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Eileanchelys Waldmani
''Eileanchelys'' is an extinct genus of primitive turtle from the Middle Jurassic (Bathonian) period some 164 million years ago of Britain. Only one species is recorded, ''Eileanchelys waldmani''. It is the best-represented turtle from the Middle Jurassic, because of the amount of specimens that can be assigned to it. The turtle is also one of the oldest turtles ever found to be aquatic, and might represent a milestone in turtle evolution. Discovery and naming In 2009, two specimens from the National Museums of Scotland, Edinburgh, including NMS G 2004.31.15 and NMS G 2004.31.16a–f, were found to differ from other turtles from the area and age. It was decided that they represented a new genus and species, and were named ''Eileanchelys waldmani'' by Jérémy Anquetin and his colleagues. The specimen NMS G 2004.31.15 was designated as the holotype, and NMS G 2004.31.16a-f, the paratypes. NMS G 2004.31.16 includes at least five, and possibly six, different individuals, all in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Middle Jurassic
The Middle Jurassic is the second epoch of the Jurassic Period. It lasted from about 174.1 to 163.5 million years ago. Fossils of land-dwelling animals, such as dinosaurs, from the Middle Jurassic are relatively rare, but geological formations containing land animal fossils include the Forest Marble Formation in England, the Kilmaluag Formation in Scotland,British Geological Survey. 2011Stratigraphic framework for the Middle Jurassic strata of Great Britain and the adjoining continental shelf: research report RR/11/06 British Geological Survey, Keyworth, Nottingham. the Daohugou Beds in China, the Itat Formation in Russia, and the Isalo III Formation of western Madagascar. Paleogeography During the Middle Jurassic Epoch, Pangaea began to separate into Laurasia and Gondwana, and the Atlantic Ocean formed. Eastern Laurasia was tectonically active as the Cimmerian plate continued to collide with Laurasia's southern coast, completely closing the Paleo-Tethys Ocean. A subduction zone ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Testudines
Turtles are an order (biology), order of reptiles known as Testudines, characterized by a special turtle shell, shell developed mainly from their ribs. Modern turtles are divided into two major groups, the Pleurodira (side necked turtles) and Cryptodira (hidden necked turtles), which differ in the way the head retracts. There are 360 living and recently extinct species of turtles, including land-dwelling tortoises and freshwater terrapins. They are found on most continents, some islands and, in the case of sea turtles, much of the ocean. Like other Amniote, amniotes (reptiles, birds, and mammals) they breathe air and do not lay eggs underwater, although many species live in or around water. Turtle shells are made mostly of bone; the upper part is the domed Turtle shell#Carapace, carapace, while the underside is the flatter plastron or belly-plate. Its outer surface is covered in scale (anatomy), scales made of keratin, the material of hair, horns, and claws. The carapace bon ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Meiolania Platyceps
''Meiolania'' ("small roamer") is an extinct genus of meiolaniid stem-turtle native to Australasia from the Middle Miocene to Late Pleistocene and possibly Holocene. It is best known from fossils found on Lord Howe Island, though fossils are known from mainland Australia, New Caledonia, and possibly Vanuatu and Fiji. Taxonomy The genus was erected in 1886 based on remains found on Lord Howe Island, which Richard Owen assigned to the two species ''M. platyceps'' and ''M. minor'' (now a synonym of the former). These were the first good meiolaniid remains, and were used to show that the first known remains of a related animal, a species from Queensland now known as '' Ninjemys oweni'' (which was assigned to ''Meiolania'' until 1992), did not belong to lizards as initially thought, but to turtles. Woodward sank '' Niolamia argentina'' into ''Meiolania'', but this was not accepted by later authors. The species of the genus may be summarized as In New Caledonia, ''M. mack ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Condorchelys Antiqua
''Condorchelys'' was a genus of stem turtle from Early Jurassic Cañadon Asfalto Formation of Argentina. Only one species is described, ''Condorchelys antiqua''.Sterli, 2008 References Bibliography * Prehistoric turtle genera Bajocian life Aalenian life Toarcian life Early Jurassic reptiles of South America Middle Jurassic reptiles of South America Jurassic Argentina Fossils of Argentina Cañadón Asfalto Formation Fossil taxa described in 2008 {{Jurassic-reptile-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kayentachelys Aprix
''Kayentachelys'' ("Kayenta turtle") is an extinct genus of turtle known only from the "silty facies" of the Lower Jurassic Kayenta Formation in northeastern Arizona on the lands of the Navajo Nation. History of discovery and significance The earliest mention of turtles from the Kayenta Formation in the literature is within the description of the ornithischian dinosaur '' Scutellosaurus'' by Colbert (1981). These first specimens were collected during the 1970s and early 1980s by field parties from the Museum of Northern Arizona (MNA) and the Museum of Comparative Zoology (MCZ) at Harvard University. Specimens from these field excursions were used to establish the taxon ''Kayentachelys'' in 1987, and it is an MNA specimen (MNA V1558) which was designated as the holotype of the taxon. During the early 1980s, addition turtle specimens from the Kayenta Formation were collected by field parties from the University of California Museum of Paleontology (UCMP), which were repor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Proterochersis Robusta
''Proterochersis'' is an extinct genus of turtle from the Late Triassic period (Norian stage) of Europe. It is known from a large number of fossils uncovered in Germany and Poland.Fraas E (1913)"''Proterochersis'', eine pleurodire Schildkröte aus dem Keuper" ''Jahreshefte des Vereins für Vaterländische Naturkunde in Württemberg'' 69: p. 13–30Szczygielski T & Sulej T (2016). "Revision of the Triassic European turtles ''Proterochersis'' and ''Murrhardtia'' (Reptilia, Testudinata, Proterochersidae), with the description of new taxa from Poland and Germany". ''Zoological Journal of the Linnean Society'' 177(2): pp. 395–427. Szczygielski1 T, Słowiak J & Dróżdż1 D (2018). "Shell variability in the stem turtles ''Proterochersis'' spp". ''PeerJ'' 6: The genus was named from fossil remains from Germany in 1913 by Fraas, who recognized two species: ''P. robusta'' (type species) and ''P. intermedia''. Since then, Szczygielski and Sulej have found that the differences described by F ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Australochelys Africanus
''Australochelys'' is an extinct genus of rhaptochelydian turtle. It is known from one species, ''A. africanus'', that came from the Elliot Formation of South Africa. The holotype of ''Australochelys'' consists of only a skull and a fragment of the carapace, which shows both primitive and derived features. Like ''Proganochelys'', ''Australochelys'' has large orbits and a ventral basioccipital tubercle, but like derived turtles such as casichelydians, a group containing Cryptodira and Pleurodira, it possesses a sutured basipterygoidal attachment, and a middle ear region partially enclosed laterally. These characteristics show that ''Australochelys'' is more closely related to casichelydians than to ''Proganochelys'', and together with the former, it makes up Rhaptochelydia. The skull of ''Australochelys'' shows that an advanced hearing mechanism of turtles evolved before the appearance of modern turtles. Etymology ''Australochelys africanus'' was named in 1994 by Eugen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Proganochelys Quenstedti
''Proganochelys'' is an extinct, primitive stem-turtle that has been hypothesized to be the sister taxon to all other turtles creating a monophyletic group, the ''Casichelydia''. ''Proganochelys'' was named by Georg Baur in 1887 as the oldest turtle in existence at the time. The name ''Proganochelys'' comes from the Greek word ''ganos'' meaning 'brightness', combined with prefix ''pro'', 'before', and Greek base ''chelys'' meaning 'turtle'. ''Proganochelys'' is believed to have been around 1 meter in size and herbivorous in nature. ''Proganochelys'' was known as the most primitive stem-turtle for over a century, until the novel discovery of ''Odontochelys'' in 2008. ''Odontochelys'' and ''Proganochelys'' share unique primitive features that are not found in ''Casichelydia'', such as teeth on the pterygoid and vomer and a plate-like coracoid. ''Proganochelys'' is the oldest stem-turtle species with a complete shell discovered to date, known from fossils found in Germany, Switzerla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
