''Dinogorgon'' is a

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 ...

of gorgonopsid 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 ...

and

Tanzania Tanzania, officially the United Republic of Tanzania, is a country in East Africa within the African Great Lakes region. It is bordered by Uganda to the northwest; Kenya to the northeast; the Indian Ocean to the east; Mozambique and Malawi to t ...

. The generic name ''Dinogorgon'' is derived from Greek, meaning "terrible

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 ...

", while its species name ''rubidgei'' is taken from the surname of renowned

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 ...

paleontologist, Professor Bruce Rubidge, who has contributed to much of the research conducted on therapsids of the Karoo Basin. 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 ...

of the genus is ''D. rubidgei''. ''Dinogorgon'' is part of the

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. ...

subfamily In biological classification, a subfamily (Latin: ', plural ') is an auxiliary (intermediate) taxonomic rank, next below family but more inclusive than genus. Standard nomenclature rules end botanical subfamily names with "-oideae", and zo ...

Rubidgeinae, a derived group of large-bodied gorgonopsians restricted to the Late

Permian The Permian ( ) is a geologic period and System (stratigraphy), stratigraphic system which spans 47 million years, from the end of the Carboniferous Period million years ago (Mya), to the beginning of the Triassic Period 251.902 Mya. It is the s ...

(

Lopingian The Lopingian is the uppermost series/last epoch of the Permian. It is the last epoch of the Paleozoic. The Lopingian was preceded by the Guadalupian and followed by the Early Triassic. The Lopingian is often synonymous with the informal te ...

). The Rubidgeinae subfamily first appeared in the ''Tropidostoma'' Assemblage Zone, and reached their highest diversity in the '' Cistecephalus'' and '' Daptocephalus'' assemblage zones of the Beaufort Group in

History of discovery

The type specimen of ''Dinogorgon rubidgei'' was discovered on Wellwood farm, a farm owned by the grandfather of Bruce Rubidge, Sidney H. Rubidge, outside of

Graaff-Reinet Graaff-Reinet (; Xhosa: eRhafu) is a town in the Eastern Cape Province of South Africa. It is the oldest town in the province and the fourth oldest town in South Africa, after Cape Town, Stellenbosch, Simon's Town, Paarl and Swellendam. The to ...

. The fossil was likely recovered by Haughton himself sometime in the 1930s or 1940s, and were only described by British paleontologist, Sidney H. Haughton, and James Kitching between 1953 and 1965.

Description

''Dinogorgon'' was one of the largest species of Rubidgeinae, with the skull length of nearly , almost as large as '' Rubidgea'' had. It was a formidable predator, and likely preyed on

reptile Reptiles, as commonly defined, are a group of tetrapods with an ectothermic metabolism and Amniotic egg, amniotic development. Living traditional reptiles comprise four Order (biology), orders: Testudines, Crocodilia, Squamata, and Rhynchocepha ...

s and smaller therapsids. Like more derived rubidgeines, ''Dinogorgon'' had a number of bosses on its skull, likely to reduce the stresses caused by struggling prey. Its snout was deep but narrow, similar to '' Aelurognathus'', but narrower than ''Rubidgea'' and '' Clelandina''. It had 4 to 5 upper and lower postcanine teeth, which further distinguishes it from '' Rubidgea''. Three

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), ...

were recognized in the genus ‒ ''D. rubidgei'', ''D. quinquemolaris'', and ''D. pricei'' ‒ but these are now all considered to be ''D. rubidgei''.

Classification

The Rubidgeinae are a

of derived gorgonopsids that have only been found in

Africa Africa is the world's second-largest and second-most populous continent after Asia. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 20% of Earth's land area and 6% of its total surfac ...

. They are composed of six

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 ...

and 17

. The Rubidgeinae are closely related to their sister group, the Inostranceviinae, which have only been found in

Russia Russia, or the Russian Federation, is a country spanning Eastern Europe and North Asia. It is the list of countries and dependencies by area, largest country in the world, and extends across Time in Russia, eleven time zones, sharing Borders ...

. Out of the

clade In biology, a clade (), also known as a Monophyly, monophyletic group or natural group, is a group of organisms that is composed of a common ancestor and all of its descendants. Clades are the fundamental unit of cladistics, a modern approach t ...

, the

systematics Systematics is the study of the diversification of living forms, both past and present, and the relationships among living things through time. Relationships are visualized as evolutionary trees (synonyms: phylogenetic trees, phylogenies). Phy ...

of the Rubidgeinae are the best resolved due to their distinctive character traits. The

of other

n subfamilies remain chaotic due to a high degree of

cranial Standard anatomical terms of location are used to describe unambiguously the anatomy of humans and other animals. The terms, typically derived from Latin or Greek language, Greek roots, describe something in its standard anatomical position. Thi ...

homomorphism between

taxa In biology, a taxon (back-formation from ''taxonomy''; : taxa) is a group of one or more populations of an organism or organisms seen by taxonomists to form a unit. Although neither is required, a taxon is usually known by a particular name and ...

, making it difficult to distinguish different

effectively. ''Dinogorgon'' shares many characteristics with '' Rubidgea'' and '' Clelandina'', which has led some authors to synonymize them. All three are now considered to be part of the same

tribe The term tribe is used in many different contexts to refer to a category of human social group. The predominant worldwide use of the term in English is in the discipline of anthropology. The definition is contested, in part due to conflict ...

, Rubidgeini, rather than the same

. The

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 ...

below (Kammerer et al. 2016) displays currently accepted systematic relationships of the

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. ...

Palaeoenvironment

Numerous therapsid

, including rubidgenine gorgonopsids, are used as biostratigraphic markers in other African basins, such as the Upper Madumabisa Mudstone of

Zambia Zambia, officially the Republic of Zambia, is a landlocked country at the crossroads of Central Africa, Central, Southern Africa, Southern and East Africa. It is typically referred to being in South-Central Africa or Southern Africa. It is bor ...

, the Usili Formation of

, and the Chiweta Beds of

Malawi Malawi, officially the Republic of Malawi, is a landlocked country in Southeastern Africa. It is bordered by Zambia to the west, Tanzania to the north and northeast, and Mozambique to the east, south, and southwest. Malawi spans over and ...

References

{{Taxonbar, from=Q280846 Gorgonopsia Prehistoric therapsid genera Lopingian synapsids of Africa Lopingian genus first appearances Lopingian genus extinctions Permian South Africa Fossils of South Africa Fossils of Tanzania Fossils of Zambia Fossil taxa described in 1936 Taxa named by Robert Broom