An anapsid is an amniote whose skull lacks one or more skull openings near the temples. Traditionally, the Anapsida are considered 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.
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.
Procolophonia is an extinct suborder (clade) of herbivorous reptiles that lived from the Middle Permian till the end of the Triassic period. They were originally included as a suborder of the Cotylosauria but are now considered a clade of Parareptilia. They are closely related to other generally lizard-like Permian reptiles such as the Millerettidae, Bolosauridae, Acleistorhinidae, and Lanthanosuchidae, all of which are included under the Anapsida or "Parareptiles".
Procolophonomorpha is an order or clade containing most parareptiles. Many papers have applied various definitions to the name, though most of these definitions have since been considered synonymous with modern parareptile clades such as Ankyramorpha and Procolophonia. The current definition of Procolophonomorpha, as defined by Modesto, Scott, & Reisz (2009), is that of as a stem-based group containing Procolophon and all taxa more closely related to it than to Milleretta. It constitutes a diverse assemblage that includes a number of lizard-like forms, as well as more diverse types such as the pareiasaurs. Lee 1995, 1996, 1997 argues that turtles evolved from pareiasaurs, but this view is no longer considered likely. Rieppel and deBraga 1996 and deBraga and Rieppel, 1997 argue that turtles evolved from sauropterygians, and there is both molecular and fossil (Pappochelys) evidence for the origin of turtles among diapsid reptiles.
The Lystrosaurus Assemblage Zone is a tetrapod assemblage zone or biozone which correlates to the upper Adelaide and lower Tarkastad Subgroups of the Beaufort Group, a fossiliferous and geologically important geological Group of the Karoo Supergroup in South Africa. This biozone has outcrops in the south central Eastern Cape and in the southern and northeastern Free State. The Lystrosaurus Assemblage Zone is one of eight biozones found in the Beaufort Group, and is considered to be Early Triassic in age.
Procolophonidae is an extinct family of small, lizard-like parareptiles known from the Late Permian to Late Triassic that were distributed across Pangaea, having been reported from Europe, North America, China, South Africa, South America, Antarctica and Australia. The most primitive procolophonids were likely insectivorous or omnivorous, more derived members of the clade developed bicusped molars, and were likely herbivorous feeding on high fiber vegetation or durophagous omnivores. Many members of the group are noted for spines projecting from the quadratojugal bone of the skull, which likely served a defensive purpose as well as possibly also for display. At least some taxa were likely fossorial burrowers. While diverse during the Early and Middle Triassic, they had very low diversity during the Late Triassic, and were extinct by the beginning of the Jurassic.
Procolophon is a genus of lizard-like procolophonid parareptiles that first appeared in the Early Triassic (Induan) of South Africa, Brazil, and Antarctica. It persisted through the Permian–Triassic extinction event, but went extinct in the beginning of the Early Middle Triassic. The type species is P. trigoniceps.
Colobomycter is an extinct genus of acleistorhinid parareptile known from the Early Permian of Oklahoma.
Acleistorhinidae is an extinct family of Late Carboniferous and Early Permian-aged parareptiles. It is defined as a node based clade including the last common ancestor of Acleistorhinus pteroticus and Colobomycter pholeter and all its descendants. 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. Modesto and Damiani (2007) defined Owenettidae as a stem-based group including Owenetta rubidgei and all species closely related to it than to Procolophon trigoniceps.
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.
Sauropareion is an extinct genus of basal procolophonid parareptile from earliest Triassic deposits of Eastern Cape Province, South Africa. It is known from the holotype SAM PK-11192, skull and partial postcranium. It was collected by the late L. D. Boonstra in 1935 from Barendskraal in the Middelburg District and referred to the Lystrosaurus Assemblage Zone of the Beaufort Group. It was first named by Sean P. Modesto, Hans-Dieter Sues and Ross J. Damiani in 2001 and the type species is Sauropareion anoplus. The generic name means "lizard", sauros, and "cheek", pareion from Greek in reference to the lizard-like appearance of the temporal region. The specific name comes from the Greek word anoplos, meaning "without arms or armour".
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.
Lanthanosuchoidea is an extinct superfamily of ankyramorph parareptiles from the middle Pennsylvanian to the middle Guadalupian epoch of Europe, North America and Asia. It was named by the Russian paleontologist Ivachnenko in 1980, and it contains two families Acleistorhinidae and Lanthanosuchidae.
Nyctiphruretidae is an extinct family of hallucicranian parareptiles known from the late Early to the late Middle Permian of European Russia and south-central United States.
Barasaurus is an extinct genus of owenettid procolophonoid parareptile known from the Late Permian and Early Triassic of Madagascar. It contains a single species, Barasaurus besairiei.
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.
