''Gorgonops'' (from 'Gorgon' and 'eye, face', literally '

Gorgon The Gorgons ( ; ), in Greek mythology, are three monstrous sisters, Stheno, Euryale, and Medusa, said to be the daughters of Phorcys and Ceto. They lived near their sisters the Graeae, and were able to turn anyone who looked at them to sto ...

eye' or 'Gorgon face') is an

extinct Extinction is the termination of an organism by the death of its Endling, last member. A taxon may become Functional extinction, functionally extinct before the death of its last member if it loses the capacity to Reproduction, reproduce and ...

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 ...

gorgonopsia Gorgonopsia (from the Greek Gorgon, a mythological beast, and 'aspect') is an extinct clade of Saber-toothed predator, sabre-toothed therapsids from the Middle Permian, Middle to the Upper Permian, roughly between 270 and 252 million years ago. ...

n therapsid, of which it is the

type genus In biological taxonomy, the type genus (''genus typica'') is the genus which defines a biological family and the root of the family name. Zoological nomenclature According to the International Code of Zoological Nomenclature, "The name-bearin ...

. ''Gorgonops'' lived during 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 ...

(

Wuchiapingian In the geologic timescale, the Wuchiapingian or Wujiapingian (from in the Liangshan area of Hanzhong, Shaanxi Province ) is an age or stage of the Permian. It is also the lower or earlier of two subdivisions of the Lopingian Epoch or S ...

), about 260–254 million years ago in what is now

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 ...

History of discovery

The

holotype A holotype (Latin: ''holotypus'') is a single physical example (or illustration) of an organism used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of s ...

of 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 ...

, ''Gorgonops torvus'', was one of the first therapsids discovered. It was described by

Richard Owen Sir Richard Owen (20 July 1804 – 18 December 1892) was an English biologist, comparative anatomy, comparative anatomist and paleontology, palaeontologist. Owen is generally considered to have been an outstanding naturalist with a remarkabl ...

, who also coined the name "Dinosauria" on the basis of the first known

dinosaur Dinosaurs are a diverse group of reptiles of the clade Dinosauria. They first appeared during the Triassic Geological period, period, between 243 and 233.23 million years ago (mya), although the exact origin and timing of the #Evolutio ...

fossil A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserve ...

s. ''G. torvus'' was also used as the type for the

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

Gorgonopsidae, which was described by

Richard Lydekker Richard Lydekker (; 25 July 1849 – 16 April 1915) was a British naturalist, geologist and writer of numerous books on natural history. He was known for his contributions to zoology, paleontology, and biogeography. He worked extensively in cata ...

in 1890. Five years later, in 1895,

Harry Govier Seeley Harry Govier Seeley (18 February 1839 – 8 January 1909) was a British paleontologist. Early life Seeley was born in London on 18 February 1839, the second son of Richard Hovill Seeley, a goldsmith, and his second wife Mary Govier. When his fa ...

used this genus to establish the larger clade of Gorgonopsia. In later years, a large number of further

species A species () is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. It is the basic unit of Taxonomy (biology), ...

and

genera Genus (; : genera ) is a taxonomic rank above species and below family as used in the biological classification of living and fossil organisms as well as viruses. In binomial nomenclature, the genus name forms the first part of the binomial s ...

were designated, though many of these were later determined to be synonyms. ''Gorgonops'' is known from the ''Tropidostoma'' and most of the ''Cistecephalus'' Assemblage Zones.

Description

''Gorgonops'' was a medium-sized gorgonopsian, with a skull length of , depending on the species. They ranged from long from nose to tail. ''Gorgonops'' would have been one of the key predators across southern Africa during the

. Because the canines were so large, they would have had little trouble in penetrating the tough hides of some of the herbivores of the time, particularly

pareiasaur Pareiasaurs (meaning "cheek lizards") are an extinct clade of large, herbivorous parareptiles. Members of the group were armoured with osteoderms which covered large areas of the body. They first appeared in southern Pangea during the Middle Per ...

s such as ''

Pareiasaurus ''Pareiasaurus'' (from , "cheek" and , "lizard") is an extinct genus of Pareiasauromorpha, pareiasauromorph reptile from the Permian period. It was a typical member of its family (biology), family, the pareiasaurids, which take their name from th ...

''. Aside from the teeth, one of the key predatory advantages that ''Gorgonops'' had over prey was its semi-erect gait, compared to the sprawling gait exhibited by most prey animals of the time. Aside from allowing for more energy efficient locomotion, this allowed ''Gorgonops'' to travel at relatively high speeds.

Skull

Relative to body size, ''Gorgonops'' had a deep skull with a triangular profile when viewed from above. Perhaps the most distinctive features were two enlarged canine teeth that were so big ( long) they almost protruded beyond the lower jaw. To help protect these teeth, the lower jaws grew in such a shape so that the anterior (front) portion was thicker than the posterior (rear) portion. This form would have protected the enlarged canine teeth from accidental damage, and was similar in bone function to the flanges of bone of sabre-toothed cats in the

Cenozoic The Cenozoic Era ( ; ) is Earth's current geological era, representing the last 66million years of Earth's history. It is characterized by the dominance of mammals, insects, birds and angiosperms (flowering plants). It is the latest of three g ...

Species

''Gorgonops torvus'' (Owen, 1876)

The type species. The holotype is an incomplete and flattened skull, allegedly found at Mildenhall's farm (Xlu Xlu), on the Queen's Road south of

Fort Beaufort Fort Beaufort ( Xhosa: iBhofolo), officially renamed KwaMaqoma in March 2023, is a town in the Amatole District of South Africa's Eastern Cape Province, and had a population of 25,668 in 2011. The town was established in 1837 and became a mun ...

, in the Eastern Cape of South Africa. A number of other specimens have been found since, all from the ''Tropidostoma'' and/or ''Cistecephalus'' Assemblage Zone(s). This was a medium-sized therapsid, with a skull about 22 cm in length. It is distinguished from other species by a longer snout, and other details of the bones of the skull. Originally considered rather simple, it is actually (according to Sigogneau-Russell) a rather specialised member of the group.

''Gorgonops whaitsi'' (Broom, 1912)

Larger than ''G. torvus'', with the rear of the skull wider, and other details of proportion. Originally the type species of ''Scymnognathus''. Despite being known from a large number of specimens from the

Karoo The Karoo ( ; from the Afrikaans borrowing of the South Khoekhoe Khoemana (also known as !Orakobab or Korana) word is a semidesert natural region of South Africa. No exact definition of what constitutes the Karoo is available, so its extent is ...

Basin, Beaufort West (''Tropidostoma''/''Cistecephalus'' Assemblage Zone), the species remains poorly known. Watson and

Romer Romer, Römer, Roemer, or similar may refer to: * Romer (surname), includes a list of people with the name * Romer (tool), a cartographic device also known as a reference card * Rømer scale, a disused temperature scale named after Ole Rømer * ...

placed ''Gorgonops'' and ''Scymnognathus'' in two different families, while Sigogneau-Russell placed the two species in the same genus, and considers ''G. whaitsi'' a more primitive (less derived) form. Synonyms: ''Scymnognathus whaitsi'' (Broom, 1912)

''Gorgonops longifrons'' (Haughton, 1915)

A large specimen known from an incomplete and flattened skull about long. Orbit larger and snout longer than ''G. whaitsi'', from which it may have descended.

Beaufort West Beaufort West (Afrikaans: ''Beaufort-Wes''; Xhosa: ''eBhobhofolo'') is a town in the Western Cape province in South Africa. It is the largest town in the arid Great Karoo region, and is known as the "Capital of the Karoo". It forms part of the ...

, ''Tropidostoma''/''Cistecephalus'' Assemblage Zone. Synonyms: ''Gorgonognathus longifrons'' (Haughton, 1915)

''Gorgonops? eupachygnathus'' (Watson, 1921)

A flattened, incomplete, medium-sized skull, probably a juvenile of either ''G. torvus'' or ''G. whaitsi'' Synonyms: ''Leptotrachelus eupachygnathus'' (Watson, 1921); ''Leptotracheliscops eupachygnathus'' (Watson, 1921)

''Gorgonops? dixeyi'' (Haughton, 1926)

A large, incomplete and flattened skull, from Chiweta Beds,

Nyassaland Nyasaland () was a British protectorate in Africa that was established in 1907 when the former British Central Africa Protectorate changed its name. Between 1953 and 1963, Nyasaland was part of the Federation of Rhodesia and Nyasaland. After ...

. Placement uncertain. Probably Low ''Cistecephalus'' Assemblage Zone equivalent (= middle of the

Stage). Synonyms: ''Chiwetasaurus dixeyi'' (Haughton, 1926)

''Gorgonops? kaiseri'' (Broili & Schroeder, 1934)

A large (about long), incomplete skull, with a high snout and narrower in the rear than other species, from the "High ''Tapinocephalus'' zone" (earlier than the other species, most probably ''Pristerognathus'' Assemblage Zone) Synonyms: ''Pachyrhinos kaiseri'' (Broili & Schroeder, 1934)

Classification

Below is a

cladogram A cladogram (from Greek language, Greek ''clados'' "branch" and ''gramma'' "character") is a diagram used in cladistics to show relations among organisms. A cladogram is not, however, an Phylogenetic tree, evolutionary tree because it does not s ...

from Gebauer's 2007 phylogenetic analysis.

References

{{Taxonbar, from=Q131690 Gorgonopsia Prehistoric therapsid genera Lopingian synapsids of Africa Fossil taxa described in 1876 Taxa named by Richard Owen Wuchiapingian genus first appearances Wuchiapingian genus extinctions