Diapsids

Diapsids ("two arches") are a clade of sauropsids, distinguished from more primitive eureptiles by the presence of two holes, known as temporal fenestrae, in each side of their skulls. The earliest traditionally identified diapsids, the araeoscelidians, appeared about three hundred million years ago during the late Carboniferous period. All diapsids other than the most primitive ones in the clade Araeoscelidia are often placed into the clade Neodiapsida. The diapsids are extremely diverse, and include birds and all modern reptile groups, including turtles, which were historically thought to li

Longisquama is a genus of extinct reptile containing only one species, L. insignis, known from a poorly preserved skeleton and several incomplete fossil impressions from the Middle to Late Triassic Madygen Formation of Kyrgyzstan. The generic name means "long scales", and the specific name insignis means "unusual", in Latin. The holotype is notable for a number of long feather-like structures growing from its back. The affinities of Longisquama among reptiles have long been contentious, with some researchers controversially connecting Longisquama and its back structures to the origin of birds

REDIRECT Diapsid Category:Diapsids Category:Reptile taxonomy Category:Guadalupian first appearances Category:Extant Permian first appearances Category:Taxa named by Michael Benton

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.

Younginiformes is a potential group of diapsid reptiles known from the Permian–Triassic of Africa. It has been used as a replacement for the more problematically-defined "Eosuchia". Younginiforms were historically suggested to be lepidosauromorphs, but are now regarded as basal non-saurian neodiapsids. Some younginiforms like Hovasaurus and Acerosodontosaurus are thought to have had an amphibious lifestyle, while others like Kenyasaurus, Thadeosaurus, and younginids were probably terrestrial.

Claudiosaurus (after the discoverer Claude Germain and saurus, 'lizard') 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.

Youngina (named after John Young (1823–1900)) is an extinct genus of small, lizard-like stem-group reptile from the Late Permian Beaufort Group (Cistecephalus–Daptocephalus assemblage zones) of the Karoo Supergroup of South Africa. Youngina has been the subject of considerable scientific attention due to its basal position within Neodiapsida (having diverged before the last common ancestor of all living reptiles) and its well-preserved skulls, with Youngina seen as providing insight into the plesiomorphic (ancestral) morphology of the last common ancestor of living reptiles.

Helveticosaurus is an extinct genus of diapsid marine reptile known from the Middle Triassic (Anisian-Ladinian boundary) of southern Switzerland and Italy. It contains a single species, Helveticosaurus zollingeri, mainly known from a nearly complete holotype skeleton, PIMUZ T 4352. The skeleton was collected at the Cava Tre Fontane site on Monte San Giorgio, a mountain well known for its rich record of marine life during the Middle Triassic.

Thadeosaurus is an extinct genus of diapsid reptiles from the late Permian Lower Sakamena Formation (Sakamena Group) of Madagascar. The genus contains a single species, Thadeosaurus colcanapi, known from several specimens preserved as natural molds.

Eunotosaurus (Latin: stout-backed lizard) is an extinct genus of reptile of disputed affinities. It is known from the late Middle Permian (Capitanian stage) of the Karoo Supergroup of South Africa and the Mwesia Beds of Malawi. Its ribs are wide and flat, forming broad plates similar to a primitive turtle shell, and the vertebrae are comparable to those of some turtles. Accordingly, Eunotosaurus has often been considered as a possible transitional fossil between turtles and their prehistoric ancestors. However, it is possible that these turtle-like features evolved independently of the same fe

Acerosodontosaurus is an extinct genus of neodiapsid reptiles that lived during the Late 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.

Orovenator is an extinct genus of early reptile from Lower Permian (Artinskian stage) deposits of Oklahoma, United States. Orovenator was originally interpreted as a basal neodiapsid, but recent phylogenetic analyses have instead placed Orovenator among earlier-diverging stem reptiles.

Avicephala ("bird heads") is a potentially polyphyletic grouping of extinct diapsid reptiles that lived during the Late Permian and Triassic periods characterised by superficially bird-like skulls and arboreal lifestyles. As a clade, Avicephala is defined as including the gliding weigeltisaurids and the arboreal drepanosaurs to the exclusion of other major diapsid groups. This relationship is not recovered in the majority of phylogenetic analyses of early diapsids and so Avicephala is typically regarded as an artificial or unnatural grouping. However, the clade was recovered again in 2021 foll

Pachystropheus (After Greek Pachys, "Thick" and Strophaios, Vertebrae) is a genus of prehistoric thalattosaurian marine reptile, from the Rhaetian (Late Triassic) of southwestern England. It is the youngest known thalattosaur.

Tangasaurus is an extinct genus of aquatic basal tangasaurid neodiapsid known from the Late Permian period (late Changhsingian stage) of Tanga, northeastern Tanzania. It contains a single species, Tangasaurus mennelli.

Tangasauridae is an extinct family of diapsids known from fossils found in Late Permian to Early Triassic rocks in Madagascar, Kenya and Tanzania. Fossils have been found of members of this family in different stages of ontogenic development. Material from the early Triassic Middle Sakamena Formation of the Morondava Basin of Madagascar indicates that the Tangasauridae survived the Permian-Triassic extinction event.

Kenyasaurus is an extinct genus of basal tangasaurid known from the Early Triassic period of Coast Province, southeastern Kenya. It contains a single species, Kenyasaurus mariakaniensis.