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Muraenosaurus
''Muraenosaurus'' (from the Latin "'' Muraena''" meaning "eel" and "''Sauros''" meaning lizard) is an extinct genus of cryptoclidid plesiosaur reptile from the Oxford Clay of Southern England. The genus was given its name due to the eel-like appearance of the long neck and small head. ''Muraenosaurus'' grew up to in length and lived roughly between 160 Ma (million years ago) and 164 Ma in the Callovian of the middle Jurassic. Charles E. Leeds collected the first ''Muraenosaurus'' which was then described by H. G. Seeley.Seeley, HG. 1874. On ''Murænosaurus Leedsii'', a Plesiosaurian from the Oxford Clay. Part I. ''Quarterly Journal of the Geological Society'' 30: 197-208. The specimen may have suffered some damage due to the casual style of Charles Leeds’ collection. The first Muraenosaur was recovered with pieces missing from the skull and many of the caudal vertebrae absent. Because the animal was described from Charles Leeds’ collection it was given the name ''Muraeno ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Muraenosaurus
''Muraenosaurus'' (from the Latin "'' Muraena''" meaning "eel" and "''Sauros''" meaning lizard) is an extinct genus of cryptoclidid plesiosaur reptile from the Oxford Clay of Southern England. The genus was given its name due to the eel-like appearance of the long neck and small head. ''Muraenosaurus'' grew up to in length and lived roughly between 160 Ma (million years ago) and 164 Ma in the Callovian of the middle Jurassic. Charles E. Leeds collected the first ''Muraenosaurus'' which was then described by H. G. Seeley.Seeley, HG. 1874. On ''Murænosaurus Leedsii'', a Plesiosaurian from the Oxford Clay. Part I. ''Quarterly Journal of the Geological Society'' 30: 197-208. The specimen may have suffered some damage due to the casual style of Charles Leeds’ collection. The first Muraenosaur was recovered with pieces missing from the skull and many of the caudal vertebrae absent. Because the animal was described from Charles Leeds’ collection it was given the name ''Muraeno ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Elasmosauridae
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 Streptos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pantosaurus
''Pantosaurus'' ("all lizard") is an extinct genus of plesiosaur from the Late Jurassic ( Oxfordian) of what is now Wyoming. It lived in what used to be the Sundance Sea. It was originally named ''Parasaurus'' ("near lizard") by Othniel Charles Marsh in reference to ''Plesiosaurus'', but that name was preoccupied, and Marsh changed it. The species ''Muraenosaurus reedii'' is in fact a junior synonym of ''Pantosaurus''. The holotype YPM 543 is a partial articulated skeleton, partially prepared to yield a distal humerus, four articulated carpals, a fragment of the coracoid, and several isolated cervical vertebrae from the Upper Member of the Sundance Formation. Other material includes USNM 536963, USNM 536965, UW 3, UW 5544 and UW 15938. Palaeobiology ''Pantosaurus'' possesses between 35 and 40 cervical vertebrae, which are very similar in proportion and morphology to those of '' Muraenosaurus leedsii'' from the Oxford Clay Formation (Callovian, Middle Jurassic) of England. The for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cryptoclididae
Cryptoclididae is a family (biology), family of medium-sized plesiosaurs that existed from the Middle Jurassic to the Early Cretaceous. They had long necks, broad and short skulls and densely packed teeth. They fed on small soft-bodied preys such as small fish and crustaceans. The earliest members of the family appeared during the early Bajocian, and they represented the dominant group of long-necked plesiosaurs during the latter half of the Jurassic. Classification In 2010, two supposed late Cretaceous members of the group were reclassified as other kinds of plesiosauroids. ''Kaiwhekea'' was reclassified to Leptocleididae, and ''Aristonectes'' was transferred to Elasmosauridae. Cladogram based on Ketchum and Benson (2010): References External links palaeos.com Cryptoclidids, Jurassic plesiosaurs Cretaceous plesiosaurs Callovian first appearances Late Cretaceous extinctions Prehistoric reptile families {{Jurassic-reptile-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cryptoclidid
Cryptoclididae is a family of medium-sized plesiosaurs that existed from the Middle Jurassic to the Early Cretaceous. They had long necks, broad and short skulls and densely packed teeth. They fed on small soft-bodied preys such as small fish and crustaceans. The earliest members of the family appeared during the early Bajocian, and they represented the dominant group of long-necked plesiosaurs during the latter half of the Jurassic. Classification In 2010, two supposed late Cretaceous members of the group were reclassified as other kinds of plesiosauroids. ''Kaiwhekea'' was reclassified to Leptocleididae, and ''Aristonectes'' was transferred to Elasmosauridae. Cladogram A cladogram (from Greek ''clados'' "branch" and ''gramma'' "character") is a diagram used in cladistics to show relations among organisms. A cladogram is not, however, an evolutionary tree because it does not show how ancestors are related to d ... based on Ketchum and Benson (2010): References External ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxford Clay
The Oxford Clay (or Oxford Clay Formation) is a Jurassic marine sedimentary rock formation underlying much of southeast England, from as far west as Dorset and as far north as Yorkshire. The Oxford Clay Formation dates to the Jurassic, specifically, the Callovian and Oxfordian ages, and comprises two main facies. The lower facies comprises the Peterborough Member, a fossiliferous organic-rich mudstone. This facies and its rocks are commonly known as lower Oxford Clay. The upper facies comprises the middle Oxford Clay, the Stewartby Member, and the upper Oxford Clay, the Weymouth Member. The upper facies is a fossil poor assemblage of calcareous mudstones. Oxford Clay appears at the surface around Oxford, Peterborough and Weymouth and is exposed in many quarries around these areas. The top of the Lower Oxford Clay shows a lithological change, where fissile shale changes to grey mudstone. The Middle and Upper Oxford Clays differ slightly, as they are separated by an argillaceou ... [...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 valid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1874 In Paleontology
Dinosaurs Publications *Richard Owen publishes a monograph on Wealden and Purbeck reptiles, classifying ''Scelidosaurus'', ''Iguanodon'' and ''Echinodon ''Echinodon'' is a genus of heterodontosaurid dinosaur that lived during the earliest Cretaceous of southern England and possibly western France in the Berriasian epoch. The first specimens were jaw bones named ''Echinodon becklesii'' by Sir Ric ...'' in the new dinosaur clade Prionodontia. Newly named dinosaurs Ichthyosaurs New taxa Plesiosaurs New taxa Pterosaurs Newly named pterosaurs Squamates Newly named mosasaurs References {{Reflist 1870s in paleontology Paleontology, 1874 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] |
Kimmerosaurus
''Kimmerosaurus'' ("lizard from Kimmeridge") is an extinct genus of plesiosaur from the family Cryptoclididae. ''Kimmerosaurus'' is most closely related to ''Tatenectes''. Discovery There are very few fossil remains of ''Kimmerosaurus'' known. In fact, nothing has been found to show what ''Kimmerosaurus'' may have looked like below the neck, although the atlas and the axis are similar to those of the plesiosaur ''Colymbosaurus''. It is this lack of any post-cranial fossils, and the bone similarities that has led to the belief that ''Kimmerosaurus'' fossils could be the missing head of ''Colymbosaurus'', a similar plesiosaur with no known skull fossils. The first part of the genus name of ''Kimmerosaurus'' comes from the location of the first ''Kimmerosaurus'' fossils, Kimmeridge Clay deposits of Dorset, England (these deposits are also the root word for the Kimmeridgian stage of the Jurassic period). The second part comes from the Greek word ('), "lizard". Description As ''K ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vertebrae
The spinal column, a defining synapomorphy shared by nearly all vertebrates,Hagfish are believed to have secondarily lost their spinal column is a moderately flexible series of vertebrae (singular vertebra), each constituting a characteristic irregular bone whose complex structure is composed primarily of bone, and secondarily of hyaline cartilage. They show variation in the proportion contributed by these two tissue types; such variations correlate on one hand with the cerebral/caudal rank (i.e., location within the vertebral column, backbone), and on the other with phylogenetic differences among the vertebrate taxon, taxa. The basic configuration of a vertebra varies, but the bone is its ''body'', with the central part of the body constituting the ''centrum''. The upper (closer to) and lower (further from), respectively, the cranium and its central nervous system surfaces of the vertebra body support attachment to the intervertebral discs. The posterior part of a vertebra fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
