Archosauromorpha is a clade of diapsid reptiles containing all reptiles more closely related to archosaurs rather than lepidosaurs. Archosauromorphs first appeared during the late Middle Permian or Late Permian, though they became much more common and diverse during the Triassic period.
Rhynchosaurs are a group of extinct herbivorous Triassic archosauromorph reptiles, belonging to the order Rhynchosauria. Members of the group are distinguished by their triangular skulls and elongated, beak like premaxillary bones. Rhynchosaurs first appeared in the Early Triassic, reaching their broadest abundance and a global distribution during the Carnian stage of the Late Triassic.
Lycorhinus is a genus of heterodontosaurid ornithischian dinosaur from the Early Jurassic strata of the Elliot Formation located in the Cape Province, South Africa.
Proterosuchus is an extinct genus of archosauriform reptiles that lived during the Early Triassic. It contains three valid species: the type species P. fergusi and the referred species P. alexanderi and P. goweri. All three species lived in what is now South Africa. The genus was named in 1903 by the South African paleontologist Robert Broom. The genus Chasmatosaurus is a junior synonym of Proterosuchus.
The Cynognathus Assemblage Zone is a tetrapod biozone utilized in the Karoo Basin of South Africa. It is equivalent to the Burgersdorp Formation, the youngest lithostratigraphic formation in the Beaufort Group, which is part of the fossiliferous and geologically important Karoo Supergroup. The Cynognathus Assemblage Zone is the youngest of the eight biozones found in the Beaufort Group, and is considered to be late Early Triassic (Olenekian) to early Middle Triassic (Anisian) in age. The name of the biozone refers to Cynognathus crateronotus, a large and carnivorous cynodont therapsid which occurs throughout the entire biozone.
Mesosuchus is an extinct genus of basal Rhynchosaur from early Middle Triassic deposits of Eastern Cape, South Africa. It is known from the holotype SAM 5882, a partial skeleton, and from the paratypes SAM 6046, SAM 6536, SAM 7416 and SAM 7701 from the Aliwal North Euparkeria site. Mesosuchus is quite small, spanning around 30 cm in length. Mesosuchus was discovered and named by David Meredith Seares Watson in 1912.
Eosuchus is an extinct genus of eusuchian crocodylomorph, traditionally regarded as a gavialoid crocodilian. It might have been among the most basal of all gavialoids, lying crownward of all other known members of the superfamily, including earlier putative members such as Thoracosaurus and Eothoracosaurus. Fossils have been found from France as well as eastern North America in Maryland, Virginia, and New Jersey. The strata from which specimens have been found date back to the late Paleocene and early Eocene epochs.
Isalorhynchus is an extinct genus of hyperodapedontine rhynchosaur from the late Triassic period of Toliara Province, southwestern Madagascar. It is known from the holotype MDE-R18, a nearly complete maxilla and from other specimens from the same locality, Malio River area. It was found in the Makay Formation of the Morondava Basin. It was first named by Eric Buffetaut in 1983 and the type species is Isalorhynchus genovefae. The majority of Isalorhynchus specimens are isolated jaw bones, but two nearly complete skeletons were found in 1998. Langer et al., 2000 concluded that Isalorhynchus is a synonym of Hyperodapedon and referred it to a new species of Hyperodapedon. Whatley, 2005 retained this genus as valid with a description of new materials in her PhD thesis. Montefeltro et al., 2010 and Langer et al., 2010 accepted Isalorhynchus as valid genus.
Howesia is an extinct genus of basal rhynchosaur from early Middle Triassic deposits of Eastern Cape, South Africa. It is known from the holotype SAM 5884, a partial skeleton with palate and partial lower jaws and from two paratypes, SAM 5885 and SAM 5886. It was found in the Burgersdorp Formation of the middle deposits of the Beaufort Group and referred to Subzone B of the Cynognathus Assemblage Zone. It was first named by Robert Broom in 1905 and the type species is Howesia browni, named after Alfred Brown.
Mesodapedon is an extinct genus of hyperodapedontid rhynchosaur from middle Triassic deposits of India. It is known from the holotype ISIR-300 and from the paratype ISIR-301 from the Yerrapalli Formation. It was first named by Sankar Chatterjee in 1980 and the type species is Mesodapedon kuttyi. It is extremely closely related to the Tanzanian Stenaulorhynchus and even was considered to be its synonym.
Protorosauria is an extinct, likely paraphyletic group of basal archosauromorph reptiles from the latest Middle Permian to the end of the Late Triassic of Asia, Europe and North America. It was named by the English anatomist and paleontologist Thomas Henry Huxley in 1871 as an order, originally to solely contain Protorosaurus. Other names which were once considered equivalent to Protorosauria include Prolacertiformes and Prolacertilia.
Prolacerta is a genus of archosauromorph from the lower Triassic of South Africa and Antarctica. The only known species is Prolacerta broomi. The generic name Prolacerta is derived from Latin meaning “before lizard” and its species name broomi is in commemoration of the famous paleontologist Robert Broom, who discovered and studied many of the fossils found in rocks of the Karoo Supergroup. When first discovered, Prolacerta was considered to be ancestral to modern lizards, scientifically known as lacertilians. However, a study by Gow (1975) instead found that it shared more similarities with the lineage that would lead to archosaurs such as crocodilians and dinosaurs. Prolacerta is considered by modern paleontologists to be among the closest relatives of the Archosauriformes.
Eorasaurus is an extinct genus of archosauromorph reptile known from the middle Late Permian of Tatarstan, European Russia. It contains a single species, Eorasaurus olsoni. When originally described by Sennikov (1997), Eorasaurus was identified as an early archosauromorph and assigned to the family Protorosauridae, Ezcurra et al. (2014) and Ezcurra (2016) later reclassified Eorasaurus and placed it within the group Archosauriformes. Eorasaurus is based solely on scant fossil material from the neck region, and is thus considered an unstable taxon in phylogenetic analyses. If Eorasaurus is an archosauriform, it would be the oldest known member of the group and would pre-date the previous record holder.
Aenigmastropheus is an extinct genus of early archosauromorph reptiles known from the middle Late Permian Usili Formation of Songea District, southern Tanzania. It contains a single species, Aenigmastropheus parringtoni, known solely from UMZC T836, a partial postcranial skeleton of a mature individual. It was collected in 1933, and first described in 1956, as a "problematic reptile" due to its unique morphology. Therefore, a binomial name was erected for this specimen in 2014. Aenigmastropheus was probably fully terrestrial.
Eohyosaurus is an extinct genus of basal rhynchosaur known from the early Middle Triassic Burgersdorp Formation of Free State, South Africa. It contains a single species, Eohyosaurus wolvaardti.
Pseudochampsa is an extinct genus of proterochampsid archosauriform known from the Late Triassic (Carnian) Cancha de Bochas Member of the Ischigualasto Formation of San Juan Province, Ischigualasto-Villa Unión Basin in northwestern Argentina. It contains a single species, Pseudochampsa ischigualastensis, originally named as a second species of the closely related Chanaresuchus, based on a fairly complete articulated skeleton and skull. A revision of the remains concluded that it was best to move to species to its own genus, as no traits were found to unite P. ischigualastensis and the type species of Chanaresuchus to the exclusion of other proterochampsids. A phylogenetic analysis places both species in a polytomy with Gualosuchus as the most advanced members of Proterochampsia.
Langeronyx is an extinct genus of basal rhynchosaurid known from the early Middle Triassic Bromsgrove Sandstone Formation of Warwickshire, UK. It contains a single species, Langeronyx brodiei, originally included in the genus Rhynchosaurus. R. brodiei was first described and named by Michael Benton in 1990, but its redescription by Martín D. Ezcurra, Felipe Montefeltro and Richard J. Butler in 2016 recovered it as more closely related to the more advance hyperodapedontine than to the type species of Rhynchosaurus and thus it was moved to its own genus. The generic name Langeronyx honors the Brazilian paleontologist Max Cardoso Langer in recognition of his rhynchosaur research, combined with the Greek onyx (óνυξ) meaning "claw", a common suffix for rhynchosaur genera. L. brodiei is known solely from the holotype, a partial skull divided into the two specimens WARMS G6097/1 and NHMUK PV R8495, housed in the Warwickshire Museum, Warwick and Natural History Museum, London, respectively. Other specimens originally referred to R. brodiei either do not overlap with its type or can be just as likely referred to other basal rhynchosaurids. L. brodiei is one of two basal archosauromorphs known from the Bromsgrove Sandstone Formation, the other being the lesser known Rhombopholis scutulata.
Kadimakara is an extinct genus of early archosauromorph reptile from the Arcadia Formation of Queensland, Australia. It was seemingly a very close relative of Prolacerta, a carnivorous reptile which possessed a moderately long neck. The generic name Kadimakara references prehistoric creatures from Aboriginal myths which may have been inspired by ice-age megafauna. The specific name K. australiensis relates to the fact that it was found in Australia. Prolacerta and Kadimakara were closely related to the Archosauriformes, a successful group which includes archosaurs such as crocodilians, pterosaurs, and dinosaurs.
Boreopricea is an extinct genus of archosauromorph reptile from the Early Triassic of arctic Russia. It is known from a fairly complete skeleton discovered in a borehole on Kolguyev Island, though damage to the specimen and loss of certain bones has complicated study of the genus. Boreopricea shared many similarities with various other archosauromorphs, making its classification controversial. Various studies have considered it a close relative of Prolacerta, tanystropheids, both, or neither. Boreopricea is unique among early archosauromorphs due to possessing contact between the jugal and squamosal bones at the rear half of the skull.
Palaeagama is an extinct genus of neodiapsid reptile from the Late Permian or Early Triassic of South Africa. It is based on an articulated skeleton which was probably found in the Early Triassic Lystrosaurus Assemblage Zone, or potentially the Late Permian Daptocephalus Assemblage Zone. Despite the completeness of the specimen, Palaeagama is considered as a "wildcard" taxon of uncertain affinities due to poor preservation. It was originally considered an "eosuchian", and later reinterpreted as a lizard ancestor closely related to Paliguana and Saurosternon. Modern studies generally consider it an indeterminate neodiapsid, though a few phylogenetic analyses tentatively support a position at the base of Lepidosauromorpha.
