Eotitanosuchus is an extinct genus of biarmosuchian therapsids whose fossils were found in the town of Ochyor in Perm Krai, Russia. It lived about 267 million years ago. The only species is Eotitanosuchus olsoni.
Biarmosuchia is an extinct clade of non-mammalian synapsids from the Permian. Biarmosuchians are the most basal group of the therapsids. They were moderately-sized, lightly-built carnivores, intermediate in form between basal sphenacodont "pelycosaurs" and more advanced therapsids. Biarmosuchians were rare components of Permian ecosystems, and the majority of species belong to the clade Burnetiamorpha, which are characterized by elaborate cranial ornamentation.
Therocephalia is an extinct suborder of eutheriodont therapsids from the Permian and Triassic. The therocephalians ("beast-heads") are named after their large skulls, which, along with the structure of their teeth, suggest that they were carnivores. Like other non-mammalian synapsids, therocephalians were once described as "mammal-like reptiles". Therocephalia is the group most closely related to the cynodonts, which gave rise to the mammals. This relationship takes evidence in a variety of skeletal features. The phylogeny of therocephalians has been disputed, as the monophyly of the group and the relationships of its members are unclear.
Charassognathus is an extinct genus of Late Permian cynodonts. Described in 2007 from a locality near Fraserburg, South Africa, Charassognathus is one of the earliest and most basal cynodonts. It is known only from the holotype, which dates from the Late Permian Period. The type and only species is C. gracilis. The holotype, found in the Tropidostoma Assemblage Zone of the Teekloof Formation, is made up of a crushed skull, partial lower jaw and one leg.
Viatkogorgon is a genus of gorgonopsian therapsid that lived during the Late Permian of what is now Russia.
Theriognathus is an extinct genus of therocephalian therapsid belonging to the family Whaitsiidae, known from fossils from South Africa, Zambia, and Tanzania. Theriognathus has been dated as existing during the Late Permian. Although Theriognathus means mammal jaw, the lower jaw is actually made up of several bones as seen in modern reptiles, in contrast to mammals. Theriognathus displayed many different reptilian and mammalian characteristics. For example, Theriognathus had canine teeth like mammals, and a secondary palate, multiple bones in the mandible, and a typical reptilian jaw joint, all characteristics of reptiles. It is speculated that Theriognathus was either carnivorous or omnivorous based on its teeth, and was suited to hunting small prey in undergrowth. This synapsid adopted a sleek profile of a mammalian predator, with a narrow snout and around 1 meter long. Theriognathus is represented by 56 specimens in the fossil record.
Bauriidae is an extinct family of therocephalian therapsids. Bauriids were the latest-surviving group of therocephalians after the Permian–Triassic extinction event, going extinct in the Middle Triassic. They are among the most advanced eutherocephalians and possess several mammal-like features such as a secondary palate and wide postcanine teeth at the back of the jaws. Unlike other therocephalians, bauriids were herbivorous. They were also smaller than earlier members of the group. Two subfamilies are classified within Bauriidae: Nothogomphodontinae and Bauriinae.
Gorochovetzia is an extinct genus of therocephalian therapsids from the Late Permian of Russia. Fossils have been found in the Gorokhovetsky District of Vladimir Oblast. Gorochovetzia is a member of the family Hofmeyriidae. Its type and only species is G. sennikovi, named in 2011. The skull is short and very robust. The canine teeth are large, while those behind them have enlarged crowns and serrated edges. The lower jaw is deep and curved upward.
Purlovia is an extinct genus of herbivorous therocephalian therapsids from the Late Permian of Russia. Together with the closely related South African genus Nanictidops, it is a member of the family Nanictidopidae. Fossils have been found from the Tonshayevsky District of Nizhny Novgorod Oblast. The type species of Purlovia, P. maxima, was named in 2011.
Muchia is an extinct genus of therocephalian therapsids from the Late Permian of Russia. Fossils have been found in the Kotelnichsky District of Kirov Oblast. The type species M. microdenta was named in 2011. Muchia is known only from a fragment of the lower jaw, making its classification among therocephalians uncertain. It is thought to be within the subfamily Tetracynodontinae, part of the larger group Baurioidea. Other members of the group such as Tetracynodon and Malasaurus are known from more complete material, and have small elongated skulls. Muchia probably had a similar appearance to these therocephalians.
Nanictidopidae is an extinct family of therocephalian therapsids from the Late Permian. Two genera are currently included in the family, Nanictidops from South Africa and Purlovia from Russia. Nanictidopids have short skulls and were probably herbivorous.
Choerosaurus is an extinct genus of therocephalian therapsids from the Late Permian of South Africa. The type species Choerosaurus dejageri was named by South African paleontologist Sidney H. Haughton from the Tropidostoma Assemblage Zone in 1929.
Blattoidealestes is an extinct genus of therocephalian therapsid from the Middle Permian of South Africa. The type species Blattoidealestes gracilis was named by South African paleontologist Lieuwe Dirk Boonstra from the Tapinocephalus Assemblage Zone in 1954. Dating back to the Middle Permian, Blattoidealestes is one of the oldest therocephalians. It is similar in appearance to the small therocephalian Perplexisaurus from Russia, and may be closely related.
Homodontosaurus is an extinct genus of therocephalian therapsids from the Late Permian of South Africa. The type species Homodontosaurus kitchingi was named by South African paleontologist Robert Broom in 1949. Broom based his description on a small skull found in the Cistecephalus Assemblage Zone near Graaff-Reinet. The skull is very small, at about 55 millimetres (2.2 in) long and 20 millimetres (0.79 in) wide. Homodontosaurus has large eye sockets and an elongated snout. The lower jaw is long, thin, and curved. Numerous small teeth line the upper jaw and are long, pointed, and round in cross-section.
Scalopodon is an extinct genus of therocephalian therapsids from the Late Permian of Russia. The type species Scalopodon tenuisfrons was named in 1999 from the Kotelnichsky District of Kirov Oblast. Scalopodon is known from a single fragmentary holotype specimen including the back of the skull, the left side of the lower jaw and isolated postorbital and prefrontal bones. The skull was found in the Deltavjatia Assemblage Zone, which dates back to the early Wuchiapingian about 260 million years ago. Distinguishing features of Scalopodon include narrow frontal bones and a distinctive sagittal crest along the parietal region at the back of the skull. Scalopodon was originally classified in the family Scaloposauridae, and was the first scaloposaurid found in Russia. More recent studies of therocephalians have found scaloposaurids like Scalopodon to be juvenile forms of larger therocephalians and do not consider Scaloposauridae to be a valid group. Scalopodon and most other scaloposaurids are now classified as basal members of Baurioidea.
Macroscelesaurus is an extinct genus of therocephalian therapsid from the Late Permian of South Africa. The type species Macroscelesaurus janseni was named by Sidney H. Haughton in 1918 from the Cistecephalus Assemblage Zone. It is one of the few therocephalians known from postcranial remains.
Karenites is an extinct genus of therocephalian therapsids from the Late Permian of Russia. The only species is Karenites ornamentatus, named in 1995. Several fossil specimens are known from the town of Kotelnich in Kirov Oblast.
Phthinosuchia is an extinct group of therapsids including two poorly known species, Phthinosuchus discors and Phthinosaurus borrisiaki, from the Middle Permian of Russia. Phthinthosuchus is known a partial crushed skull and Phthinosaurus is known from an isolated lower jaw. The two species have traditionally been grouped together based on their shared primitive characteristics, but more recent studies have proposed that they are more distantly related. Phthinosuchus is either a carnivorous gorgonopsian relative or an anteosaurian dinocephalian while Phthinosaurus is either a herbivorous rhopalodont dinocephalian or a therocephalian.
Gorgodon is an extinct genus of basal synapsids. The genus is monotypic, known only from the type species Gorgodon minutus from the Early Permian of the southwestern United States. The only known remains of Gorgodon are two fossils consisting of fragments of the skull. Gorgodon was described and named by paleontologist Everett C. Olson in 1962 from the San Angelo Formation in Knox County, Texas. Based on what is known of Gorgodon—the squamosal, quadrate, and pterygoid bones of the back of the skull, the maxilla and premaxilla bones that make up the front of the skull, and several teeth—Gorgodon had a relatively large temporal fenestra and a pair large, conical caniniform teeth at the front of the jaw. Other distinguishing features of Gorgodon include the fused connection between the quadrate and squamosal bones and a long transverse process of the pterygoid.
Parasumina is an extinct genus of anomodont known from the late Capitanian age at the end of the middle Permian period of European Russia. The type and only species is Parasuminia ivakhnekoi. It was closely related to Suminia, another Russian anomodont, and was named for its resemblance. Little is known about Parasuminia as the only fossils are of fragmentary pieces of the skull and jaw, but the known remains suggest that its head and jaws were deeper and more robust than those of Suminia, and with shorter, stouter teeth. However, despite these differences they appear to have been similar animals with a similarly complex method of processing vegetation.
