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Pistosauroidea
Pistosauroidea is a group of marine reptiles within the superorder (biology), superorder Sauropterygia that first appeared in the latter part of the Early Triassic and were the ancestors of plesiosaurs. Pistosauroids are rare in Triassic marine assemblages, and are represented by only a few fossils from central Europe, the United States, and China. Recent phylogenetic analyses consider the Triassic pistosauroids to be a paraphyletic grouping, meaning that they do not form a true clade. Plesiosauria is now placed within Pistosauroidea, while the traditional pistosauroids are successively more basal (phylogenetics), basal, or primitive, sauropterygians. Below is a cladogram of pistosauroid relationships from Cheng ''et al.'' (2006): Below is a cladogram of pistosauroid relationships from Ketchum & Benson, 2011: References Sauropterygia Early Triassic first appearances Maastrichtian extinctions {{paleo-reptile-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pistosaurus BW
''Pistosaurus'' (exact etymology uncertain) is an extinct genus of aquatic sauropterygian reptile closely related to plesiosaurs. Fossils have been found in France and Germany, and date to the Middle Triassic. It contains a type species, single species, ''Pistosaurus longaevus. Pistosaurus'' is known as the oldest "subaquatic flying" reptile on earth. The skull of ''Pistosaurus'' generally resembles that of other Triassic sauropterygians. However, there are several synapomorphies that make ''Pistosaurus'' distinguished: the long, slender, snout; the possession of splint-like nasals that are excluded from the external naris; and the posterior extension of the premaxilla to the frontals. Based on synapomorphies such as the small nasals size and the presence of interpterygoid vacuity, ''Pistosaurus'' is more closely related to Plesiosauria than to ''Nothosaurus''. ''Pistosaurus'' is often mistaken with ''Nothosaurus'' and Plesiosauria. ''Nothosaurus'' belongs to the clade Nothosauro ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pistosaurus
''Pistosaurus'' (exact etymology uncertain) is an extinct genus of aquatic sauropterygian reptile closely related to plesiosaurs. Fossils have been found in France and Germany, and date to the Middle Triassic. It contains a single species, ''Pistosaurus longaevus. Pistosaurus'' is known as the oldest "subaquatic flying" reptile on earth. The skull of ''Pistosaurus'' generally resembles that of other Triassic sauropterygians. However, there are several synapomorphies that make ''Pistosaurus'' distinguished: the long, slender, snout; the possession of splint-like nasals that are excluded from the external naris; and the posterior extension of the premaxilla to the frontals. Based on synapomorphies such as the small nasals size and the presence of interpterygoid vacuity, ''Pistosaurus'' is more closely related to Plesiosauria than to '' Nothosaurus''. ''Pistosaurus'' is often mistaken with ''Nothosaurus'' and Plesiosauria. ''Nothosaurus'' belongs to the clade Nothosauroidea from ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Augustasaurus
''Augustasaurus'' is an extinct genus of sauropterygians that lived during the Anisian stage of the Middle Triassic in what is now North America. Only one species is known, ''A. hagdorni'', described in 1997 from fossils discovered in the Favret Formation, Nevada, USA. ''Augustasaurus'' is a pistosauroid estimated to be long. The skull has fang-like teeth, indicating a diet of fish and squid. Its postcranial anatomy is similar to that of future plesiosaurs, with which it visibly shares a common ancestor according to the most recent phylogenetic analyses. The Favret Formation, from which ''Augustasaurus'' is known, contains numerous fossils of marine reptiles dating from the Middle Triassic. The fossils mainly include ichthyosaurs, ''Augustasaurus'' being the only sauropterygian to have been identified in the area. Discovery and naming The first known fossil of ''Augustasaurus'' was discovered in 1993 in Muller Canyon, in the Augusta Mountains located in Nevada, United Sta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pachypleurosauria
Pachypleurosauria is an extinct clade of primitive sauropterygian reptiles from the Triassic period. Pachypleurosaurs vaguely resembled aquatic lizards, with elongate forms ranging in size from , with small heads, long necks, paddle-like limbs, and long, deep tails. The limb girdles are greatly reduced, so it is unlikely these animals could move about on land. The widely spaced peg-like teeth project at the front of the jaws, indicating that these animals fed on fish. In the species '' Prosantosaurus'', it was observed that they fed on small fishes and crustaceans which they devoured entirely and that its teeth regrew after they broke off. This was the first observation of tooth replacement in a European pachypleurosaur, with the only other discovery of such an event having been made in China. Classification Pachypleurosaurs were traditionally included within the Nothosauroidea (Carroll 1988, Benton 2004). In some more recent cladistic classifications, however, (Rieppel 2000), ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cymatosaurus
''Cymatosaurus'' is an extinct genus of pistosauroid or nothosauriform sauropterygian. It is known to have been alive from the Early Triassic to the Middle Triassic period (latest Olenekian to Anisian stages) of Germany Germany, officially the Federal Republic of Germany, is a country in Central Europe. It lies between the Baltic Sea and the North Sea to the north and the Alps to the south. Its sixteen States of Germany, constituent states have a total popu ... and they seem to originate from the Netherlands. It was small to medium-sized for an eosauropterygian, measuring long. See also * Timeline of plesiosaur research References Fossil taxa described in 1894 Early Triassic reptiles of Europe Pistosaurs Triassic sauropterygians Olenekian genus first appearances Anisian genus extinctions Middle Triassic reptiles of Europe Anisian life Sauropterygian genera {{triassic-reptile-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nothosauria
Nothosaurs (superfamily Nothosauroidea) were Triassic marine sauropterygian reptiles. They averaged about in length, with a long body and tail. The feet were paddle-like, and are known to have been webbed in life, to help power the animal when swimming. The neck was quite long, and the head was elongated and flattened, and relatively small in relation to the body. The margins of the long jaws were equipped with numerous sharp outward-pointing teeth, indicating a diet of fish and squid. Taxonomy The Nothosauroidea has been suggested to consist of two suborders, the Pachypleurosauria, which are small primitive forms, and the Nothosauria (including two families Nothosauridae and Simosauridae), which may have evolved from pachypleurosaurs. The relation of pachypleurosaurs to Nothosauroidea is uncertain, as several analyses recover the clade as basal to Eusauropterygia, e.i. the clade formed by Nothosauria and Pistosauroidea, instead as the sister taxon of Nothosauria. Many re ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sauropterygia
Sauropterygia ("lizard flippers") is an extinct taxon of diverse, aquatic diapsid reptiles that developed from terrestrial ancestors soon after the end-Permian extinction and flourished during the Triassic before all except for the Plesiosauria became extinct at the end of that period. The plesiosaurs would continue to diversify until the end of the Mesozoic, when they became extinct as part of the end-Cretaceous mass extinction. Sauropterygians are united by a radical adaptation of their pectoral girdle, adapted to support powerful flipper strokes. Some later sauropterygians, such as the pliosaurs, developed a similar mechanism in their pelvis. Other than being diapsids, their affinities to other reptiles have long been contentious. Sometimes suggested to be closely related to turtles, other proposals have considered them most closely related to Lepidosauromorpha or Archosauromorpha, and/or the marine reptile groups Thalattosauria and Ichthyosauromorpha. Origins an ... [...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] |
Plesiosauria
The Plesiosauria or plesiosaurs are an order or clade of extinct Mesozoic marine reptiles, belonging to the Sauropterygia. Plesiosaurs first appeared in the latest Triassic Period, possibly in the Rhaetian stage, about 203 million years ago. They became especially common during the Jurassic Period, thriving until their disappearance due to the Cretaceous–Paleogene extinction event at the end of the Cretaceous Period, about 66 million years ago. They had a worldwide oceanic distribution, and some species at least partly inhabited freshwater environments. Plesiosaurs were among the first fossil reptiles discovered. In the beginning of the nineteenth century, scientists realised how distinctive their build was and they were named as a separate order in 1835. The first plesiosaurian genus, the eponymous '' Plesiosaurus'', was named in 1821. Since then, more than a hundred valid species have been described. In the early twenty-first century, the number of discoveries ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Basal (phylogenetics)
In phylogenetics, basal is the direction of the ''base'' (or root) of a phylogenetic tree#Rooted tree, rooted phylogenetic tree or cladogram. The term may be more strictly applied only to nodes adjacent to the root, or more loosely applied to nodes regarded as being close to the root. Note that extant taxa that lie on branches connecting directly to the root are not more closely related to the root than any other extant taxa. While there must always be two or more equally "basal" clades sprouting from the root of every cladogram, those clades may differ widely in taxonomic rank, Phylogenetic diversity, species diversity, or both. If ''C'' is a basal clade within ''D'' that has the lowest rank of all basal clades within ''D'', ''C'' may be described as ''the'' basal taxon of that rank within ''D''. The concept of a 'key innovation' implies some degree of correlation between evolutionary innovation and cladogenesis, diversification. However, such a correlation does not make a given ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Early Triassic
The Early Triassic is the first of three epochs of the Triassic Period of the geologic timescale. It spans the time between 251.9 Ma and Ma (million years ago). Rocks from this epoch are collectively known as the Lower Triassic Series, which is a unit in chronostratigraphy. The Early Triassic is the oldest epoch of the Mesozoic Era. It is preceded by the Lopingian Epoch (late Permian, Paleozoic Era) and followed by the Middle Triassic Epoch. The Early Triassic is divided into the Induan and Olenekian ages. The Induan is subdivided into the Griesbachian and Dienerian subages and the Olenekian is subdivided into the Smithian and Spathian subages. The Lower Triassic series is coeval with the Scythian Stage, which is today not included in the official timescales but can be found in older literature. In Europe, most of the Lower Triassic is composed of Buntsandstein, a lithostratigraphic unit of continental red beds. The Early Triassic and partly also the Middle Trias ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Placodontia
Placodonts ("Tablet (pharmacy), tablet tooth, teeth") are an Extinction, extinct order (biology), order of marine reptiles that lived during the Triassic period, becoming extinct at the end of the period. They were part of Sauropterygia, the group that includes Plesiosauria, plesiosaurs. Placodonts were generally between in length, with some of the largest measuring long. The first specimen was discovered in 1830. They have been found throughout central Europe, North Africa, the Middle East and China. Palaeobiology The earliest forms, like ''Placodus'', which lived in the early to middle Triassic, resembled barrel-bodied lizards superficially similar to the marine iguana of today, but larger. In contrast to the marine iguana, which feeds on algae, the placodonts ate Mollusca, molluscs and so their teeth were flat and tough to crush shells. In the earliest periods, their size was probably enough to keep away the top sea predators of the time: the sharks. However, as time passe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
