|
Thadeosaurus Scale
''Thadeosaurus'' is an extinct genus of diapsid reptile belonging to the family Younginidae. Fossils have been found in the Lower Sakamena Formation (Sakamena Group) of the Morondava Basin, Madagascar in 1981 in paleontology, 1981, and date to the late Permian to the early Triassic period. Description ''Thadeosaurus'' was a lizard-like animal, with a remarkably long tail that comprised about two thirds of the animal's total length of . It also had long toes, especially on the hind legs, which would have given it a powerful stride, since the toes would still touch the ground while the foot was being raised. Combined with a strong sternum, breast bone to increase the strength in the forelimbs, this means that ''Thadeosaurus'' was probably a good runner. Below is a cladogram from Reisz ''et al.'' (2011) showing the phylogenetic position of ''Thadeosaurus'' among other early diapsids: References Prehistoric neodiapsids Prehistoric reptile genera Lopingian reptiles o ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Changhsingian
In the geologic time scale, the Changhsingian or Changxingian is the latest age or uppermost stage of the Permian. It is also the upper or latest of two subdivisions of the Lopingian Epoch or Series. The Changhsingian lasted from to 251.902 million years ago (Ma). It was preceded by the Wuchiapingian and followed by the Induan. The greatest mass extinction in the Phanerozoic eon, the Permian–Triassic extinction event, occurred during this age. The extinction rate peaked about a million years before the end of this stage. Stratigraphic definitions The Changhsingian is named after Changxing () in northern Zhejiang, China. The stage was named for the Changhsing Limestone. The name was first used for a stage in 1970; 1973: ''Permian stages names'', in: : ''The Permian and Triassic systems and their mutual boundary'', Canadian Society of Petroleum Geologists Memoir 2, pp 522–548. and was anchored in the international timescale in 1981.; 2006: ''The Global Boundary Stratotyp ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cladogram
A cladogram (from Greek ''clados'' "branch" and ''gramma'' "character") is a diagram used in cladistics to show relations among organisms. A cladogram is not, however, an 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 evolutionary narratives about an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Claudiosaurus
''Claudiosaurus'' (''claudus'' is Latin for 'lameness' and ''saurus'' means 'lizard') is an extinct genus of diapsid reptiles from the Permian Sakamena Formation of the Morondava Basin, Madagascar. The pattern of the vertebrate, girle, and limbs indicates that ''Claudiosaurus'' and '' Thadeosaurus'' share a common ancestor. History and discovery ''Claudiosaurus'' is known from the Sakamena Formation of Madagascar. ''Claudiosaurus'' is found from the Late Permian. Although a paper mentions that they have been also found in Early Triassic deposits of Madagascar, citation does not mention that ''Claudiosaurus'' is from Triassic. Biology and description ''Claudiosaurus'' was one of the first members of the Neodiapsida, a group of reptiles containing diapsids more derived than the primitive Araeoscelidia. It had a relatively long body and neck, reaching on overall length of about . It is presumed to have been partially oceanic, living its life in a way similar to the modern ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Youngina
''Youngina'' is an extinct genus of diapsid reptile from the Late Permian Beaufort Group (''Tropidostoma''-''Dicynodon'' zones) of the Karoo Red Beds of South Africa. This, and a few related forms, make up the family Younginidae, within the Order Eosuchia (proposed by Broom in 1914). Eosuchia, having become a wastebasket taxon for many probably distantly-related primitive diapsid reptiles ranging from the Late Carboniferous to the Eocene, Romer proposed that it be replaced by Younginiformes (that included Younginidae and the Tangasauridae, ranging from the Permian to the Triassic). ''Youngina'' is known from several specimens. Many of these were attributed to as separate genera and species (such as ''Youngoides'' and ''Youngopsis''), but it was later realized that they were not distinct from ''Y. capensis''. The holotype specimen of ''Youngina'' was described briefly in 1914. The "''Youngoides romeri''" specimen was first attributed to ''Youngina'', but later given its eponymou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hovasaurus
''Hovasaurus'' is an extinct genus of diapsid reptile belonging to the order Eosuchia. 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. Description ''Hovasaurus'' resembled a slender lizard, two thirds of total length was taken up by its long tail. It had snout-vent length up to long, with long tail. It was well adapted to an aquatic life, with the tail being laterally flattened like that of a sea snake. Some stones have been found in the abdomen of fossil ''Hovasaurus'', indicating the creatures swallowed these for ballast, preventing them from floating to the surface when hunting fish. Paleoenvironment The Lower Sakamamen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Acerosodontosaurus
''Acerosodontosaurus'' is an extinct genus of neodiapsid reptiles that lived during the Upper 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 marine deposits of the Lower Sakamena Formation. In conjunction with several skeletal characteristics, this may indicate that ''Acerosodontosaurus'' individuals were at least partially aquatic. ''Acerosodontosaurus'' has generally been considered a " younginiform", part of a paraphyletic grade of Permian diapsids which linked the most basal ("primitive") diapsids ( araeoscelidians such as ''Petrolacosaurus'') to more derived ("advanced") diapsids, including the earliest ancestors of modern reptiles such as crocodilians and lizards. However, its position within the grade is controversial. Initially considered a specimen of the contemporaneous '' Tangasaurus' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tangasaurus
''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''. Discovery ''Tangasaurus'' is known only from three syntypes which represent two individuals. The small individual, which is well preserved in two specimens ( part and counterpart) and is known from a partial skull and a nearly complete postcranial skeleton, was designated as the lectotype of the genus. The part slab (showing the partial skull and postcranial) is hosted at the Bulawayo Museum, Zimbabwe, while the counterpart slab SAM 6231 (showing the other side of the postcranial) is hosted at the South African Museum, Cape Town. The third syntype, SAM 6232, represents a nearly complete postcranial skeleton from a larger individual, but it is poorly preserved. All specimens were collected by F. P. Mennell in 1922 at the Mizimbazi River nea ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tangasauridae
Tangasauridae is a family of diapsids. Specimens have been found that are of Late Permian to Early Triassic in age from the Sakamena Group of western Madagascar. They lived alongside other taxa present from the Sakamena Group, including temnospondyls, rhynchosaurs, and gomphodont eucynodonts. Fossils have been found of numerous specimens of common members of this family such as '' Hovasaurus'' and '' Thadeosaurus'' in different stages of ontogenic development.Currie, Philip J and Carroll, Robert L. (1984) Ontogenic changes in the eosuchian reptile ''Thadeosaurus''. ''Journal of Vertebrate Paleontology'' 4(1):68-84 Recent material from the Middle Sakamena Formation of the Morondava Basin of Madagascar that dates back to the early Triassic period suggests that the Tangasauridae were relatively unaffected by the Permian-Triassic extinction event. Description and phylogeny Tangasaurids are known to have been a highly derived group of diapsids. One subfamily, Kenyasaurinae, is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lanthanolania
''Lanthanolania'' (meaning "forgotten butcher") is an extinct genus of diapsid from Middle Permian (Wordian stage, or uppermost Kazanian in Eastern Europe) deposits of Arkhangel'sk Province, Russia. It is known from the holotype and only specimen PIN 162/56, a nearly complete skull from the Glyadnaya Shchelya locality, Mezen river in Mesen District. It was first named by Sean P. Modesto and Robert R. Reisz in 2003 and the type species is ''Lanthanolania ivakhnenkoi''. Phylogeny Cladogram A cladogram (from Greek ''clados'' "branch" and ''gramma'' "character") is a diagram used in cladistics to show relations among organisms. A cladogram is not, however, an evolutionary tree because it does not show how ancestors are related to ... after Reisz, Modesto & Scott, 2011: References Permian reptiles of Europe Fossil taxa described in 2003 Prehistoric neodiapsids Prehistoric reptile genera {{permian-reptile-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orovenator
''Orovenator'' is an extinct genus of diapsid from Lower Permian (Artinskian stage) deposits of Oklahoma, United States. It is known from two partial skulls from the Richards Spur locality in Oklahoma. The holotype OMNH 74606 consists of a partial skull preserving snout and mandible, and the referred specimen, OMNH 74607, a partial skull preserving the skull roof, vertebrae and palatal elements. It was first named by Robert R. Reisz, Sean P. Modesto and Diane M. Scott in 2011 and the type species is ''Orovenator mayorum''. The generic name means "mountain", ''oro'', in Greek in reference to the Richards Spur locality, which was mountainous during the Permian period and "hunter", ''venator'', in Latin. The specific name honours Bill and Julie May. ''Orovenator'' is the oldest and most basal neodiapsid to date. A 2018 redescription by David Ford and Roger Benson found that ''Orovenator'' shared many similarities with varanopids, a group of reptile-like tetrapods tra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neodiapsida
Neodiapsida is a clade, or major branch, of the reptilian family tree, typically defined as including all diapsids apart from some early primitive types known as the araeoscelidians. Modern reptiles and birds belong to the neodiapsid subclade Sauria. The oldest known neodiapsid is generally considered to be '' Orovenator'' from the Early Permian (Cisuralian) of North America. Basal-non saurian neodiaspids were ancestrally lizard-like, but basal Permian neodiapsids also include specialised swimming forms ('' Hovasaurus'') the gliding lizard-like Weigeltisauridae, as well as the Triassic chameleon-like drepanosaurs. The position of the highly derived Mesozoic marine reptile groups Thalattosauria, Ichthyosauromorpha and Sauropterygia within Neodiapsida is uncertain, and they may lie within Sauria. Classification The clade Neodiapsida was given a phylogenetic definition by Laurin in 1991. He defined it as the branch-based clade containing all animals more closely related to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Araeoscelidia
Araeoscelidia or Araeoscelida is a clade of extinct diapsid reptiles superficially resembling lizards, extending from the Late Carboniferous to the Early Permian. The group contains the genera ''Araeoscelis'', ''Petrolacosaurus'', the possibly aquatic '' Spinoaequalis'', and less well-known genera such as '' Kadaliosaurus'' and '' Zarcasaurus''. This clade is considered to be the sister group to all (currently known) later diapsids. Description Araeoscelidians were small animals (less than one meter in length) looking somewhat like lizards, though they are only distantly related to true lizards. They differ from other, earlier sauropsids by their slender limbs, their elongated tail, and of course by the presence of two temporal openings, the feature defining the diapsid condition. In ''Araeoscelis'', only the upper temporal opening remains, thus resulting in a derived euryapsid condition. Genera Araeoscelidia includes well-known genera such as ''Araeoscelis'' Williston 1910, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
