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Piatnitzkysauridae
Piatnitzkysauridae is an extinct family of megalosauroid or basal Allosauroid dinosaurs. It only consists of three known dinosaur genera: '' Condorraptor'', ''Marshosaurus'', and ''Piatnitzkysaurus.'' The most complete and well known member of this family is ''Piatnitzkysaurus'', which also gives the family its name. Description So far all known piatnitzkysaurids have only been found in Jurassic deposits of the western hemisphere/New world. ''Piatnitzkysaurus'' and ''Condorraptor'' hail from the Cañadón Asfalto Formation of Argentina, which has been dated from the Toarcian epoch of the Early Jurassic to the Bathonian epoch of the Middle Jurassic (approximately 179 to 168 million years ago). ''Marshosaurus'' was found in the Morrison Formation of the United States, which was dated to the Kimmeridgian epoch of the Late Jurassic. Piatnitzkysaurids were among the first large theropods present in South America, and are evidence for a radiation of basal tetanurans in the middle Jur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Megalosauroidea
Megalosauroidea (meaning 'great/big lizard forms') is a superfamily (or clade) of tetanuran theropod dinosaurs that lived from the Middle Jurassic to the Late Cretaceous period. The group is defined as ''Megalosaurus bucklandii'' and all taxa sharing a more recent common ancestor with it than with ''Allosaurus fragilis'' or ''Passer domesticus''. Members of the group include ''Spinosaurus'', ''Megalosaurus'', and ''Torvosaurus''. They are possibly paraphyletic in nature. Classification The name Spinosauroidea is sometimes used in place of Megalosauroidea. The superfamily Spinosauroidea was named in 1915 by Ernst Stromer. It is a synonym of Megalosauroidea in almost all modern phylogenetic analyses, and it is therefore redundant. Spinosauroidea was defined as a clade in 1998 by Paul Sereno as the node clade containing the common ancestor of ''Spinosaurus'' and ''Torvosaurus'' and all its descendants. Thomas Holtz in 2004 defined a branch clade with the same name containing all spec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Allosauroid
Allosauroidea is a superfamily or clade of theropod dinosaurs which contains four families — the Metriacanthosauridae, Allosauridae, Carcharodontosauridae, and Neovenatoridae. Allosauroids, alongside the family Megalosauroidea, were among the apex predators that were active during the Middle Jurassic to Late Cretaceous periods. The most famous and best understood allosauroid is the North American genus ''Allosaurus''. The oldest-known allosauroid, '' Shidaisaurus jinae'', appeared in the early Middle Jurassic about 174 million years ago (Earliest Aalenian stage) of China. The last known definitive surviving members of the group died out around 89 million years ago in Asia (''Shaochilong'') and South America (''Mapusaurus''), though the megaraptorans, which survived until the end of Maastrichtian, may belong to the group as well. A frontal assigned to an allosauroid found to be most closely related to ''Sinraptor'' has also been found in the Coniacian (89-86.3 Ma) of Argen ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Piatnitzkysaurus
''Piatnitzkysaurus'' ( meaning "Piatnitzky's lizard") is a genus of megalosauroid theropod dinosaur that lived approximately 179 to 177 million years ago during the lower part of the Jurassic Period in what is now Argentina. ''Piatnitzkysaurus'' was a moderately large, lightly built, bipedal, ground-dwelling carnivore that could grow up to long. Discovery and naming The holotype specimen of ''Piatnitzkysaurus'', PVL 4073, was collected during expeditions in 1977, 1982, and 1983 at the Cañadón Asfalto Formation in sediments that were deposited during the Middle-Late Toarcian stage of the Jurassic period, approximately 179 to 177 million years ago.Bonaparte, J. F. (1979)Dinosaurs: a Jurassic assemblage from Patagonia.''Science'', ''205''(4413), 1377-1379. The specimen was very complete and is one of the best known from a Megalosaur, including a partial skull and partial anterior postcranial skeleton of a subadult individual preserved in semi-articulation.Bonaparte, J. F., & L ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Piatnitzkysaurus Floresi
''Piatnitzkysaurus'' ( meaning "Piatnitzky's lizard") is a genus of megalosauroid theropod dinosaur that lived approximately 179 to 177 million years ago during the lower part of the Jurassic Period in what is now Argentina. ''Piatnitzkysaurus'' was a moderately large, lightly built, bipedal, ground-dwelling carnivore that could grow up to long. Discovery and naming The holotype specimen of ''Piatnitzkysaurus'', PVL 4073, was collected during expeditions in 1977, 1982, and 1983 at the Cañadón Asfalto Formation in sediments that were deposited during the Middle-Late Toarcian stage of the Jurassic period, approximately 179 to 177 million years ago.Bonaparte, J. F. (1979)Dinosaurs: a Jurassic assemblage from Patagonia.''Science'', ''205''(4413), 1377-1379. The specimen was very complete and is one of the best known from a Megalosaur, including a partial skull and partial anterior postcranial skeleton of a subadult individual preserved in semi-articulation.Bonaparte, J. F., & L ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Condorraptor
''Condorraptor'' is an extinct genus of megalosauroid theropod dinosaur. Its genus name means 'robber from Cerro Condor', referencing a nearby village, while its species name, ''currumili'', is named after Hipolito Currumil, the landowner and discoverer of the locality. It was among the earliest large South American theropods, having been found in Lower Jurassic strata of the Cañadón Asfalto Formation in the Cañadón Asfalto Basin of Argentina. The type species, described in 2005, is ''Condorraptor currumili''. It is based on a tibia, with an associated partial skeleton that may belong to the same individual. Initially described as a basal tetanuran, Benson (2010) found it to be a piatnitzkysaurid megalosauroid and the sister taxon of ''Piatnitzkysaurus,'' a finding supported by later studies. Description The holotype of ''Condorraptor'' is MPEF-PV 1672, a left tibia. Additional remains (MPEF-PV 1673 through 1697 and MPEF-PV 1700 through 1705) have also been referred to t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Marshosaurus
''Marshosaurus'' is a genus of medium-sized carnivorous theropod dinosaur, belonging to the Megalosauroidea, from the Late Jurassic Morrison Formation of Utah and possibly Colorado. Description ''Marshosaurus'' was medium-sized for a theropod. In 2010, Gregory S. Paul estimated its length at and its weight at . The holotype ilium has a length of . If the cranial material is correctly referred, the skull was about long. In 2012, Matthew Carrano established one autapomorphy, a unique derived trait of the holotype: the suture between the pubic peduncle and the pubic bone is convex, curving upwards, at the front and concave at the rear. Discovery and naming During the 1960s, over fourteen thousand fossil bones were uncovered at the Cleveland-Lloyd Quarry in central Utah. The majority of these belonged to ''Allosaurus'' but some were of at least two theropods new to science. In 1974 one of these was named by James Henry Madsen Jr. as the genus ''Stokesosaurus''. In 1976 the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Allosauridae
Allosauridae is a family of medium to large bipedal, carnivorous allosauroid theropod dinosaurs from the Late Jurassic. Allosauridae is a fairly old taxonomic group, having been first named by the American paleontologist Othniel Charles Marsh in 1878. Allosaurids are characterized by an astragalus with a restriction of the ascending process to the lateral part of the bone, a larger medial than lateral condyle, and a horizontal groove across the face of the condyles. Description Allosaurids have a general anatomy typical of other neotheropod dinosaurs, contributing to the difficulty in defining the family's membership. A typical 8m specimen of ''Allosaurus fragilis'' had a skull of about 0.85m. The premaxilla has five teeth and the maxilla usually around 16. The dentary also typically has 16 teeth. All teeth are serrated and continuously replaced throughout the life of the animal. Allosaurid skulls are characterized by two sets of crests formed by the nasal and lacrimal bones res ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dinosaur
Dinosaurs are a diverse group of reptiles of the clade Dinosauria. They first appeared during the Triassic period, between 243 and 233.23 million years ago (mya), although the exact origin and timing of the evolution of dinosaurs is the subject of active research. They became the dominant terrestrial vertebrates after the Triassic–Jurassic extinction event 201.3 mya; their dominance continued throughout the Jurassic and Cretaceous periods. The fossil record shows that birds are feathered dinosaurs, having evolved from earlier theropods during the Late Jurassic epoch, and are the only dinosaur lineage known to have survived the Cretaceous–Paleogene extinction event approximately 66 mya. Dinosaurs can therefore be divided into avian dinosaurs—birds—and the extinct non-avian dinosaurs, which are all dinosaurs other than birds. Dinosaurs are varied from taxonomic, morphological and ecological standpoints. Birds, at over 10,700 living species, are among ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Early Jurassic
The Early Jurassic Epoch (geology), Epoch (in chronostratigraphy corresponding to the Lower Jurassic series (stratigraphy), Series) is the earliest of three epochs of the Jurassic Period. The Early Jurassic starts immediately after the Triassic-Jurassic extinction event, 201.3 Ma (million years ago), and ends at the start of the Middle Jurassic 174.1 Ma. Certain rocks of marine origin of this age in Europe are called "Lias Group, Lias" and that name was used for the period, as well, in 19th-century geology. In southern Germany rocks of this age are called Black Jurassic. Origin of the name Lias There are two possible origins for the name Lias: the first reason is it was taken by a geologist from an England, English quarryman's dialect pronunciation of the word "layers"; secondly, sloops from north Cornwall, Cornish ports such as Bude would sail across the Bristol Channel to the Vale of Glamorgan to load up with rock from coastal limestone quarries (lias limestone from S ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Morrison Formation
The Morrison Formation is a distinctive sequence of Late Jurassic, Upper Jurassic sedimentary rock found in the western United States which has been the most fertile source of dinosaur fossils in North America. It is composed of mudstone, sandstone, siltstone, and limestone and is light gray, greenish gray, or red. Most of the fossils occur in the green siltstone beds and lower sandstones, relics of the rivers and floodplains of the Jurassic period. It is centered in Wyoming and Colorado, with outcrops in Montana, North Dakota, South Dakota, Nebraska, Kansas, the panhandles of Oklahoma and Texas, New Mexico, Arizona, Utah, and Idaho. Equivalent rocks under different names are found in Canada. It covers an area of 1.5 million square kilometers (600,000 square miles), although only a tiny fraction is exposed and accessible to geologists and Paleontology, paleontologists. Over 75% is still buried under the prairie to the east, and much of its western paleogeographic extent ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States
The United States of America (U.S.A. or USA), commonly known as the United States (U.S. or US) or America, is a country primarily located in North America. It consists of 50 states, a federal district, five major unincorporated territories, nine Minor Outlying Islands, and 326 Indian reservations. The United States is also in free association with three Pacific Island sovereign states: the Federated States of Micronesia, the Marshall Islands, and the Republic of Palau. It is the world's third-largest country by both land and total area. It shares land borders with Canada to its north and with Mexico to its south and has maritime borders with the Bahamas, Cuba, Russia, and other nations. With a population of over 333 million, it is the most populous country in the Americas and the third most populous in the world. The national capital of the United States is Washington, D.C. and its most populous city and principal financial center is New York City. Paleo-Americ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kimmeridgian
In the geologic timescale, the Kimmeridgian is an age in the Late Jurassic Epoch and a stage in the Upper Jurassic Series. It spans the time between 157.3 ± 1.0 Ma and 152.1 ± 0.9 Ma (million years ago). The Kimmeridgian follows the Oxfordian and precedes the Tithonian. Stratigraphic definition The Kimmeridgian Stage takes its name from the village of Kimmeridge on the Dorset coast, England. The name was introduced into the literature by French geologist Alcide d'Orbigny in 1842. The Kimmeridge Clay Formation takes its name from the same type location (although this formation extends from the Kimmeridgian stage of the Upper Jurassic into the Lower Cretaceous). It is the source for about 95% of the petroleum in the North Sea. Historically, the term Kimmeridgian has been used in two different ways. The base of the interval is the same but the top was defined by British stratigraphers as the base of the Portlandian (''sensu anglico'') whereas in France the top was defined as t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
