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Pachypleurosauria
left, 220px, '' Pachypleurosaurus'' Pachypleurosauria is an extinct clade of primitive sauropterygian reptiles that vaguely resembled aquatic lizards, and were limited to the Triassic period. They were elongate animals, 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, the only other discovery of such an event was made in China. Classification Pachypleurosaurs were originally and are often still included within the Nothosauroidea (Carroll 1988, Benton 2004). In some more rece ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nothosaur
Nothosaurs (order Nothosauroidea) were Triassic marine sauropterygian reptiles that may have lived like seals of today, catching food in water but coming ashore on rocks and beaches. They averaged about in length, with a long body and tail.F. v. Huene. 1956. Paläontologie und Phylogenie der Niederen Tetrapoden aleontology and Phylogeny of the Lower Tetrapods ''VEB Gustav Fischer Verlang, Jena'' 1-716 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 consist of two suborders: * Pachypleurosauria, small primitive forms, and * Nothosauria (including two families Nothosauridae and Simosauridae), which evolved from pachypleurosaurs. The placement of pachyple ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sauropterygia
Sauropterygia ("lizard flippers") is an extinct taxon of diverse, aquatic 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. 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. Uniquely among reptiles, sauropterygians moved their tail vertically like modern cetaceans and sirenians. Origins and evolution The earliest sauropterygians appeared about 247 million years ago (Ma), at the start of the Middle Triassic: the first definite sauropterygian with exact stratigraphic datum lies within the Spathian division of the Olenekian era in South China. Early examples were small (around 60 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plesiosaur
The Plesiosauria (; Greek: πλησίος, ''plesios'', meaning "near to" and ''sauros'', meaning "lizard") 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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anarosaurus
''Anarosaurus'' is an extinct genus of pachypleurosaurs that lived in the Middle Triassic period (Anisian) and has been found in the Jena Formation and the Karlstadt Formation of Germany and the Winterswijk Quarry ( Lower Muschelkalk) of The Netherlands. Two species are known: ''A. pumilio'' (the type species) and ''A. heterodontus''. The holotype of ''A. pumilio'' was originally housed at the Institut und Museum fur Geologie und Palaontologie, Georg-August-Universitat, Gottingen, but can no longer be located today because it was lost or destroyed during World War II. ''Anarosaurus'' was a small reptile with an estimated body length of . See also * List of plesiosaurs This list of plesiosaurs is a comprehensive listing of all genera that have ever been included in the order Plesiosauria, excluding purely vernacular terms. The list includes all commonly accepted genera, but also genera that are now considered inv ... References Triassic plesiosaurs Extinct animals of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hanosaurus
''Hanosaurus'' is an extinct genus of marine reptiles that existed during the Triassic period in what is now China. It was described by Young in 1972, and the type species is ''Hanosaurus hupehensis''. Its affinities are unclear; it has been both described as a member of the Pachypleurosauria and as a sister group In phylogenetics, a sister group or sister taxon, also called an adelphotaxon, comprises the closest relative(s) of another given unit in an evolutionary tree. Definition The expression is most easily illustrated by a cladogram: Taxon A and t ... of that group. It was a small animal, with specimens measuring long in total body length, which likely fed on soft-bodied prey. References See also Triassic sauropterygians Fossil taxa described in 1972 Fossils of China Taxa named by Yang Zhongjian Sauropterygian genera {{triassic-reptile-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dactylosaurus
''Dactylosaurus'' is a genus of nothosaur in the family Pachypleurosauridae. Along with '' Anarosaurus'', ''Dactylosaurus'' was one of the earliest known pachypleurosaurs to come from Europe.Lepidosauromorpha: Pachypleurosauridae: Dactylosaurus & Anarosaurus Palaeos.com. Last accessed 2008-07-04. Etymology ''Dactylosaurus'' comes from the ' (), "" and ' (), meaning "" or ...[...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 arch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Limb Girdles
Limb may refer to: Science and technology *Limb (anatomy), an appendage of a human or animal *Limb, a large or main branch of a tree *Limb, in astronomy, the curved edge of the apparent disk of a celestial body, e.g. lunar limb *Limb, in botany, the border or upper spreading part of a petal or sepal *Limb, in a measuring instrument, the graduated edge of a circle or arc Music * ''Limb'' (album), by Foetus, 2009 *''Limb'', an album by Justin Clayton, 1999 *"Limbs", a song by Emma Pollock from ''Watch the Fireworks'', 2007 *Limb Music, a German record label Other uses *Limb (surname), a list of people *Limb McKenry (1888–1956), American baseball pitcher *Limb Brook, a stream in Sheffield, South Yorkshire, England *Limbs Dance Company, in Auckland, New Zealand *Limbs, in archery, the upper and lower working parts of the bow; see recurve bow *Bresso Airfield, Bresso, Italy (ICAO code) *Limbu script (ISO 15924 code) See also * Limb darkening, an optical effect seen in stars * Limbe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fish
Fish are aquatic, craniate, gill-bearing animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish as well as various extinct related groups. Approximately 95% of living fish species are ray-finned fish, belonging to the class Actinopterygii, with around 99% of those being teleosts. The earliest organisms that can be classified as fish were soft-bodied chordates that first appeared during the Cambrian period. Although they lacked a true spine, they possessed notochords which allowed them to be more agile than their invertebrate counterparts. Fish would continue to evolve through the Paleozoic era, diversifying into a wide variety of forms. Many fish of the Paleozoic developed external armor that protected them from predators. The first fish with jaws appeared in the Silurian period, after which many (such as sharks) became formidable marine predators rather than just the prey of arthrop ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Swissinfo
SWI swissinfo.ch is a multilingual news and information platform produced by the Swiss Broadcasting Corporation (SRG SSR). Its content is Swiss-centred, with top priority given to in-depth information on politics, the economy, the arts, science, education, and direct democracy. Switzerland's international political, economic and cultural relations are other key points of focus. The website is available in ten languages. History In the mid-1990s, economic circumstances forced swissinfo.ch to take a new strategic direction. The internet was advancing fast, heralding a new era for the producing journalists and the Swiss Radio International (SRI) audience alike. The German, French, English and Portuguese sites went online in 1999. The Italian, Japanese and Spanish sites followed in 2000, with Arabic going live on 1 February 2001 and Chinese in September of the same year. Within just two years, the internet platform for expatriate Swiss was already better known than SRI's short-wav ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
