An anapsid is an amniote whose skull lacks one or more skull openings near the temples. Traditionally, the Anapsida are the most primitive subclass of amniotes, the ancestral stock from which Synapsida and Diapsida evolved, making anapsids paraphyletic. It is however doubtful that all anapsids lack temporal fenestra as a primitive trait, and that all the groups traditionally seen as anapsids truly lacked fenestra.
Mesosaurs were a group of small aquatic reptiles that lived during the early Permian period (Cisuralian), roughly 299 to 270 million years ago. Mesosaurs were the first known aquatic reptiles, having apparently returned to an aquatic lifestyle from more terrestrial ancestors. It is uncertain which and how many terrestrial traits these ancestors displayed; recent research cannot establish with confidence if the first amniotes were fully terrestrial, or only amphibious. Most authors consider mesosaurs to have been aquatic, although adult animals may have been amphibious, rather than completely aquatic, as indicated by their moderate skeletal adaptations to a semiaquatic lifestyle. Similarly, their affinities are uncertain; they may have been among the most basal sauropsids or among the most basal parareptiles.
Milleretta is an extinct genus of millerettid parareptile from the Late Permian of South Africa. Fossils have been found in the Balfour Formation. Milleretta was a moderately sized, lizard-like animal, about 60 centimetres (24 in) in length. It was probably insectivorous. Its only known species is Milleretta rubidgei, making Milleretta a monospecific genus.
Coelurosauravus is an extinct genus of gliding reptile, known from the Late Permian of Madagascar. Like other members of the family Weigeltisauridae, members of this genus possessed long, rod-like ossifications projecting outwards from the body. These bony rods were not extensions of the ribs but were instead a feature unique to weigeltisaurids. It is believed that during life, these structures formed folding wings used for gliding flight, similar to living gliding Draco lizards.
Claudiosaurus is an extinct genus of diapsid reptiles from the Late Permian Sakamena Formation of the Morondava Basin, Madagascar. It has been suggested to be semi-aquatic.
Hovasaurus is an extinct genus of basal diapsid reptile. It lived in what is now Madagascar during the Late Permian and Early Triassic, being a survivor of the Permian–Triassic extinction event and the paleontologically youngest member of the Tangasauridae. Fossils have been found in the Permian Lower and Triassic Middle Sakamena Formations of the Sakamena Group, where it is amongst the commonest fossils. Its morphology suggests an aquatic ecology.
Acerosodontosaurus is an extinct genus of neodiapsid reptiles that lived during the Upper Permian of Madagascar. The only species of Acerosodontosaurus, A. piveteaui, is known from a natural mold of a single partial skeleton including a crushed skull and part of the body and limbs. The fossil was discovered in deposits of the Lower Sakamena Formation. Based on skeletal characteristics, it has been suggested that Acerosodontosaurus individuals were at least partially aquatic.
Acleistorhinidae is an extinct family of Late Carboniferous and Early Permian-aged parareptiles. Acleistorhinids are most diverse from the Richards Spur locality of the Early Permian of Oklahoma. Richards Spur acleistorhinids include Acleistorhinus, Colobomycter, and possibly Delorhynchus and Feeserpeton. Other taxa include Carbonodraco from the Late Carboniferous of Ohio and Karutia from the Early Permian of Brazil. Acleistorhinidae is commonly considered a subgroup of lanthanosuchoids, related to taxa such as Chalcosaurus, Lanthaniscus and Lanthanosuchus. However, a re-examination of parareptile phylogeny conducted by Cisneros et al. (2021) argued that lanthanosuchids were not closely related to acleistorhinids. The phylogenetic analysis conducted by these authors recovered acleistorhinids as the sister group of the clade Procolophonia, while lanthanosuchids were recovered within the procolophonian subgroup Pareiasauromorpha.
Acleistorhinus (ah-kles-toe-RYE-nuss) is an extinct genus of parareptile known from the Early Permian of Oklahoma. It is notable for being the earliest known anapsid reptile yet discovered. The morphology of the lower temporal fenestra of the skull of Acleistorhinus bears a superficial resemblance to that seen in early synapsids, a result of convergent evolution. Only a single species, A. pteroticus, is known, and it is classified in the Family Acleistorhinidae, along with Colobomycter.
Owenetta is an extinct genus of owenettid procolophonian parareptile. Fossils have been found from the Beaufort Group in the Karoo Basin of South Africa. Although most procolophonians lived during the Triassic, Owenetta existed during the Wuchiapingian and Changhsingian stages of the Late Permian as well as the early Induan stage of the Early Triassic. It is the type genus of the family Owenettidae, and can be distinguished from other related taxa in that the posterior portion of the supratemporal bears a lateral notch and that the pineal foramen is surrounded by a depressed parietal surface on the skull table.
Owenettidae is an extinct family of procolophonian parareptiles. Fossils have been found primarily from Africa and Madagascar, with one genus present from South America. It is the sister taxon to the family Procolophonidae.
Procolophonoidea is an extinct superfamily of procolophonian parareptiles. Members were characteristically small, stocky, and lizard-like in appearance. Fossils have been found worldwide from many continents including Antarctica. The first members appeared during the Late Permian in the Karoo Basin of South Africa.
Microleter is an extinct genus of basal procolophonomorph parareptiles which lived in Oklahoma during the Early Permian period. The type and only known species is Microleter mckinzieorum. Microleter is one of several parareptile taxa described from the Richards Spur fissure fills, and can be characterized from its high tooth count, lacrimal/narial contact, short postfrontal, and slit-like temporal emargination edged by the postorbital, jugal, squamosal, and quadratojugal. Contrary to Australothyris, which had a similar phylogenetic position as a basal procolophonomorph, Microleter suggests that early parareptile evolution occurred in Laurasia and that multiple lineages developed openings or emarginations in the temporal region.
Coletta is an extinct genus of basal procolophonid parareptile from Early Triassic deposits of Eastern Cape Province, South Africa. It is known from the holotype GHG 228, a skull with fragmentary lower jaws. It was collected on the farm Brakfontein 333 in the Cradock District. It was found in the Katberg Formation of the Beaufort Group and referred to the Lystrosaurus Assemblage Zone. It was first named by Christopher E. Gow in 2000 and the type species is Coletta seca.
Ankyramorpha is an extinct clade of procolophonomorph parareptiles which lived between the early Cisuralian epoch and the latest Triassic period of Africa, Antarctica, Asia, Australia, Europe, North America and South America.
Lanthaniscus is an extinct genus of lanthanosuchoid ankyramorph parareptile known from the Guadalupian epoch of Eastern Europe, Russia. Lanthaniscus was first named by M. F. Ivakhnenko in 1980 and the type species is Lanthaniscus efremovi. L. efremovi was originally described on the basis of the holotype PIN 3706/9 from Peza-1 locality, Krasnoshchel' Formation, of Arkhangelsk. Various authors had assigned it to the family Lanthanosuchidae; however, Ivakhnenko, who described an additional specimen of L. efremovi in 2008, assigned Lanthaniscus to its own family, the Lanthaniscidae. The additional specimen PIN 4543/2, was collected from the same formation as the holotype, from the Nisogora locality, which is slightly younger in age.
Anomoiodon is an extinct genus of procolophonine procolophonid parareptile from early Triassic deposits of Thuringia, Germany. It is known only from the holotype MB.R.3539B and paratype MB.R.3539A, two articulated, three-dimensionally preserved partial skeletons on one block which represent two individuals. The holotype includes nearly complete skull and lower jaw. The block was collected from the lowest layer of the Chirotherium Sandstone Member of the Solling Formation, dating to the early Olenekian faunal stage of the Early Triassic, about 249-247 million years ago. It was first named by Friedrich von Huene in 1939 and the type species is Anomoiodon liliensterni. Laura K. Säilä, who redescribed Anomoiodon in 2008, found it to be a leptopleuronine using a phylogenetic analysis. The most recent analysis, performed by Ruta et al. (2011) found it to be a procolophonine instead. However, both analyses found that it is most closely related to the Russian procolophonid Kapes.
Tangasaurus is an extinct genus of aquatic basal tangasaurid neodiapsid known from the Late Permian period of Tanga, northeastern Tanzania. It contains a single species, Tangasaurus mennelli.
Ruhuhuaria is an extinct genus of owenettid procolophonoid reptile known from the Middle Triassic Manda Beds of southwestern Tanzania. Ruhuhuaria is known solely from the holotype CAMZM T997, poorly preserved but complete skull and mandible recently re-discovered in the collections of the Cambridge Museum of Zoology. It was collected by the English paleontologist Francis Rex Parrington in the early 1930s from the Lifua Member of Manda Beds of the Ruhuhu Basin in Songea Urban District of southwestern Tanzania, which dates back to the late Anisian stage of the Middle Triassic. Ruhuhuaria was first described and named by Linda Akiko Tsuji, Gabriela Sobral and Johannes Müller in 2013 and the type species is Ruhuhuaria reiszi. The generic name is derived from the name of the Ruhuhu Basin. The specific name, reiszi, honors the Canadian paleontologist Robert R. Reisz. Due to the poor preservation of the holotype, the phylogenetic position of Ruhuhuaria within Owenettidae is uncertain. Ruhuhuaria being the second youngest owenettid to date, supports the persistence of owenettids into the Middle Triassic and their coexistence with procolophonids.
Saurodektes is an extinct genus of owenettid procolophonoid parareptile known from the earliest Triassic deposits of Eastern Cape Province, South Africa. It was first named by Sean P. Modesto, Ross J. Damiani, Johann Neveling and Adam M. Yates in 2003 and the type species is Saurodectes rogersorum. The generic name Saurodectes was preoccupied by the generic name of Saurodectes vrsanskyi Rasnitsyn & Zherikhin, 2000, a fossil chewing lice known from the Early Cretaceous of Russia. Thus, an alternative generic name, Saurodektes, was proposed by Modesto et al. in 2004. The generic name means "lizard", sauros, and "biter", dektes from Greek. The specific name, rogersorum, honors Richard and Jenny Rogers, owners of the farm Barendskraal, for their hospitality, support and interest in the work of the paleontologists who recovered the holotype. Saurodektes is known solely from the holotype BP/1/6025, a partial skull and some fragmentary partial postcranial elements, housed at the Bernard Price Institute for Palaeontological Research, although the unprepared specimens BP/1/6044, BP/1/6045 and BP/1/6047 might also be referable to it. All specimens were collected on the slopes of the Manhaar Hill at Barendskraal in the Middelburg District, from the Palingkloof Member of the Balfour Formation, Beaufort Group, only 12 metres below the base of the Katberg Formation. This horizon belongs to the Lystrosaurus Assemblage Zone, dating to the early Induan stage of the Early Triassic period.
