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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 eponymous ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Youngina Skull Lateral
''Youngina'' is an extinct genus of Diapsida, diapsid Reptilia, reptile from the Late Permian Beaufort Group (''Tropidostoma Assemblage Zone, Tropidostoma''-''Dicynodon Assemblage Zone, Dicynodon'' zones) of the Karoo Red Beds of South Africa. This, and a few related forms, make up the family (biology), 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 in paleontol ... [...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 near ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eosuchia
Eosuchians are an extinct order of diapsid reptiles. Depending on which taxa are included the order may have ranged from the late Carboniferous to the Eocene but the consensus is that eosuchians are confined to the Permian and Triassic. Eosuchia was initially defined to include all "thecodontian" reptiles which did not have an antorbital fenestra but did retain tabulars, postparietals and a large pineal foramen (Broom, 1914). Broom coined the term as a new suborder for ''Youngina''. A definition for inclusion in the order is difficult: it is almost easier to list the primitively-diapsid reptiles that have not been included at one time or another. The order has almost been treated as a dustbin for diapsids that are not obviously lepidosaurian or archosaurian. One consequence has been Romer's suggestion of the alternative order Younginiformes to be applied strictly to those forms with the primitive diapsid form, in particular, a complete lowermost arch as the quadratojugal and j ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kenyasaurus
''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''. Discovery ''Kenyasaurus'' is known only from the holotype specimen, KNM-MA1, a well preserved and partially complete postcranial skeleton, lacking much of the neck, pectoral girdle and forelimb, which is hosted at the Kenya National Museum. It was found at the Mariakani locality which is located 25 miles from Mombasa, southeastern Kenya. It was collected from the upper part of the Maji ya Chumvi Beds ( Maji-Ya-Chumvi Formation). These beds form the lower part of the Middle Duruma Sandstone Series (Duruma Group) and on the basis of lithological similarities with beds in Tanzania and Madagascar were dated to the Induan and Olenekian stages of the Early Triassic period, about 251.0-245 million years ago. This specimen represents the only reptilian fossils currently known from these be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dicynodon Assemblage Zone
The ''Daptocephalus'' Assemblage Zone is a tetrapod assemblage zone or biozone found in the Adelaide Subgroup of the Beaufort Group, a majorly fossiliferous and geologically important geological Group of the Karoo Supergroup in South Africa.Rubidge, B. S. (1995). Biostratigraphy of the Beaufort Group (Karoo Supergroup). ''Biostratigraphic series''. This biozone has outcrops located in the upper Teekloof Formation west of 24°E, the majority of the Balfour Formation east of 24°E, and the Normandien Formation in the north. It has numerous localities which are spread out from Colesberg in the Northern Cape, Graaff-Reniet to Mthatha in the Eastern Cape, and from Bloemfontein to Harrismith in the Free State. The ''Daptocephalus'' Assemblage Zone is one of eight biozones found in the Beaufort Group and is considered Late Permian (Lopingian) in age. Its contact with the overlying ''Lystrosaurus'' Assemblage Zone marks the Permian-Triassic boundary. Previously known as the ''Dicynod ... [...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] |
Younginiformes
Younginiformes is a replacement name for the taxon Eosuchia, proposed by Alfred Romer in 1947. The 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 this be replaced by Younginiformes, to include the Younginidae and a very few similar families, ranging from the Permian to the Triassic. Younginiformes (including ''Acerosodontosaurus'', ''Hovasaurus'', ''Kenyasaurus'', ''Tangasaurus'', ''Thadeosaurus'', ''Youngina'', et alia sensu Currie and other researchers in the 1980s) is probably not a clade. It appears to represent a grade of South African Permo-Triassic diapsids that are not more closely related to each other as a whole than they are to other reptiles. A cladistic analysis by Laurin and Pineiro (2017) recovers Parareptilia Parareptilia ("at the side of reptiles") is a subclass or clade of basal sauropsids (reptiles), typically considered the sis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thadeosaurus
''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, 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 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 In biology, phylogenetics (; from Greek φυλή/ φῦλον [] "tribe, clan, race", and wikt:γενετικός, γενετικός [] "origin, source, birth") is the study of t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Triassic
The Triassic ( ) is a geologic period and system which spans 50.6 million years from the end of the Permian Period 251.902 million years ago ( Mya), to the beginning of the Jurassic Period 201.36 Mya. The Triassic is the first and shortest period of the Mesozoic Era. Both the start and end of the period are marked by major extinction events. The Triassic Period is subdivided into three epochs: Early Triassic, Middle Triassic and Late Triassic. The Triassic began in the wake of the Permian–Triassic extinction event, which left the Earth's biosphere impoverished; it was well into the middle of the Triassic before life recovered its former diversity. Three categories of organisms can be distinguished in the Triassic record: survivors from the extinction event, new groups that flourished briefly, and other new groups that went on to dominate the Mesozoic Era. Reptiles, especially archosaurs, were the chief terrestrial vertebrates during this time. A specialized subgroup of archo ... [...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 ance ... [...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 Sakamamena F ... [...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 com ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
