Related Research Articles
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.
Baru, sometimes referred to as the cleaver-headed crocodile, is an extinct genus of Australian mekosuchine crocodilian. Its fossils have been found from various Late Oligocene and Miocene localities from across the Northern Territory and Queensland, indicating that Baru was a common genus during the late Paleogene and early Neogene. Three species are recognized, B. darrowi, B. iylwenpeny, and B. wickeni.
Purussaurus is an extinct genus of giant caiman that lived in South America during the Miocene epoch, from the Friasian to the Huayquerian in the SALMA classification. It is known from skull material found in the Brazilian and Peruvian Amazon, Argentina, Colombian Villavieja Formation, Panamanian Culebra Formation, Urumaco and Socorro Formations of northern Venezuela.
Peltosaurus is an extinct genus of anguid lizard from North America that lived from the Eocene to the Oligocene. Peltosaurus belongs to the anguid subfamily Glyptosaurinae. The type species Peltosaurus granulosus was named in 1873 by American paleontologist Edward Drinker Cope. Many additional species have been named, but most have been reassigned to different genera. For example, Peltosaurus piger, named in 1928, was reclassified as Odaxosaurus piger, and P. jepseni, named in 1942 from the Paleocene of Wyoming, but was later reclassified as Proxestops jepseni. In 1955 a new species, Peltosaurus macrodon, was named from the Eocene of California. Lizard bones from the Late Miocene of Nebraska were attributed to a new species of Peltosaurus called P. minimus in 1976, extending the fossil range of Peltosaurus and Glyptosaurinae into the Neogene. However, these bones were later referred to a genus of skinks called Eumeces, meaning that the fossil range of Peltosaurus and Glyptosaurinae does not go beyond the Paleogene.
Stupendemys is an extinct genus of freshwater side-necked turtle, belonging to the family Podocnemididae. It is the largest freshwater turtle known to have existed, with a carapace over 2 meters long. Its fossils have been found in northern South America, in rocks dating from the Middle Miocene to the very start of the Pliocene, about 13 to 5 million years ago. Male specimens are known to have possessed bony horns growing from the front edges of the shell and the discovery of the fossil of a young adult shows that the carapace of these turtles flattens with age. A fossil skull described in 2021 indicates that Stupendemys was a generalist feeder.
Orthosuchus is an extinct genus of crocodyliform that lived during the Early Jurassic, about 196 million years ago. It was first discovered in 1963 in the Red Beds Formation in the Qacha's Nek Province of Lesotho, southern Africa. The characteristics showed on its postcranial skeleton and the skull indicated that it is a crocodyliform. The finding is significant since some of the characteristics found on this specimen were believed to be absent until Jurassic.
Australosuchus is an extinct monospecific genus of crocodylian belonging to the subfamily Mekosuchinae. The type and only known species Australosuchus clarkae lived during the Late Oligocene and the Early Miocene in the Lake Eyre Basin of South Australia. It was described in 1991 by Paul Willis and Ralph Molnar from fossil material discovered at Lake Palankarinna.
Mourasuchus is an extinct genus of giant, aberrant caiman from the Miocene of South America. Its skull has been described as duck-like, being broad, flat, and very elongate, superficially resembling Stomatosuchus from the Late Cretaceous.
Calsoyasuchus is a genus of crocodylomorph that lived in the Early Jurassic. Its fossilized remains were found in the Sinemurian-Pliensbachian-age Kayenta Formation on Navajo Nation land in Coconino County, Arizona, United States. Formally described as C. valliceps, it is known from a single incomplete skull which is unusually derived for such an early crocodile relative. This genus was described in 2002 by Ronald Tykoski and colleagues; the specific name means "valley head" and refers to a deep groove along the midline of the nasal bones and frontal bones. It has often been interpreted as the earliest diverging member of Goniopholididae, but other studies have recovered it in various other positions.
Asiatosuchus is an extinct genus of crocodyloid crocodilians that lived in Eurasia during the Paleogene. Many Paleogene crocodilians from Europe and Asia have been attributed to Asiatosuchus since the genus was named in 1940. These species have a generalized crocodilian morphology typified by flat, triangular skulls. The feature that traditionally united these species under the genus Asiatosuchus is a broad connection or symphysis between the two halves of the lower jaw. Recent studies of the evolutionary relationships of early crocodilians along with closer examinations of the morphology of fossil specimens suggest that only the first named species of Asiatosuchus, A. grangeri from the Eocene of Mongolia, belongs in the genus. Most species are now regarded as nomina dubia or "dubious names", meaning that their type specimens lack the unique anatomical features necessary to justify their classification as distinct species. Other species such as "A." germanicus and "A." depressifrons are still considered valid species, but they do not form an evolutionary grouping with A. grangeri that would warrant them being placed together in the genus Asiatosuchus.
Euthecodon is an extinct genus of long-snouted crocodile. It was common throughout much of Africa during the Neogene, with fossils being especially common in Kenya, Ethiopia, and Libya. Although superficially resembling that of gharials, the long snout was a trait developed independently from that of other crocodilians and suggests a diet of primarily fish. Euthecodon coexisted with a wide range of other crocodiles in the areas it inhabited before eventually going extinct during the Pleistocene.
Saniwa is an extinct genus of varanid lizard that lived during the Eocene epoch. It is known from well-preserved fossils found in the Bridger and Green River Formations of Wyoming, United States. The type species S. ensidens was described in 1870 as the first fossil lizard known from North America. A second species, S.orsmaelensis, is recognised from remains found in Europe. It is a close relative of Varanus, the genus that includes monitor lizards.
Culebrasuchus is an extinct, monotypic genus of caiman alligatorid known from the Early to Middle Miocene (Hemingfordian) of the Panama Canal Zone of Panama. It contains a single species, Culebrasuchus mesoamericanus.
Barbaturex is an extinct genus of giant herbivorous iguanian lizards from Pondaung Formation, the Eocene of Myanmar. It is represented by a single species, Barbaturex morrisoni, which is known from several partial dentaries and a fused pair of frontals, two bones that form part of the top of the skull. Based on the size of these bones, Barbaturex morrisoni is estimated to have been about 1 metre (3.3 ft) from snout to vent, and possibly up to 6 feet (1.8 m) including the tail. Barbaturex morrisoni was named after The Doors frontman Jim Morrison, a play on his epithet "The Lizard King". The genus's name is a portmanteau of the Latin words Barbatus and rex, meaning "bearded king", in reference to ridges along the mandible and the lizard's large size.
Myrmecodaptria is an extinct genus of scleroglossan lizard from the Late Cretaceous Djadokhta Formation in Ukhaa Tolgod, Mongolia. The type and only species, Myrmecodaptria microphagosa, was named in 2000 by paleontologists Gao Keqin and Mark Norell. Myrmecodaptria is known from a single holotype skull and lower jaws. It is distinguished from all other lizards by its extremely elongated skull. The eyes are placed close to the snout, which is short and rounded. The top of the skull is covered in bony knobs called osteoderms. The parietal bone at the back of the skull is elongated and about as long as the frontal bones, which are the usually the longest bones along the top of the skull in lizards. The squamosal bone at the back of the skull reaches forward to connect with the jugal bone behind the eye, forming a thin arch between the temporal fenestrae. Myrmecodaptria also has fewer and more widely spaced teeth in its jaws than do most other lizards.
The Valentine Formation is a geologic unit formation or member within the Ogallala unit in northcentral Nebraska near the South Dakota border. It preserves fossils dating to the Miocene epoch of the Neogene period and is particularly noted for Canid fossils. This unit consists of loosely-consolidated sandstone that crumbles easily. These sands carry the water of the Ogallala Aquifer and is the source of much of the water in the Niobrara River. A particular feature of the Valentine is lenticular beds of green-gray opaline sandstone that can be identified in other states, including South Dakota, Nebraska, Kansas, and Colorado. Although three mammalian fauna stages can be mapped throughout the range of the Ogallala, no beddings of the Ogallala are mappable and all attempts of formally applying the Valentine name to any mappable lithology beyond the type location have been abandoned. Even so, opaline sandstone has been used to refer to this green-gray opalized conglomerate sandstone that is widely found in the lower Ogallala Formation.
Carusia is an extinct genus of lizards from the Late Cretaceous of Mongolia. It is a close relative of the family Xenosauridae, which includes living knob-scaled lizards. Fossils of the type and only species Carusia intermedia come from the late-Campanian age Barun Goyot Formation and have been found in the Flaming Cliffs, Ukhaa Tolgod, and Kheerman Tsav fossil localities. Carusia was first described in 1985 under the name Carolina intermedia, but since the name Carolina was preoccupied by a genus of scarab beetles that had been named in 1880, it was renamed Carusia intermedia. Carusia had initially been known from fragmentary skull material, complicating efforts to determine its evolutionary relationships with other lizards; it had variously been described as an indeterminate scincomorph, a xenosaurid, or some other type of autarchoglossan lizard convergent with xenosaurids. However, the discovery of 35 complete skulls in the 1990s, three of which were described in a detailed 1998 monograph, revealed that Carusia was the sister taxon of Xenosauridae, compelling the authors of the monograph to create a new clade called Carusioidea to include both taxa.
Oardasaurus is an extinct genus of lizard from the latest Cretaceous of Romania. It is a member of the Barbatteiidae, a group of lizards closely related to the Teiidae. At 20 centimetres (7.9 in) in length, it was much smaller than the only other named member of the Barbatteiidae, Barbatteius, which lived slightly later. Like Barbatteius, Oardasaurus can be identified by the presence of a crust of bone deposits, or osteoderms, on the roof of its skull; it differs from Barbatteius in the pattern of the sculpturing on this crust. Both Oardasaurus and Barbatteius lived in the isolated island ecosystem of Hațeg Island, having rapidly diversified into various generalist predators of small prey after their arrival on the island during the Early Cretaceous. They went extinct in the Cretaceous–Paleogene extinction event.
Caiman brevirostris is an extinct species of caiman that lived during the Late Miocene, around 11.6 million years ago, to the end of the Miocene 5.3 million years ago in Acre and Amazonas, Brazil as well as Urumaco, Venezuela. Several specimens have been referred to the species, but only 3 of them are confidently placed in the species. C. brevirostris was originally named in 1987 on the basis of a single, incomplete rostrum with an associated mandibular ramus that had been found in Acre, Brazil. C. brevirostris is very distinct among Caiman species and caimaninae overall in that it preserves a characteristically short and robust skull that bears blunt posterior teeth that were built to break down harder foods. This was an adaption for durophagy, likely to crush shells of mollusks and clams which were common in the wetlands that C. brevirostris resided in.
Andrias matthewi, or Matthew's giant salamander, is an extinct species of giant salamander from the Miocene of North America. It belongs to the genus Andrias, which contains the living Asian giant salamanders. It is the largest salamander to have ever existed, with a maximum estimated length of 2.3 m. Its fossils have been found in Nebraska, Colorado, and Saskatchewan.
References
- ↑ Holman, J. A. (1973). "New amphibians and reptiles from the Norden Bridge fauna (Upper Miocene) of Nebraska". Michigan Academician. 6: 149–163.
- ↑ Holman, J. A. (1976). "A new Peltosaurus (Reptilia, Sauria, Anguidae) from the Upper Miocene of Nebraska". Journal of Herpetology. 10 (1): 41–44. doi:10.2307/1562926. JSTOR 1562926.
- ↑ Gauthier, J.A. (1982). "Fossil xenosaurid and anguid lizards from the early Eocene Wasatch Formation, Southeast Wyoming, and a revision of the Anguioidea". Rocky Mountain Geology. 21 (1): 7–54.
- ↑ Holman, J. A. (1976). "The herpetofauna of the Lower Valentine Formation, North-Central Nebraska". Herpetologica. 32 (3): 262–268.
