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Cimoliasauridae
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 Streptosauri ... [...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. '' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cimoliasaurus
''Cimoliasaurus'' was a plesiosaur that lived during the Late Cretaceous (Maastrichtian) of New Jersey. It grew up to long and weighed up to . Etymology The name is derived from the Greek , meaning "white chalk", and , meaning "lizard", in reference to the fact that the deposits in which it was found bear a superficial resemblance to the chalk deposits of the Western Interior Seaway. Taxonomic history The name ''Cimoliasaurus magnus'' was coined by Joseph Leidy for ANSP 9235, one anterior and 12 posterior cervical vertebrae collected in Maastrichtian-aged greensand deposits in Burlington County, New Jersey. In his catalogue of plesiosaur and ichthyosaur specimens preserved in the NHM, the British zoologist Richard Lydekker referred several Jurassic and Cretaceous plesiosaur species to ''Cimoliasaurus'', including the new species ''C. richardsoni'' (now considered a species of ''Cryptoclidus'') and ''C. cantabrigiensis'', as well as ''Colymbosaurus'' and a number of pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hauterivian
The Hauterivian is, in the geologic timescale, an age in the Early Cretaceous Epoch or a stage in the Lower Cretaceous Series. It spans the time between 132.9 ± 2 Ma and 129.4 ± 1.5 Ma (million years ago). The Hauterivian is preceded by the Valanginian and succeeded by the Barremian.See Gradstein ''et al.'' (2004) for a detailed geologic timescale Stratigraphic definitions The Hauterivian was introduced in scientific literature by Swiss geologist Eugène Renevier in 1873. It is named after the Swiss town of Hauterive at the shore of Lake Neuchâtel. The base of the Hauterivian is defined as the place in the stratigraphic column where the ammonite genus '' Acanthodiscus'' first appears. A reference profile for the base (a GSSP) was officially ratified by the International Union of Geological Sciences in December of 2019, and is placed in La Charce, France. The top of the Hauterivian (the base of the Barremian) is at the first appearance of ammonite species ''Spitidis ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cardiocorax
''Cardiocorax'' is an extinct genus of elasmosaurid known from the Late Cretaceous (early Maastrichtian stage) Mocuio Formation of Namibe Province, southern Angola. It contains a single species, ''Cardiocorax mukulu''. Its length is estimated at . Discovery ''Cardiocorax'' is known from the holotype MGUAN PA103 which consists of a complete pectoral and pelvic girdle, five neck and one back vertebrae, a partial forelimb including the humerus, radius bone, ulna and isolated phalanges, and several dorsal ribs. A second specimen was also referred to the species, MGAUN PA270, a more complete articulated pelvic girdle and a single hind limb. Both specimens are housed at the Museu de Geologia da Universidade Agostinho Neto in Luanda. The specimens were discovered at Bench 19 locality, about 7 meters from each other, in Bentiaba of the Namibe Province. They were collected from the Mocuio Formation of the Sāo Nicolau Group of Namibe Basin, dating to the early Maastricht ... [...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] |
Futabasaurus
''Futabasaurus'' is a genus of plesiosaur from the Late Cretaceous of Fukushima, Japan. It was described and named in 2006, and was assigned to the family Elasmosauridae. The genus contains one species, ''F. suzukii''. Description The size of ''Futabasaurus'' has been estimated within the range of in length and in body mass. It can be distinguished from other elasmosaurids by the following characteristics: there is a long distance between the eye sockets and nostrils; the interclavicles and clavicles are fused, and the anterior edge is bent; the humerus is relatively long; and the femora are slim and show prominent muscle scars. Discovery and naming ''Futabasaurus'' is the first elasmosaurid found in Japan. It was originally known as either "Wellesisaurus sudzuki" or "Futaba-ryu" before publication. The type specimen of ''Futabasaurus'' was found in the Irimazawa Member of the Tamayama Formation, in the Futaba Group of Fukushima Prefecture, Japan. The rocks in which i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aphrosaurus
''Aphrosaurus'' (meaning "sea-foam lizard") is an extinct genus of plesiosaur from the Late Cretaceous. The type species is ''Aphrosaurus furlongi'', named by Welles in 1943. ''Aphrosaurus furlongi'' was discovered in the Panoche Hills of Fresno County, California in 1939 by rancher Frank C. Piava and named after University of California Berkeley field assistant and specimen preparator Eustace Furlong.Hilton, Richard P., ''Dinosaurs and Other Mesozoic Animals of California'', University of California Press, Berkeley 2003 , at page 100. See also * Timeline of plesiosaur research * List of plesiosaur genera 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 ... Notes References * Carroll, R.L. (1988). ''Vertebrate Paleontology and Evolution''. W.H. Freeman and Company External ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Terminonatator
''Terminonatator'' (meaning "last swimmer") is a genus of 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 based on 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, 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 neural arches are fused to their vertebrae, although incomplete fusion elsewhere indicates it was a young adult. It would have been small as an a ... [...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 original ... [...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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hydrotherosaurus
''Hydrotherosaurus'' (meaning "water beast lizard") is an extinct genus of elasmosaurid plesiosaur from the Upper Cretaceous (Maastrichtian stage) Moreno Formation of Fresno County, California, USA. The only known species, ''H. alexandrae'', was named for its discoverer, Annie Montague Alexander, by Samuel Paul Welles. Description ''Hydrotherosaurus'' measured approximately in length. It has one of the longest necks relative to total length among elasmosaurids, with 60 vertebrae in total. It had a small head that measured about long, a streamlined body, and four large flippers that were specially designed to help the huge animal balance, move, and accelerate itself. See also * List of plesiosaur genera * Timeline of plesiosaur research This timeline of plesiosaur research is a chronologically ordered list of important fossil discoveries, controversies of interpretation, taxonomic revisions, and cultural portrayals of plesiosaurs, an order of marine reptiles that flou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fluvionectes
''Fluvionectes'' (meaning "river swimmer", from both Latin and Greek) is a genus of elasmosaurid plesiosaur found in the Dinosaur Park Formation in Alberta, Canada. It is known from a holotype, which includes parts of the trunk area, and from a much larger specimen referred to this taxon. Description The holotype of ''Fluvionectes'' reached long and weighed . A much larger specimen indicates that this taxon may have reached in maximum body length. Classification The describers placed ''Fluvionectes'' in the Elasmosauridae, in a clade with ''Albertonectes'', ''Nakonanectes'', ''Styxosaurus'', and ''Terminonatator'', which by definition places it in the Elasmosaurinae subfamily. Paleobiology ''Fluvionectes'' appears to have been a freshwater (and possibly brackish water Brackish water, sometimes termed brack water, is water occurring in a natural environment that has more salinity than freshwater, but not as much as seawater. It may result from mixing seawater (salt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
