situated preparietal, slender skull arches, narrow vomer, well developed palatal tuberosities, teeth on transverse apophyses, large ectopterygoids, slender mandible, ndopen symphysis".

''A. whaitsi''

First described by Robert Broom in 1911. The holotype of ''A. whaitsi'' is another skull, but mostly snout, with the main indicator being a flatter symphysis. Its classification went back and forth throughout the entire century since it has very few defining features, all of which could be juvenile features of other genera.

''A. polyodon''

First described by Broom in 1935. The holotype of ''A.'' ''polyodon'' is a crushed snout. Originally named ''Galerhinus'' ''polyodon'', it was renamed ''Aelurosaurus'' ''polyodon'' in 1970.

''A. wilmanae''

First described by Broom in 1940. The holotype is a skull that is the best preserved of all the ''Aelurosaurus'' species. The defining feature is a larger snout compared to A. felinus, but overall the skull is still small at just 11 centimeters long.

''A.? watermeyeri''

First described by Broom in 1940. The holotype is a skull, and was originally named ''Scylacocephalus'' ''watermeyeri''. The genus is still under debate, since it shares features with both ''Aelurosaurus'' (such as a large orbit and short snout) and ''Aloposaurus'' (such as larger preparietal and postfrontal).

Geology/Paleoenvironment

''Aelurosaurus felinus'' was originally obtained in the Gough, of the Karoo Basin of South Africa, which includes the

Tapinocephalus ''Tapinocephalus'' ("humble head") is an extinct genus of large herbivorous dinocephalians that lived during the Middle Permian Period. These stocky, barrel-bodied animals were characterised by a massive bony skull roof and short weak snout. It i ...

and Pristerognathus Assemblage Zones.Boonstra, L.D. 1935. On the South African Gorgonopsian reptiles preserved in the American Museum of Natural History. ''American Museum Novitates''. 772: 1–14.Kammerer, C.F., R.M.H. Smith, M. O. Day, B.S. Rubidge. 2015. New information on the morphology and stratigraphic range of the mid-Permian gorgonopsian Eriphostoma microdon. Papers in Palaeontology. (Vol. 1) 2: 201–221. These assemblage zones are a part of the

Beaufort Group The Beaufort Group is the third of the main subdivisions of the Karoo Supergroup in South Africa. It is composed of a lower Adelaide Subgroup and an upper Tarkastad Subgroup. It follows conformably after the Ecca Group and unconformably underlie ...

and span from the Middle Perimian to the Late Permian.Angielczyk, K. D., B. S. Rubidge, M. O. Day, F. Lin. 2016. A reevaluation of Brachyprosopus broomi and Chelydontops altidentalis, dicynodonts (Therapsida, Anomodontia) from the middle Permian Tapinocephalus Assemblage Zone of the Karoo Basin, South Africa. Journal of Vertebrate Paleontology, (Vol. 36) 2. DOI: 10.1080/02724634.2016.1078342 The stratigraphic composition of the Beaufort Group include siltstone, mudstone, and sandstone beds, with evidence of rivers flowing across the land in semi-arid conditions. Findings of dense

coprolite A coprolite (also known as a coprolith) is fossilized feces. Coprolites are classified as trace fossils as opposed to body fossils, as they give evidence for the animal's behaviour (in this case, diet) rather than morphology. The name is de ...

s consisting of bones suggest that predators lived near these rivers.Smith, R. M. H., J. Botha-Brink. 2011. Morphology and composition of bone-bearing coprolites from the Late Permian Beaufort Group, Karoo Basin, South Africa. Palaeogeography, Palaeoclimatology, Palaeoecology (Vol. 312): 40–53. While most gorgonopsians have been recovered from the Karoo Basin in South Africa, there have been recent discoveries of gorgonopsians in Russia's Vyazniki Assemblage as well.Kammerer, C.F. 2016. On the evolutionary history of the Gorgonospia, with new information on their global first and last appearances. International Geological Congress. (Vol. 36): https://www.americangeosciences.org/sites/default/files/igc/4456.pdf

References

{{Taxonbar, from=Q1064130 Gorgonopsia Prehistoric therapsid genera Lopingian synapsids of Africa Fossil taxa described in 1881 Taxa named by Richard Owen Lopingian genus first appearances Lopingian genus extinctions Beaufort Group