Dimorphodon was a genus of medium-sized pterosaur from Europe during the early Jurassic Period. It was named by paleontologist Richard Owen in 1859. Dimorphodon means "two-form tooth", derived from the Greek δι meaning "two", μορφη meaning "shape" and οδων meaning "tooth", referring to the fact that it had two distinct types of teeth in its jaws – which is comparatively rare among reptiles. The diet of Dimorphodon has been questioned among researchers, with earlier interpretations depicting it as an insectivore or a piscivore. Recent studies have suggested that Dimorphodon likely hunted small vertebrates, though it still would have consumed soft invertebrates like insects.
Oligokyphus is an extinct genus of herbivorous tritylodontid cynodont known from the Late Triassic to Early Jurassic of Europe, Asia and North America.
The Fremouw Formation is a Triassic-age rock formation in the Transantarctic Mountains of Antarctica. It contains the oldest known fossils of tetrapods from Antarctica, including synapsids, reptiles and amphibians. Fossilized trees have also been found. The formation's beds were deposited along the banks of rivers and on floodplains. During the Triassic, the area would have been a riparian forest at 70–75°S latitude.
Cynosphenodon is an extinct genus of rhynchocephalian in the family Sphenodontidae from the Middle Jurassic La Boca Formation of Tamaulipas, Mexico. It is known from a largely complete lower jaw and fragments of the upper jaw. It is suggested to be among the closest known relatives of the tuatara, with both being placed in the Sphenodontinae, which is supported by among other characters, the growth pattern of the teeth.
The La Boca Formation is a geological formation in Tamaulipas state, northeast Mexico. It was thought to date back to the Early Jurassic, concretely the Pliensbachian stage epoch. Although, the latest studies had proven that the local Vulcanism, related to the aperture of the Atlantic Ocean and the several Rift Events, that continue until the Bajocian, while the unit itself was likely deposited between the earliest Pliensbachian, as proven by zircon with the fossil taxa deposited on the rocks above, likely of Late Pliensbachian-Lower Toarcian age, and the upper section of Late Toarcian-Late Aalenian age. Due to successions of Aalenian depositional sistems on the upper layers of the Huizachal Canyon, has been delimited the formation to the Toarcian stage, being the regional equivalent of the Moroccan Azilal Formation. Deposits of Late Triassic Age referred to this unit have been reclassified in a new formation, El Alamar Formation. In North America, La Boca Formation was found to be a regional equivalent of the Eagle Mills redbeds of southern United States, the Todos Santos Formation of southern Mexico and the Barracas Group of the Sonora desert region.
Ptychoceratodus is an extinct genus of lungfish living from Early Triassic to Middle Jurassic. It was established by Otto Jaekel for one species, transferred from Ceratodus genus. Type species is P. serratus from the Middle Triassic of Switzerland and Germany. Ptychoceratodus had two pairs of massive dental plates, bearing 4-6 acute ridges. Its skull roof was composed from massive, plate-like bones. In the central part of skull roof was localized an unossified fenestra. Most of the Ptychoceratodus findings are isolated dental plates, some associated with jaws. Other parts of skull or postcranial skeleton are relatively rarely found as fossils. The anatomy of skull is the best recognized in P. serratus, whereas less complete cranial material is available also for P. concinuus, P. phillipsi, and P. rectangulus. Although Ptychoceratodus is known exclusively from the Triassic and Jurassic, there were also Cretaceous specimens referred to this genus. However, they are more often regarded as representants of Metaceratodus. Ptychoceratodus is the only member of the family Ptychoceratodontidae. The first named species is P. phillipsi by Louis Agassiz in 1837 as a species of Ceratodus and later moved to Ptychoceratodus genus. Occurrences of Ptychoceratodus come mainly from Europe. However, occurrences from other continents suggest it was dispersed globally during the Triassic. After 2010, the new fossil material behind the Europe was reported from South America, India, and Greenland
Theretairus is a Late Jurassic genus of sphenodont reptile from the Morrison Formation of western North America, present in stratigraphic zones 5 and 6.
Monofenestrata is an unranked group of pterosaurs that includes the family Wukongopteridae and the suborder Pterodactyloidea.
Godavarisaurus is an extinct genus of sphenodontian reptile from the Early-Middle Jurassic Kota Formation of Andhra Pradesh, India. It is known from jaw fragments. It was a small sphenodontian, with the skull estimated to be less than 2 centimetres (0.79 in) long. It is generally considered to be a relatively basal sphenodontian that lies outside Eusphenodontia.
Zapatadon is an extinct genus of sphenodontid reptile from the end of the Early Jurassic in the lower part of La Boca Formation of Tamaulipas, Mexico. Is known from a nearly complete skull with mandible of a post-hatchling individual, and is one of the smallest skulls between the sphenodontians, with an estimated total length of 11.3 millimetres, a bit smaller than the hatchling individuals observed in the modern tuatara (Sphenodon); features like the oblique mandibular symphysis suggests that the holotype is from an individual in a relatively mature stage of ontogenic development. Zapatadon is diagnosed by their hatchling tooth series located in a depression in the anterior part of the dentary bone, the prefrontal bone surrounding the dorsal process of the maxilla and the broad jugal that extends over the maxillary suborbital process, been almost excluded of the orbit.
Pamizinisaurus is a genus of sphenodontian reptile known from Lower Cretaceous (Albian) Tlayúa Formation of central Mexico. It was named Pamizinsaurus tlayuaensis by Reynoso in 1997, after Tlayua Quarry were it was found. It is known from the crushed skeleton of a juvenile individual, with a skull length of around 16 millimetres (0.63 in), and a total length of about 77 millimetres (3.0 in). The fossil was covered in small round osteoscutes, unique among known sphenodontians but similar to those of helodermatid lizards like the Gila monster, which probably served to protect it from predators.
Christian Alfred Sidor is an American vertebrate paleontologist. He is currently a Professor in the Department of Biology, University of Washington in Seattle, as well as Curator of Vertebrate Paleontology and Associate Director for Research and Collections at the Burke Museum of Natural History and Culture. His research focuses on Permian and Triassic tetrapod evolution, especially on therapsids.
The Colorado City Formation is a Late Triassic geologic formation in the Dockum Group of Texas, United States. It has previously been known as the Iatan Member, Colorado City Member or 'Pre-Tecovas Horizon'.
Paramacellodidae is an extinct family of lizards that first appeared in the Middle Jurassic around 170 million years ago (Ma) and became extinct at the end of the Cretaceous around 66 Ma. It was one of the earliest groups of lizards to have undergone an evolutionary radiation, with members found across the supercontinent Laurasia. The phylogenetic relationships and constituent species of Paramacellodidae are uncertain. Many studies regard them to be scincomorphs, a large group that includes skinks and their closest extinct relatives, and possibly also to Cordyoidea, a group that includes spinytail lizards and relatives. Like modern skinks, paramacelloidids had rectangular bony plates called osteoderms covering most of their bodies, including their backs, undersides, and tails. They also had short and robust limbs. Paramacellodids are distinguished from other lizards by the combination two traits in their dentition, the teeth are labiolingually expanded at their bases, and the tooth apices are lingually concave.
Sphenovipera jimmysjoyi is an extinct species of sphenodontian dated from the Middle Jurassic. If was discovered in the lower part of the La Boca Formation located in Tamaulipas, Mexico. Only the lower jaw of this organism has been discovered and studied. It is possibly the only species of rhynchocephalian yet discovered to show evidence of venom delivery.
Rebbanasaurus is an extinct sphenodontian reptile known from remains found in the Early-Middle Jurassic Kota Formation of India. The type specimen is a partial jawbone which has acrodont teeth, with other known remains including fragments of the premaxilla, maxilla, and palatine. It was relatively small, with a skull estimated at 1.5–2.5 centimetres (0.59–0.98 in) long. It is generally considered to be a relatively basal sphenodontian that lies outside Eusphenodontia.
Bocaconodon is an early mammaliaform genus that lived during the Pliensbachian of Mexico. The type and only species, Bocaconodon tamaulipensis, was named and described in 2008. It is known from a single specimen, a partial right dentary bone preserving two nearly complete molar teeth and the rear portion of a third molar. The specimen was found at the Huizachal Canyon locality, "a Pliensbachian floodplain siltstone in the La Boca Formation".
The epipterygoid is a paired cranial bone present in many tetrapods. It acts as a vertical strut connecting the pterygoid bone of the palate to the outer surface of the braincase or the underside of the skull roof. The epipterygoid is an endochondral bone, similar to the braincase but unlike most other bones in the skull. In squamates, the epipterygoid generally has a slender rod-like shape, and is also known as the columella cranii. The epipterygoid is considered to be homologous to the alisphenoid bone of mammals. Though present in many extinct archosaurs, it has been independently lost in modern crocodilians and birds.
The postfrontal is a paired cranial bone found in many tetrapods. It occupies an area of the skull roof between and behind the orbits, lateral to the frontal and parietal bones, and anterior to the postorbital bone.
