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Cymbospondylus
''Cymbospondylus'' (a Greek word meaning "boat vertebrae") was a basal early ichthyosaur that lived between the early and middle Triassic period (249-237 million years ago). Previously, the genus was classified as a shastasaurid, but more recent work finds it to be more basal.Motani, R. 1999: Phylogeny of the Ichthyopterygia. Journal of Vertebrate Paleontology. 19 (3): 473 – 496 ''Cymbospondylus'' was a cosmopolitan genus found in Nevada, Europe ( Switzerland, Germanic Basin) and Spitsbergen. History ''Cymbospondylus'' was described from Nevada by Joseph Leidy in 1868 on the basis of several fragmentary vertebrae which he assigned to two different species: ''C. piscosus'' (the type species) and ''C. petrinus''. The University of California, under the direction of John Campbell Merriam and funded by Annie Alexander, conducted extensive fieldwork in the region in the late nineteenth and early twentieth century, following the description of ''Cymbospondylus'', recovering add ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cymbospondylus Petrinus Skull
''Cymbospondylus'' (a Greek word meaning "boat vertebrae") was a basal early ichthyosaur that lived between the early and middle Triassic period (249-237 million years ago). Previously, the genus was classified as a shastasaurid, but more recent work finds it to be more basal.Motani, R. 1999: Phylogeny of the Ichthyopterygia. Journal of Vertebrate Paleontology. 19 (3): 473 – 496 ''Cymbospondylus'' was a cosmopolitan genus found in Nevada, Europe (Switzerland, Germanic Basin) and Spitsbergen. History ''Cymbospondylus'' was described from Nevada by Joseph Leidy in 1868 on the basis of several fragmentary vertebrae which he assigned to two different species: ''C. piscosus'' (the type species) and ''C. petrinus''. The University of California, under the direction of John Campbell Merriam and funded by Annie Alexander, conducted extensive fieldwork in the region in the late nineteenth and early twentieth century, following the description of ''Cymbospondylus'', recovering additio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cymbospondylus Petrinus SW
''Cymbospondylus'' (a Greek language, Greek word meaning "boat Vertebral column, vertebrae") was a Basal (phylogenetics), basal early ichthyosaur that lived between the early and middle Triassic period (249-237 Mya (unit), million years ago). Previously, the genus was classified as a Shastasauridae, shastasaurid, but more recent work finds it to be more basal.Motani, R. 1999: Phylogeny of the Ichthyopterygia. Journal of Vertebrate Paleontology. 19 (3): 473 – 496 ''Cymbospondylus'' was a cosmopolitan genus found in Nevada, Europe (Switzerland, Germanic Basin) and Spitsbergen. History ''Cymbospondylus'' was described from Nevada by Joseph Leidy in 1868 on the basis of several fragmentary vertebrae which he assigned to two different species: ''C. piscosus'' (the type species) and ''C. petrinus''. The University of California, under the direction of John Campbell Merriam and funded by Annie Alexander, conducted extensive fieldwork in the region in the late nineteenth and early twe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ichthyosaur
Ichthyosaurs (Ancient Greek for "fish lizard" – and ) are large extinct marine reptiles. Ichthyosaurs belong to the order known as Ichthyosauria or Ichthyopterygia ('fish flippers' – a designation introduced by Sir Richard Owen in 1842, although the term is now used more for the parent clade of the Ichthyosauria). Ichthyosaurs thrived during much of the Mesozoic era; based on fossil evidence, they first appeared around 250 million years ago ( Ma) and at least one species survived until about 90 million years ago, into the Late Cretaceous. During the Early Triassic epoch, ichthyosaurs and other ichthyosauromorphs evolved from a group of unidentified land reptiles that returned to the sea, in a development similar to how the mammalian land-dwelling ancestors of modern-day dolphins and whales returned to the sea millions of years later, which they gradually came to resemble in a case of convergent evolution. Ichthyosaurs were particularly abundant in the Late Triassic a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cartorhynchus
''Cartorhynchus'' (meaning "shortened snout") is an extinct genus of early ichthyosauriform marine reptile that lived during the Early Triassic epoch, about 248 million years ago. The genus contains a single species, ''Cartorhynchus lenticarpus'', named in 2014 by Ryosuke Motani and colleagues from a single nearly-complete skeleton found near Chaohu, Anhui Province, China. Along with its close relative '' Sclerocormus'', ''Cartorhynchus'' was part of a diversification of marine reptiles that occurred suddenly (over about one million years) during the Spathian substage, soon after the devastating Permian-Triassic extinction event, but they were subsequently driven to extinction by volcanism and sea level changes by the Middle Triassic. Measuring about long, ''Cartorhynchus'' was a small animal with a lizard-like body and a short torso; it probably swam in an eel-like manner at slow speeds. Its limbs bore extensive cartilage and could bend like flippers, which may have allo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Guizhouichthyosaurus
''Guizhouichthyosaurus'' is an extinct genus of ichthyosaur which is known primarily from the Xiaowa Formation of the lower Carnian stage of the Late Triassic in southwest China. The type species of this genus is ''Guizhouichthyosaurus tangae'', of which multiple skeletons are known. It has been reassigned as a species of the genus ''Shastasaurus'' in the past, though it has since been considered distinct. The ichthyosaurs ''Cymbospondylus asiaticus'', named in 2002, and ''Panjiangsaurus epicharis'', named in 2003, are junior synonyms of ''G. tangae''. The genus is also known from the Ladinian-aged Middle Triassic Zhuganpo Formation; additionally, the species ''"Callawayia" wollongangense'' may belong to ''Guizhouichthyosaurus''. ''Guizhouichthyosaurus'' is a large ichthyosaur, typically measuring approximately long with some specimens exceeding . The snout is long and powerful, and there is a low sagittal crest on the rear part of its skull. The tail is bent downwards near its ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thalattoarchon
''Thalattoarchon'' is an extinct genus of ichthyosaur from the Middle Triassic of the western United States. The type species ''Thalattoarchon saurophagis'' (meaning "lizard-eating sovereign of the sea" in Greek) was discovered in Nevada, USA, in 2010 and formally described in 2013. It is known from a single skeleton, holotype FMNH PR 3032, consisting of a partial skull, vertebral column, hip bones, and parts of the hind fins. The total length of ''Thalattoarchon'' is estimated to have been at least . ''Thalattoarchon'' is thought to have been one of the first marine macropredators capable of eating prey that was similar in size to itself, an ecological role that can be compared to that of modern orcas. ''Thalattoarchon'' lived four million years after the first appearance of ichthyosaurs in the Early Triassic and is therefore the oldest known marine reptile to have been an apex predator. It lived eight million years after the Permian-Triassic extinction event, indicating a fast r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mixosaurus
''Mixosaurus'' is an extinct genus of Middle Triassic (Anisian to Ladinian, about 250-240 Mya) ichthyosaur. Its fossils have been found near the Italy–Switzerland border and in South China. The genus was named in 1887 by George H. Baur. The name means "Mixed Lizard", and was chosen because it appears to have been a transitional form between the eel-shaped ichthyosaurs such as ''Cymbospondylus'' and the later dolphin-shaped ichthyosaurs, such as ''Ichthyosaurus''. Baur named ''Mixosaurus'' as a new genus because its forefin was sufficiently different from that of ''Ichthyosaurus''. ''Mixosaurus'' includes 3 species. Previously this number was bigger, and ''Mixosaurus'' was considered as the most common genus of Triassic ichthyosaurs, whose fossils have been found all over the world, including China, Timor, Indonesia, Italy, Spitsbergen, Svalbard, Canada, as well as Alaska and Nevada in the US. Description ''Mixosaurus'' was a small ichthyosaur, measuring between long and w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
John Campbell Merriam
John Campbell Merriam (October 20, 1869 – October 30, 1945) was an American paleontologist, educator, and conservationist. The first vertebrate paleontologist on the West Coast of the United States, he is best known for his taxonomy of vertebrate fossils at the La Brea Tar Pits in Los Angeles, particularly with the genus ''Smilodon'', more commonly known as the sabertooth cat. He is also known for his work to extend the reach of the National Park Service. Biography He was born in Hopkinton, Iowa, the eldest child of postmaster, store proprietor, and American Civil War veteran Charles E. Merriam. His middle name Campbell was his mother's middle name, and the maiden name of his maternal grandmother. Both his father Charles E. Merriam and his paternal uncle Henry C. Merriam had served as officers in the 12th Iowa Infantry, Company K; after capture at the Battle of Shiloh, they were sent to Libby Prison for some time before being returned to the battlefields. Eventually, whe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Humerus
The humerus (; ) is a long bone in the arm that runs from the shoulder to the elbow. It connects the scapula and the two bones of the lower arm, the radius and ulna, and consists of three sections. The humeral upper extremity consists of a rounded head, a narrow neck, and two short processes (tubercles, sometimes called tuberosities). The body is cylindrical in its upper portion, and more prismatic below. The lower extremity consists of 2 epicondyles, 2 processes (trochlea & capitulum), and 3 fossae (radial fossa, coronoid fossa, and olecranon fossa). As well as its true anatomical neck, the constriction below the greater and lesser tubercles of the humerus is referred to as its surgical neck due to its tendency to fracture, thus often becoming the focus of surgeons. Etymology The word "humerus" is derived from la, humerus, umerus meaning upper arm, shoulder, and is linguistically related to Gothic ''ams'' shoulder and Greek ''ōmos''. Structure Upper extremity The upper or pr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dorsal Fin
A dorsal fin is a fin located on the back of most marine and freshwater vertebrates within various taxa of the animal kingdom. Many species of animals possessing dorsal fins are not particularly closely related to each other, though through convergent evolution they have independently evolved external superficial fish-like body plans adapted to their marine environments, including most numerously fish, but also mammals such as cetaceans (whales, dolphins, and porpoises), and even extinct ancient marine reptiles such as various known species of ichthyosaurs. Most species have only one dorsal fin, but some have two or three. Wildlife biologists often use the distinctive nicks and wear patterns which develop on the dorsal fins of large cetaceans to identify individuals in the field. The bony or cartilaginous bones that support the base of the dorsal fin in fish are called ''pterygiophores''. Functions The main purpose of the dorsal fin is to stabilize the animal against rollin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ophthalmosaurus
''Ophthalmosaurus'' (meaning "eye lizard" in Greek) is an ichthyosaur of the Jurassic period (165–150 million years ago). Possible remains from the Cretaceous, around 145 million years ago, are also known. It was a relatively medium-sized ichthyosaur, measuring long and weighing . Named for its extremely large eyes, it had a jaw containing many small but robust teeth. Major fossil finds of this genus have been recorded in Europe with a second species possibly being found in North America. Description ''Ophthalmosaurus'' was a medium-sized ichthyosaur, measuring long and weighing . It had a robust, streamlined body that was nearly as wide as it was tall in frontal view. Like other derived ichthyosaurs ''Ophthalmosaurus'' had a powerful tail ending in a pronounced bi-lobed caudal fluke whose lower half was formed around the caudal spine whereas the upper lobe was made up entirely from soft tissue. The limbs of ''Ophthalmosaurus'' were short and rounded with the forelimbs bein ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dentition
Dentition pertains to the development of teeth and their arrangement in the mouth. In particular, it is the characteristic arrangement, kind, and number of teeth in a given species at a given age. That is, the number, type, and morpho-physiology (that is, the relationship between the shape and form of the tooth in question and its inferred function) of the teeth of an animal. Animals whose teeth are all of the same type, such as most non-mammalian vertebrates, are said to have '' homodont'' dentition, whereas those whose teeth differ morphologically are said to have '' heterodont'' dentition. The dentition of animals with two successions of teeth (deciduous, permanent) is referred to as ''diphyodont'', while the dentition of animals with only one set of teeth throughout life is ''monophyodont''. The dentition of animals in which the teeth are continuously discarded and replaced throughout life is termed ''polyphyodont''. The dentition of animals in which the teeth are set in so ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
