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Elasmosaur
Elasmosauridae is an extinct family of plesiosaurs, often called elasmosaurs. They had the longest necks of the plesiosaurs and existed from the Hauterivian to the Maastrichtian stages of the Cretaceous, and represented one of the two groups of plesiosaurs present at the end of the Cretaceous alongside Polycotylidae. Their diet mainly consisted of crustaceans and molluscs. Description The earliest elasmosaurids were mid-sized, about . In the Late Cretaceous, elasmosaurids grew as large as , such as '' Styxosaurus'', ''Albertonectes'', and '' Thalassomedon''. Their necks were the longest of all the plesiosaurs, with anywhere between 32 and 76 (''Albertonectes'') cervical vertebrae. They weighed up to several tons. Classification Early three-family classification Though Cope had originally recognized ''Elasmosaurus'' as a plesiosaur, in an 1869 paper he placed it, with ''Cimoliasaurus'' and ''Crymocetus'', in a new order of sauropterygian reptiles. He named the group Streptosa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Elasmosaurus Platyurus
''Elasmosaurus'' (;) is a genus of plesiosaur that lived in North America during the Campanian stage of the Late Cretaceous period, about 80.5million years ago. The first specimen was discovered in 1867 near Fort Wallace, Kansas, US, and was sent to the American paleontologist Edward Drinker Cope, who named it ''E.platyurus'' in 1868. The Generic name (biology), generic name means "thin-plate reptile", and the specific name (zoology), specific name means "flat-tailed". Cope originally reconstructed the skeleton of ''Elasmosaurus'' with the skull at the end of the tail, an error which was made light of by the paleontologist Othniel Charles Marsh, and became part of their "Bone Wars" rivalry. Only one incomplete ''Elasmosaurus'' skeleton is definitely known, consisting of a fragmentary skull, the spine, and the pectoral girdle, pectoral and pelvic girdles, and a single species is recognized today; other species are now considered invalid or have been moved to other genera. Measuring ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Elasmosaurus
''Elasmosaurus'' (;) is a genus of plesiosaur that lived in North America during the Campanian stage of the Late Cretaceous period, about 80.5million years ago. The first specimen was discovered in 1867 near Fort Wallace, Kansas, US, and was sent to the American paleontologist Edward Drinker Cope, who named it ''E.platyurus'' in 1868. The generic name means "thin-plate reptile", and the specific name means "flat-tailed". Cope originally reconstructed the skeleton of ''Elasmosaurus'' with the skull at the end of the tail, an error which was made light of by the paleontologist Othniel Charles Marsh, and became part of their "Bone Wars" rivalry. Only one incomplete ''Elasmosaurus'' skeleton is definitely known, consisting of a fragmentary skull, the spine, and the pectoral and pelvic girdles, and a single species is recognized today; other species are now considered invalid or have been moved to other genera. Measuring in length and in body mass, ''Elasmosaurus'' would have ha ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plesioelasmosaurus
''Plesioelasmosaurus'' is an extinct genus of elasmosaurid plesiosaur from the Late Cretaceous (middle Cenomanian) Greenhorn Limestone of Kansas, United States. The genus contains a single species, ''P. walkeri'', known from a partial skeleton. Discovery and naming The holotype specimen, UNSM 50134, was discovered by Joe Purzer, an oil field geologist, in 1931 near the town of Holyrood, Kansas. He notified George F. Sternberg and Myrl V. Walker, and the excavation of the specimen commenced later in the year. It was collected over a period of ten days in October 1931. The specimen became known as the 'Holyrood elasmosaur' and was eventually sold to the University of Nebraska State Museum in 1935, where it was prepared and placed into storage. Everhart (2007) noted that Harold Ehler used photographs of the holotype to identify the type locality, but no further remains of ''Plesioelasmosaurus'' resulted from Ehler's discovery. The holotype consists of both ilia, partial hind ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Styxosaurus
''Styxosaurus'' is a genus of plesiosaur of the family Elasmosauridae. ''Styxosaurus'' lived during the Campanian age of the Cretaceous period. Two species are known: ''S. snowii'' and ''S. browni''. Description ''Styxosaurus'' was a large plesiosaur, one of several species of a group collectively called elasmosaurs that appeared in the Late Cretaceous. Elasmosaurs typically have a neck that is at least half the length of the body, and composed of 60-72 vertebrae. ''Styxosaurus'' was a large elasmosaur with a long neck. It reached in length and in body mass. Its sharp teeth were conical and were adapted to puncture and hold rather than to cut; like other plesiosaurs, ''Styxosaurus'' swallowed its food whole. Discovery The holotype specimen of ''Styxosaurus snowii'' was described by S.W. Williston from a complete skull and 20 vertebrae. Another more complete specimen - SDSMT 451 was discovered near Iona, South Dakota, also in the US, in 1945. The specimen was originally ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scanisaurus
''Scanisaurus'' is a dubious genus of plesiosaur that lived in what is now Sweden and Russia during the Campanian stage of the Late Cretaceous period. The name ''Scanisaurus'' means " Skåne lizard", Skåne being the southernmost province of Sweden, where a majority of the fossils referred to the genus have been recovered. The genus contains one species, ''S. nazarowi'', described in 1911 by Nikolay Bogolyubov as a species of ''Cimoliasaurus'' based on a single vertebral centrum discovered near Orenburg, Russia. ''S. nazarowi'' was separated into its own genus by Per-Ove Persson in 1959 after several differences were observed between the Russian centra and new fossils from Skåne and the type species of ''Cimoliasaurus''. Due to the limited type material and the lack of diagnostic features in the Swedish fossils confidently separating ''Scanisaurus'' from other Late Cretaceous elasmosaurids, the genus is of questionable validity, though it continues to be used in practice. ''S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kawanectes
''Kawanectes'' (meaning "Kawas swimmer") is a genus of elasmosaurid plesiosaur, a type of long-necked marine reptile, that lived in the marginal marine ( estuarine) environment of Late Cretaceous Patagonia. It contains one species, ''K. lafquenianum'', described in 2016 by O'Gorman. Description At in body length and in body mass, ''Kawanectes'' was small for an elasmosaurid. It belongs to the "non-elongated" group of elasmosaurids, meaning that its cervical vertebrae are not extremely lengthened, neither do they show great variability in length. The MCS specimen preserves 15 cervical vertebrae and 15 dorsal vertebrae, while the holotype preserves 10 caudal vertebrae; the true number of cervical and caudal vertebrae is unknown due to the incompleteness of the specimens. A combination of traits can be used to distinguish ''Kawanectes'' from all other elasmosaurids: the centra of the vertebrae are wider than they are long; the projections known as the parapophyses on the ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nakonanectes
''Nakonanectes bradti'' is an elasmosaurid plesiosaur of the late Cretaceous found in 2010 the state of Montana in the United States. It is one of the most recently known elasmosaurids to have lived in North America. Unlike other elasmosaurids, it has a relatively short neck. Description In November 2010, hunter David Bradt stumbled on an elasmosaur fossil in a canyon on the Charles M. Russell National Wildlife Refuge. The specimen proved to be a new, short-necked species of elasmosaur, subsequently named ''Nakonanectes bradti''. The type specimen, MOR 3072, was nearly complete. This included the skull, a part not often found intact in Elasmosauridae fossils. Other elements of the fossil included the anterior cervical vertebrae, partial dorsal and caudal vertebrae, incomplete fore and hind limbs, gastralia, partial pectoral and pelvic girdles, and ribs. The fossil was found in the Bearpaw Formation, a late Campanian/early Maastrichtian rock, making it one of the last known el ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Albertonectes
''Albertonectes'' is an extinct genus of elasmosaurid plesiosaur known from the Late Cretaceous (middle upper Campanian stage) Bearpaw Formation of Alberta, Canada. It contains a single species, ''Albertonectes vanderveldei''. ''Albertonectes'' is the longest elasmosaur, and more generally plesiosaur, known to date both in neck and total body length. Discovery ''Albertonectes'' is known solely from the holotype TMP 2007.011.0001, a complete well preserved postcranial skeleton housed at the Royal Tyrrell Museum of Palaeontology in Drumheller, Alberta. Elements include all 132 vertebrae from the atlas-axis complex to fused tip of the tail vertebrae, complete pectoral and incomplete pelvic girdles, almost complete forelimbs and hindlimbs, disarticulated ribs, a gastralium, and at least 97 associated gastroliths. TMP 2007.011.0001 was discovered during mining for gem-quality ammonite shell called Ammolite by Korite International Ltd. about 150 meters south of the St. M ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Terminonatator
''Terminonatator'' (meaning "last swimmer") is a genus of elasmosauridae, elasmosaurid plesiosaur from the Late Cretaceous of Saskatchewan, Canada. It is known from a skull and partial skeleton from a young adult, found in the Campanian-age Bearpaw Formation near Notukeu Creek in Ponteix. ''Terminonatator'' is currently one of the youngest plesiosaurs from the Western Interior Seaway. Description ''Terminonatator'' is holotype, based on Royal Saskatchewan Museum, RSM P2414.1, a skull and partially articulated incomplete skeleton found high in the Bearpaw Formation. Tamaki Sato, who named and described the specimen in 2003 in paleontology, 2003, used the genus name to emphasize its lateness in the fossil record, and the species epithet ''ponteixensis'' for Ponteix. Only one species has been described: the type species ''T. ponteixensis''. RSM P2414.1 appears to represent an adult, because the vertebral arch, neural arches are fused to their vertebrae, although incomplete fus ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eromangasaurus
''Eromangasaurus'' is an extinct genus of elasmosaurid known from northern Queensland of Australia. Description ''Eromangasaurus'' is a medium-sized elasmosaurid, measuring in length and in body mass. It is known from the holotype QM F11050, a nearly complete but badly crushed skull and mandible. It was collected in Maxwelton, from the Toolebuc Formation of the Eromanga Basin, dating to the late Albian stage of the Early Cretaceous, about 103 million years ago. Sven Sachs mentioned some referred material from the same locality as the holotype, QM F12216-19, an anterior cervical vertebra and QM F12217&2, associated posterior cervical vertebrae. Discovery ''Eromangasaurus'' was first named by Benjamin P. Kear in 2005 and the type species is ''Eromangasaurus australis''. Benjamin P. Kear originally named QM F11050 as ''Eromangasaurus carinognathus''. However, earlier in 2005, Sven Sachs named a second species of '' Tuarangisaurus'', ''Tuarangisaurus austral ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mauisaurus
''Mauisaurus'' ("Māui lizard") is a dubious genus of plesiosaur that lived during the Late Cretaceous period in what is now New Zealand. Numerous specimens have been attributed to this genus in the past, but a 2017 paper restricts ''Mauisaurus'' to the lectotype and declares it a ''nomen dubium''. Description Little can be said about the appearance of ''Mauisaurus'' as the only known material is an undiagnostic, fragmentary pelvic area and flippers. The lectotype material shows some features that may indicate aristonectine affinities, but simultaneously possesses anatomical features more consistent with non-aristonectine elasmosaurs. Etymology ''Mauisaurus'' gets its name from the New Zealand Māori mythological demigod, Māui. Māui is said to have pulled New Zealand up from the seabed using a fish hook, thus creating the country. Thus, ''Mauisaurus'' means "''Māui lizard''". ''Mauisaurus'' gets its scientific last name from its original finder, Julius von Haast, who fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Libonectes
''Libonectes'' is an extinct genus of sauropterygian reptile belonging to the plesiosaur order. It is known from specimens found in the Britton Formation of Texas (USA) and the Akrabou Formation of Morocco, which have been dated to the lower Turonian stage of the late Cretaceous period. Nomenclature The prefix "''libo''" comes from Greek, and means "southern," translated to English. "''Nectes''," the suffix, is also from Greek, and translates to "swimmer." In its entirety, ''Libonectes'' can be interpreted as "southern swimmer." ''Libonectes'' was an elasmosaurid plesiosaur, with many specimens unearthed in southern parts of North America- as a result, it was labeled with such a name as described in the preceding sentence. C.G. Morgan is credited with the discovery of the first ''Libonectes'' fossils, and it was for this reason that ''morgani'' was chosen as its binomial name. Description The animal was very similar to the related '' Thalassomedon'', though the structure of th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
