| Lycideopidae Temporal range: Late Permian - Early Triassic | |
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Scientific classification  | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Clade: | Synapsida |
| Clade: | Therapsida |
| Clade: | † Therocephalia |
| Superfamily: | † Baurioidea |
| Family: | † Lycideopidae Boonstra, 1934 |
| Genera | |
Lycideopidae is an extinct family of therocephalians from the Late Permian and Early Triassic of South Africa.
Below is a cladogram from Sigurdsen et al. (2012): [1]
| Therapsida |
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Therocephalia is an extinct clade 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.
Eutherocephalia is an extinct clade of advanced therocephalian therapsids. Eutherocephalians are distinguished from the lycosuchids and scylacosaurids, two early therocephalian families. While lycosuchids and scyalosaurids became extinct by the end of the Permian period, eutherocephalians survived the Permian–Triassic extinction event. The group eventually became extinct in the Middle Triassic.
Euchambersia is an extinct genus of therocephalian therapsids that lived during the Late Permian in what is now South Africa and China. The genus contains two species. The type species E. mirabilis was named by paleontologist Robert Broom in 1931 from a skull missing the lower jaw. A second skull, belonging to a probably immature individual, was later described. In 2022, a second species, E. liuyudongi, was named by Jun Liu and Fernando Abdala from a well-preserved skull. It is a member of the family Akidnognathidae, which historically has also been referred by as the synonymous Euchambersiidae.
Moschorhinus is an extinct genus of therocephalian synapsid in the family Akidnognathidae with only one species: M. kitchingi, which has been found in the Late Permian to Early Triassic of the South African Karoo Supergroup. It was a large carnivorous therapsid, reaching 1.5 m (4.9 ft) in total body length with the largest skull comparable to that of a lion in size, and had a broad, blunt snout which bore long, straight canines.
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.
Moschowhaitsia is an extinct genus of therocephalian therapsids from the Late Permian (Guadalupian) of Russia and China. The type species, Moschowhaitsia vjuschkovi, was discovered in the Changxingian-aged Archosaurus Assemblage Zone of Russia and named in 1963 by Russian palaeontologist Leonid Petrovich Tatarinov. A second species was discovered in Jingtai County of Gansu, China in 2020 and named as M. lidaqingi in 2023 by Jun Liu and Fernando Abdala, the first whaitsiid therocephalian to be discovered in China. It was among the larger carnivores in the faunal assemblages it occurred in, with a skull-length of up to 25 centimetres (9.8 in) in M. vjuschkovi and an even larger estimated 35 centimetres (14 in) for M. lidaqingi, one of the largest therocephalian skulls reported. The genus name Moschowhaitsia alludes to two other therocephalians, Moschorhinus and Whaitsia, due to the structure of its palate combining physical features of both these genera.
Tetracynodon is an extinct genus of therocephalian. Fossils of Tetracynodon have been found in the Karoo Basin of South Africa. Two species are known: the type species T. tenuis from the Late Permian and the species T. darti from the Early Triassic. Both species were small-bodied and probably fed on insects and small vertebrates. Although Tetracynodon is more closely related to mammals than to reptiles, its braincase is very primitive and more resembles that of modern amphibians and reptiles than of mammals.
Baurioidea is a superfamily of therocephalian therapsids. It includes advanced therocephalians such as Regisaurus and Bauria. The superfamily was named by South African paleontologist Robert Broom in 1911. Bauriamorpha, named by D. M. S. Watson and Alfred Romer in 1956, is a junior synonym of Baurioidea.
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.
Silpholestes is an extinct genus of therocephalian therapsids from the Late Permian of South Africa. The type species Silpholestes jackae was named by South African paleontologist Robert Broom in 1948 from the Cistecephalus Assemblage Zone.
Ictidodraco is an extinct genus of therocephalian therapsids from the Late Permian of South Africa. The type species Ictidodraco longiceps was named by South African paleontologists Robert Broom and John T. Robinson in 1948 from the Cistecephalus Assemblage Zone. Ictidodraco was once classified as a scaloposaurian in the family Silpholestidae. Scaloposauria and Silpholestidae are no longer regarded as valid groups, and Ictidodraco is now classified as a basal member of the clade 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.
Polycynodon is an extinct genus of therocephalians from the Late Permian of South Africa. It is known from the Cistecephalus Assemblage Zone. The type species was first described as Octocynodon elegans by South African paleontologist Robert Broom in 1940, but the name Octocynodon was preoccupied by a genus of labrid fish first described in 1904. Along with John T. Robinson, Broom instated Polycynodon as a replacement name for O. elegans in 1948. Polycynodon is classified in Baurioidea, although its relationship to other baurioid therocephalians is uncertain.
Pelictosuchus is an extinct genus of therocephalian therapsids from the Late Permian of South Africa. It is classified in the family Akidnognathidae. The type species Pelictosuchus paucidens was named by South African paleontologist Robert Broom in 1940 from the Dicynodon Assemblage Zone.
Eutheriodontia is a clade of therapsids which appear during the Middle Permian and which includes therocephalians and cynodonts, this latter group including mammals and related forms.
Lycideops is an extinct genus of therocephalians from the Late Permian of South Africa. The type species is Lycideops longiceps, named in 1931 by South African paleontologist Robert Broom. Fossils of Lycideops come from the Dicynodon Assemblage Zone of the Beaufort Group. Lycideops is a member of the family Lycideopidae. Like other lycideopids, Lycideops has a long snout.
Urumchia is an extinct genus of therocephalian therapsids from the Early Triassic of China. The type species Urumchia lii was described by Chinese paleontologist C. C. Young in 1952 from the Jiucaiyuan Formation in Xinjiang. The holotype skull has been lost, but Young was able to describe the species on the basis of a detailed cast of the skull. Urumchia is similar to the South African therocephalian Regisaurus in having an expanded pair of vomer bones on the underside of the skull that form a secondary palate. In Urumchia the front end of the vomers narrow to a point, while in Regisaurus they do not. Urumchia has six incisors on either side of the upper jaw, a primitive condition among baurioid therocephalians that usually have fewer incisors.
Simorhinella is an extinct genus of therocephalian therapsids from the Late Permian of South Africa. It is known from a single species, Simorhinella baini, named by South African paleontologist Robert Broom in 1915. Broom named it on the basis of a single fossil collected by the British Museum of Natural History in 1878 that included the skull and jaws forward from the eye sockets. The skull is unusual in that it has an extremely short and deep snout, unlike the longer and lower snouts of most other therocephalians. Because of the skull's distinctiveness, the classification of Simorhinella within Therocephalia is uncertain. However, a 2014 study proposed that it was closely related to the basal therocephalian Lycosuchus, placing it in the family Lycosuchidae.
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