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Procolophonomorphs
Procolophonomorpha is an Order (biology), order 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 Clade, 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. Classification The foll ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gzhelian
The Gzhelian ( ) is an age in the ICS geologic time scale or a stage in the stratigraphic column. It is the youngest stage of the Pennsylvanian, the youngest subsystem of the Carboniferous. The Gzhelian lasted from to Ma. It follows the Kasimovian age/stage and is followed by the Asselian age/stage, the oldest subdivision of the Permian system. The Gzhelian is more or less coeval with the Stephanian Stage of the regional stratigraphy of Europe. Name and definition The Gzhelian is named after the Russian village of Gzhel (), nearby Ramenskoye, not far from Moscow. The name and type locality were defined by Sergei Nikitin (1851–1909) in 1890. The base of the Gzhelian is at the first appearance of the Fusulinida genera '' Daixina'', '' Jigulites'' and '' Rugosofusulina'', or at the first appearance of the conodont ''Streptognathodus zethus''. The top of the stage (the base of the Permian system) is at the first appearance of the conodont ''Streptognathodus isolat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clade
In biology, a clade (), also known as a Monophyly, monophyletic group or natural group, is a group of organisms that is composed of a common ancestor and all of its descendants. Clades are the fundamental unit of cladistics, a modern approach to taxonomy adopted by most biological fields. The common ancestor may be an individual, a population, or a species (extinct or Extant taxon, extant). Clades are nested, one in another, as each branch in turn splits into smaller branches. These splits reflect evolutionary history as populations diverged and evolved independently. Clades are termed ''monophyletic'' (Greek: "one clan") groups. Over the last few decades, the cladistic approach has revolutionized biological classification and revealed surprising evolutionary relationships among organisms. Increasingly, taxonomists try to avoid naming Taxon, taxa that are not clades; that is, taxa that are not Monophyly, monophyletic. Some of the relationships between organisms that the molecul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Colobomycter Pholeter
''Colobomycter'' is an extinct genus of acleistorhinid parareptile known from the Early Permian of Oklahoma. Discovery The type species, ''Colobomycter pholeter'', was first described from fossil remains in 1958, at which time it was believed to represent a synapsid, specifically, a pelycosaur. However, the discovery of new material and reexamination of the holotype led to its reclassification as a member of the Eureptilia. More recent studies indicate that ''Colobomycter'' is properly placed within the amniote clade Parareptilia, as part of the group Lanthanosuchoidea and closely related to the taxon '' Acleistorhinus''. A second species of ''Colobomycter'' was described in 2016, ''Colobomycter vaughni''. No postcranial material is known for ''Colobomycter'', and the skull material referred to the genus has all been recovered from a single locality, the Richards Spur site at the Dolese Brothers Limestone Quarry, 11 kilometers north of Fort Sill, Comanche County, Oklahoma, da ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Feeserpeton Oklahomensis
''Feeserpeton'' is an extinct genus of parareptile from the Early Permian of Richard's Spur, Oklahoma. It is known from a single species, ''Feeserpeton oklahomensis'', which was named in 2012 on the basis of a nearly complete skull. ''Feeserpeton'' is a member of the clade Lanthanosuchoidea and is one of the earliest parareptiles. Description The only known skull of ''Feeserpeton'' is small, but well-fused bones, deep pitting, and worn teeth indicate that the individual was close to maturity when it died. Large eye sockets may indicate that ''Feeserpeton'' was nocturnal. The skull is nearly complete, missing parts of the premaxilla (a bone at the tip of the snout) and the jugal (a bone making up the "cheek" region). A combination of features distinguish ''Feeserpeton'' from other related parareptiles, including a triangular skull, large caniniform teeth in the upper and lower jaws, and postorbital bones behind the eye sockets that are much larger than the nearby squamosal bones. P ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Australothyris Smithi
''Australothyris'' is an extinct genus of basal procolophonomorph parareptile known from the Middle Permian (middle Capitanian stage) of ''Tapinocephalus'' Assemblage Zone, South Africa. The type and only known species is ''Australothyris smithi''. As the most basal member of Procolophonomorpha, ''Australothyris'' helped to contextualize the origin of this major parareptile subgroup. It has been used to support the hypotheses that procolophonomorphs originated in Gondwana and ancestrally possess temporal fenestrae, due to its large and fully enclosed temporal fenestra and South African heritage. It also possessed several unique features, including a high tooth number, long postfrontal, small interpterygoid vacuity, and a specialized interaction between the stapes and quadrate. Discovery Australothyris is known from a single specimen discovered at the Beukesplaas farm by Robert Smith in 1995. The fossil site at the Beukesplaas farm contains a diverse parareptile and synapsid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Millerosauria
Millerosauria is an order of Parareptiles that contains the families †Millerettidae and † Eunotosauridae. It is the sister group to the order Procolophonomorpha. It was named in 1957 by Watson. It was once considered a suborder of the disused group Captorhinida and was called Millerosauroidea. All members of this order are thought to be extinct. ''Eunotosaurus ''Eunotosaurus'' (''Latin (language), Latin'': Stout-backed lizard) is an extinct genus of amniote, possibly a close relative of turtles. ''Eunotosaurus'' lived in the late Middle Permian (Capitanian stage) and fossils can be found in the Karoo ...'' has been recovered as a stem-turtle in recent cladistic studies.Schoch RR, Sues HD (2015) A Middle Triassic stem-turtle and the evolution of the turtle body plan. Nature doi: 10.1038/nature14472. pub ahead of print/ref> References * Parareptilia Prehistoric tetrapod orders Guadalupian first appearances Lopingian extinctions {{permian-reptile-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mesosaurus
''Mesosaurus'' (meaning "middle lizard") is an extinct genus of reptile from the Early Permian of southern Africa and South America. Along with it, the genera '' Brazilosaurus'' and '' Stereosternum'', it is a member of the family Mesosauridae and the order Mesosauria. ''Mesosaurus'' was long thought to have been one of the first marine reptiles, although new data suggests that at least those of Uruguay inhabited a hypersaline water body, rather than a typical marine environment. In any case, it had many adaptations to a fully aquatic lifestyle. It is usually considered to have been anapsid, although Friedrich von Huene considered it to be a synapsid. Recent study of Mesosauridae phylogeny places the group as either the basal most clade within Parareptilia or the basal most clade within Sauropsida (with the latter being the less supported position) despite the skull of ''Mesosaurus'' possessing the "Synapsid condition" of one temporal fenestra. Discovery and naming The ho ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parareptilia
Parareptilia ("near-reptiles") is an extinct group of basal sauropsids (" reptiles"), traditionally considered the sister taxon to Eureptilia (the group that likely contains all living reptiles and birds). Parareptiles first arose near the end of the Carboniferous period and achieved their highest diversity during the Permian period. Several ecological innovations were first accomplished by parareptiles among reptiles. These include the first reptiles to return to marine ecosystems (mesosaurs), the first bipedal reptiles ( bolosaurids such as '' Eudibamus''), the first reptiles with advanced hearing systems ( nycteroleterids and others), and the first large herbivorous reptiles (the pareiasaurs). The only parareptiles to survive into the Triassic period were the procolophonoids, a group of small generalists, omnivores, and herbivores. The largest family of procolophonoids, the procolophonids, rediversified in the Triassic, but subsequently declined and became extinct by t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cladogram
A cladogram (from Greek language, Greek ''clados'' "branch" and ''gramma'' "character") is a diagram used in cladistics to show relations among organisms. A cladogram is not, however, an Phylogenetic tree, evolutionary tree because it does not show how ancestors are related to descendants, nor does it show how much they have changed, so many differing evolutionary trees can be consistent with the same cladogram. A cladogram uses lines that branch off in different directions ending at a clade, a group of organisms with a last common ancestor. There are many shapes of cladograms but they all have lines that branch off from other lines. The lines can be traced back to where they branch off. These branching off points represent a hypothetical ancestor (not an actual entity) which can be inferred to exhibit the traits shared among the terminal taxa above it. This hypothetical ancestor might then provide clues about the order of evolution of various features, adaptation, and other e ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diapsid
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 lie outside the group. All modern reptiles and birds are placed within the neodiapsid subclade Sauria. Although some diapsids have lost either one hole (lizards), or both holes (snakes and turtles), or have a heavily restructured skull (modern birds), they are still classified as diapsids based on their ancestry. At least 17,084 species of diapsid animals are extant: 9,159 birds, and 7,925 s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pappochelys
''Pappochelys'' ( meaning "grandfather turtle" in Greek) is an extinct genus of diapsid reptile possibly related to turtles. The genus contains only one species, ''Pappochelys rosinae'', from the Middle Triassic of Germany, which was named by paleontologists and Hans-Dieter Sues in 2015. The discovery of ''Pappochelys'' provides strong support for the placement of turtles within Diapsida, a hypothesis that has long been suggested by molecular data, but never previously by the fossil record. It is morphologically intermediate between the definite stem-turtle '' Odontochelys'' from the Late Triassic of China and ''Eunotosaurus'', a reptile from the Middle Permian of South Africa. Description ''Pappochelys'' had a wide body, small skull, and a long tail that makes up about half of the total body length, which is up to . The skull is pointed with large eye sockets. Several turtle-like features are present, including expanded ribs and gastralia that seem to be precursors of a shel ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
