Therapsida is a major group of eupelycosaurian synapsids that includes mammals and their ancestors. Many of the traits today seen as unique to mammals had their origin within early therapsids, including limbs that were oriented more underneath the body, as opposed to the sprawling posture of many reptiles and salamanders. The earliest fossil attributed to Therapsida used to be Tetraceratops insignis from the Lower Permian. However in 2020, a new study has found that Tetraceratops is not actually a true Therapsid, but should be considered to be a member of the more ancient Sphenacodontia from which the therapsids evolved.
Camelids are members of the biological family Camelidae, the only currently living family in the suborder Tylopoda. The extant members of this group are: dromedary camels, Bactrian camels, wild Bactrian camels, llamas, alpacas, vicuñas, and guanacos. Camelids are even-toed ungulates classified in the order Cetartiodactyla, along with pigs, whales, deer, cattle, antelope, and many others.
Dicynodontia is a taxon of anomodont therapsids with beginnings in the mid-Permian, which were dominant in the Late Permian, survived the Permian Extinction that wiped out most other therapsids and continued on throughout the Triassic before dying out at the end of the period. Dicynodonts were herbivorous animals with two tusks, hence their name, which means 'two dog tooth'. They are also the most successful and diverse of the non-mammalian therapsids, with over 70 genera known, varying from rat- to elephant-sized.
Megalonychidae is a group of sloths including the extinct Megalonyx. Megalonychids first appeared in the early Oligocene, about 35 million years (Ma) ago, in southern Argentina (Patagonia). There is actually one possible find dating to the Eocene, about 40 Ma ago, on Seymour Island in Antarctica. They first reached North America by island-hopping across the Central American Seaway, about 9 million years ago, prior to formation of the Isthmus of Panama about 2.7 million years ago. Some megalonychid lineages increased in size as time passed. The first species of these were small and may have been partly tree-dwelling, whereas the Pliocene species were already approximately half the size of the huge Late Pleistocene Megalonyx jeffersonii from the last ice age.
The Tropidostoma Assemblage Zone is a tetrapod assemblage zone or biozone which correlates to the lower Teekloof Formation, Adelaide Subgroup of the Beaufort Group, a fossiliferous and geologically important geological Group of the Karoo Supergroup in South Africa. The thickest outcrops, reaching approximately 240 metres (790 ft), occur from east of Sutherland through to Beaufort West and Victoria West, to areas south of Graaff-Reinet. Its northernmost exposures occur west/north-west of Colesberg. The Tropidostoma Assemblage Zone is the fourth biozone of the Beaufort Group.
Ailuravus is a genus of prehistoric rodents in the family Ischyromyidae.
Scapanus is a genus of moles in the family Talpidae. They live in North America from west of the Rockies south to Baja California del Norte, and north to British Columbia, wherever conditions permit a mole population; that is to say, apart from the most sandy, rocky, or developed places. As they are one genus, they are very closely related, but as species, they rarely if ever interbreed successfully.
Myosaurus is an extinct genus of dicynodont found primarily in Antarctica and South Africa.
Eosimops is an extinct genus of pylaecephalid dicynodonts. They were small synapsids superficially resembling modern mammals. Eosimops is known from several skull specimens, as well as one complete skeleton. Eosimops lived during the Middle Permian of South Africa.
The Neotherapsida are a clade of therapsids. The clade includes anomodonts and the more derived theriodonts, which include mammals.
Pylaecephalidae is a family of dicynodont therapsids that includes Diictodon, Robertia, and Prosictodon from the Permian of South Africa. Pylaecephalids were small burrowing dicynodonts with long tusks. The family was first named in 1934 and was redefined in 2009. Diictodontidae and Robertiidae are considered junior synonyms of Pylaecephalidae.
Emydopidae is a family of dicynodont therapsids.
Emydopoidea is a group of Late Permian dicynodont therapsids. It includes the small-bodied Emydops, Myosaurus, and kingoriids, and the burrowing cistecephalids. Below is a cladogram from Kammerer et al. (2011) showing the phylogenetic relationships of emydopoids:
The Nuussuaq Group is a geologic group in Greenland. It preserves fossils dating back to the Paleogene period.
The Normandien Formation is a Triassic-age rock formation located in Free State, South Africa. It is where the fossils of Ericiolacerta, a subtaxa of Ericiolacertidae, was found.
Thliptosaurus is an extinct genus of small kingoriid dicynodont from the latest Permian period of the Karoo Basin in KwaZulu-Natal, South Africa. It contains the type and only known species T. imperforatus. Thliptosaurus is from the upper Daptocephalus Assemblage Zone, making it one of the youngest Permian dicynodonts known, living just prior to the Permian mass extinction. It also represents one of the few small bodied dicynodonts to exist at this time, when most other dicynodonts had large body sizes and many small dicynodonts had gone extinct. The unexpected discovery of Thliptosaurus in a region of the Karoo outside of the historically sampled localities suggests that it may have been part of an endemic local fauna not found in these historic sites. Such under-sampled localities may contain 'hidden diversities' of Permian faunas that are unknown from traditional samples. Thliptosaurus is also unusual for dicynodonts as it lacks a pineal foramen, suggesting that it played a much less important role in thermoregulation than it did for other dicynodonts.
Myosaurus , an Emydopid
A Diictodon fossil
