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Piatnitzkysauridae
Piatnitzkysauridae is an extinct family of megalosauroid or basal allosauroid dinosaurs. It only consists of three to four known dinosaur genera: '' Condorraptor'', '' Marshosaurus'', '' Piatnitzkysaurus and'' possibly '' Xuanhanosaurus.'' 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 (however, if ''Xuanhanosaurus'' is included, this may expand their range). ''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 fi ... [...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 with respect to Allosauroidea, which is to say some members of this superfamily might be closer to Allosauroids than to each other, which is undesirable in cladistics. 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 c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Piatnitzkysaurus
''Piatnitzkysaurus'' ( ; meaning "Piatnitzky's lizard") is a genus of tetanuran 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 over 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., & LANGE ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Marshosaurus
''Marshosaurus'' is a genus of medium-sized carnivorous Theropoda, theropod dinosaur, belonging to the family Piatnitzkysauridae, from the Late Jurassic Morrison Formation of Utah and possibly Colorado. Discovery and naming During the 1960s, over fourteen thousand fossil bones were uncovered at the Cleveland-Lloyd Dinosaur Quarry, 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., James Henry Madsen Jr. as the genus ''Stokesosaurus''. In 1976 the second was by Madsen named as the type species ''Marshosaurus bicentesimus''. The generic name honoured the nineteenth century paleontologist Professor Othniel Charles Marsh, who described many dinosaur fossils during the Bone Wars. The Specific name (zoology), specific name was chosen "in honor of the bicentennial of the United States of America". The holotype, UMNH VP 6373, was found ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Allosauroid
Carnosauria is an extinct group of carnivorous theropod dinosaurs that lived during the Jurassic and Cretaceous periods. While Carnosauria was historically considered largely synonymous with Allosauroidea, some recent studies have revived Carnosauria as clade including both Allosauroidea and Megalosauroidea (which is sometimes recovered as paraphyletic with respect to Allosauroidea), and thus including the majority of non-coelurosaurian members of theropod clade Tetanurae. Other researchers have found Allosauroidea and Megalosauroidea to be unrelated groups.Cau A. (2024)A Unified Framework for Predatory Dinosaur Macroevolution Bollettino della Società Paleontologica Italiana, 63(1): 1-19. Distinctive characteristics of carnosaurs include large eye sockets, a long narrow skull and modifications of the legs and pelvis such as the thigh (femur) being longer than the shin (tibia). Carnosaurs first appeared in the Middle Jurassic around , and the last definitive carnosaur family ... [...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 th ... [...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 Geological period, period, between 243 and 233.23 million years ago (mya), although the exact origin and timing of the #Evolutionary history, evolution of dinosaurs is a subject of active research. They became the dominant terrestrial vertebrates after the Triassic–Jurassic extinction event 201.3 mya and their dominance continued throughout the Jurassic and Cretaceous periods. The fossil record shows that birds are feathered dinosaurs, Evolution of birds, having evolved from earlier Theropoda, 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 taxonomy (biology), taxonomic, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Xuanhanosaurus
''Xuanhanosaurus'' (meaning " Xuanhan lizard") is a genus of theropod dinosaur that lived during the Middle Jurassic (Bathonian) of the Sichuan Basin, China, around 166 million years ago. This taxon represents one of the various non- coelurosaurian tetanuran taxa found on the Middle Jurassic of the region, uncovered in the Lower Shaximiao Formation. Although it has been known for more than 40 years, this taxon has been the subject of very few studies, although most seem to agree that it is a tetanuran, possibly a basal allosauroid, highlighting the fact that it has a vestigial fourth metacarpal. Discovery The type species ''Xuanhanosaurus qilixiaensis'' was named by Dong Zhiming in 1984. The generic name refers to Xuanhan County in Sichuan, while the specific name is derived from the town of Qilixia. The specimen was recovered in 1979, when the author was conducting a Dinosaurian Fossil survey in Sichuan Province, when was guided by Liu Yawen and the 137th team to examine ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Allosauridae
Allosauridae is an extinct 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. 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 respectively. These crests would have been covered by keratin sheathes.Madsen, James H., Jr. (1993) 976 ''Allosaurus fragilis: A Revised Osteology''. Utah Geological Survey Bulletin 109 (2nd ed.). Salt La ... [...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 174.7 ±0.8 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 and Carbonif ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
United States
The United States of America (USA), also known as the United States (U.S.) or America, is a country primarily located in North America. It is a federal republic of 50 U.S. state, states and a federal capital district, Washington, D.C. The 48 contiguous states border Canada to the north and Mexico to the south, with the semi-exclave of Alaska in the northwest and the archipelago of Hawaii in the Pacific Ocean. The United States asserts sovereignty over five Territories of the United States, major island territories and United States Minor Outlying Islands, various uninhabited islands in Oceania and the Caribbean. It is a megadiverse country, with the world's List of countries and dependencies by area, third-largest land area and List of countries and dependencies by population, third-largest population, exceeding 340 million. Its three Metropolitan statistical areas by population, largest metropolitan areas are New York metropolitan area, New York, Greater Los Angeles, Los Angel ... [...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 154.8 ±0.8 Ma and 149.2 ±0.7 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, although it seems to have been first suggested by Thomas Webster in 1812. 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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
