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.
Dissorophidae is an extinct family of medium-sized, temnospondyl amphibians that flourished during the late Carboniferous and early Permian periods. The clade is known almost exclusively from North America.
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.
Microsauria is an extinct, possibly polyphyletic order of tetrapods from the late Carboniferous and early Permian periods. It is the most diverse and species-rich group of lepospondyls. Recently, Microsauria has been considered paraphyletic, as several other non-microsaur lepospondyl groups such as Lysorophia seem to be nested in it. Microsauria is now commonly used as a collective term for the grade of lepospondyls that were originally classified as members of Microsauria.
Araeoscelidia or Araeoscelida is a clade of extinct diapsid reptiles superficially resembling lizards, extending from the Late Carboniferous to the Early Permian. The group contains the genera Araeoscelis, Petrolacosaurus, the possibly aquatic Spinoaequalis, and less well-known genera such as Kadaliosaurus and Zarcasaurus. This clade is considered to be the sister group to all later diapsids.
The Chroniosuchidae are a family of semi-aquatic reptiliomorph amphibians found in sediments from the upper Permian and the upper Triassic periods, most in Russia. They were generally rather large animals, with long jaws similar to those found in modern crocodiles, and probably lived a similar life style as riverside piscivores and ambush predators. Like all Chroniosuchians, they bore extensive osteoderm armour on their backs, possibly as protection against terrestrial predators such as the Permian therapsids and the Triassic Rauisuchians.
Burnetiidae is an extinct family of biarmosuchian therapsids that lived in the Permian period of South Africa and Russia. It contains Bullacephalus, Burnetia, Mobaceras, Niuksenitia, Paraburnetia and Proburnetia.
Nigerpeton is a genus of temnospondyl amphibian which lived during the Permian period some 250 million years ago in Niger. Specimens of Nigerpeton were first collected during field work in the Moradi Formation in 2000 and 2003.
Pachydectes is an extinct genus of biarmosuchian therapsids from the Middle Permian of South Africa.
Tupilakosauridae is an extinct family of dvinosaurian temnospondyls. It contains the genera Slaugenhopia, Thabanchuia, Tupilakosaurus, and possibly Kourerpeton. Tupilakosaurs are known from Texas, Greenland, Russia, and France. The earliest tupilakosaur, Slaugenhopia, is Early Permian in age while the latest known tupilakosaurs are Early Triassic in age. Derived tupilakosaurs possess embolomerous centra in their vertebrae, which are diplospondylous. They also have a deep notch in the pterygoid bone of the palate. Tupilakosaurs were aquatic, and used an undulatory mode of swimming much like that of eels.
Idelesaurus is a genus of dicynodont from the Late Permian (Wuchiapingian) Ilinskoe Subassemblage of the Sokolki Assemblage Zone of Russia.
Chlynovia is an extinct genus of therocephalian therapsids from the Late Permian of Russia. The type species is C. serridentatus, named in 2000. Chlynovia was originally classified within Scaloposauria, a group of therocephalians characterized by their small size and lightly built skulls. Scaloposaurians are no longer recognized as a true grouping, but instead represent the juvenile forms of many types of therocephalians. Chlynovia was placed in the family Perplexisauridae along with Perplexisaurus, but both therocephalians are now placed in the family Ictidosuchidae.
Pasawioops is an extinct genus of early Permian dissorophoid temnospondyl within the clade Amphibamiformes.
Rubeostratilia is an extinct genus of amphibamiform temnospondyl from the early Permian of Texas. It is known from a single skull. This genus was named by Hélène Bourget and Jason S. Anderson in 2011, and the type species is Rubeostratilia texensis. The genus name comes from the Latin translation of 'redbeds' in reference to the Texas redbeds that produced both the holotype and many other early Permian fossils. The species name is for the state of Texas. The holotype and only known specimen was collected in 1941 from the Nocona Formation exposures in Clay County by a Works Projects Administration project that was transferred to the Field Museum of Natural History through an interinstitutional exchange with the Texas Memorial Museum.
Georgenthalia is an extinct genus of dissorophoid temnospondyl from the Lower Permian. It is an amphibamid which lived in what is now the Thuringian Forest of central Germany. It is known from the holotype MNG 11135, a small, complete skull. It was found in the Bromacker locality of the Tambach Formation. It was first named by Jason S. Anderson, Amy C. Henrici, Stuart S. Sumida, Thomas Martens and David S. Berman in 2008 and the type species is Georgenthalia clavinasica.
Plemmyradytes is an extinct genus of dissorophoid temnospondyl from the early Permian. It is an amphibamiform from the Eskridge Formation exposures of Nebraska. The type species is Plemmyradytes shintoni. The genus name derives from the Greek plemmyris and dytes ('diver'), while the species name honors John Shinton, a fossil preparator at the Denver Museum of Natural History where all known specimens of this taxon are reposited following collection in the late 20th century.
Elph is an extinct genus of dicynodont therapsids from Russia. Four specimens have been found from the Sokolki Assemblage in European Russia, representing a fauna that dates back to the Late Permian. Elph was a small herbivore that lived alongside carnivorous akidnognathids and inostranceviids, as well as larger herbivores like Dicynodon and pareiasaurids. The type species E. borealis was named in 1999. Elph has a short snout and tusks and is closely related to Interpresosaurus and Katumbia.
Olsoniformes is a clade of dissorophoid temnospondyls. It includes the families Dissorophidae and Trematopidae. Most members of the clade were highly adapted to a terrestrial lifestyle. The clade was named in 2008 and is defined as the least inclusive clade containing Dissorophus multicinctus and Acheloma cumminsi but not Amphibamus grandiceps, Micromelerpeton credneri, and Apateon pedestris. Olsoniforms share various features such as a stout and low ilium and a thin cultriform process.
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.
