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Caenagnathoidea
Caenagnathoidea ("recent jaw forms") is a group of advanced oviraptorosaurian dinosaurs from the Cretaceous Period (geology), Period of what are now Asia and North America. They are distinct for their characteristically short, beaked, parrot-like skulls, often with bony crests atop the head. They ranged in size from ''Caudipteryx'', which was the size of a turkey, to the 8 meter long, 1.4 ton ''Gigantoraptor''.Xu, X., Tan, Q., Wang, J., Zhao, X., and Tan, L. (2007). "A gigantic bird-like dinosaur from the Late Cretaceous of China." ''Nature'', 447: 844-847. The group (along with all maniraptoran dinosaurs) is close to the ancestry of birds. The most complete specimens have been found in Asia, representing members of the sub-group Oviraptorinae. Notable but fragmentary remains are also known from North America, almost all of which belong to the subgroup Elmisaurinae.Varricchio, D. J. 2001. Late Cretaceous oviraptorosaur (Theropoda) dinosaurs from Montana. pp. 42–57 in D. H. Tanke ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oviraptorosauria
Oviraptorosaurs ("egg thief lizards") are a group of feathered maniraptoran dinosaurs from the Cretaceous Period of what are now Asia and North America. They are distinct for their characteristically short, beaked, parrot-like skulls, with or without bony crests atop the head. They ranged in size from ''Caudipteryx'', which was the size of a turkey, to the 8-meter-long, 1.4-ton ''Gigantoraptor''. The group (along with all maniraptoran dinosaurs) is close to the ancestry of birds. Some researchers such as Maryanska ''et al'' (2002) and Osmólska ''et al.'' (2004) have proposed that they may represent primitive flightless birds.Osmólska, Halszka, Currie, Philip J., Brasbold, Rinchen (2004) "The Dinosauria" Weishampel, Dodson, Osmólska. "Chapter 8 Oviraptorosauria" University of California Press. The most complete oviraptorosaur specimens have been found in Asia. The North American oviraptorosaur record is sparse.Varricchio, D. J. 2001. Late Cretaceous oviraptorosaur (Theropoda) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Caenagnathus Collinsi
''Caenagnathus'' ('recent jaw') is a genus of caenagnathid oviraptorosaurian dinosaur from the late Cretaceous period (Campanian stage; ~75 million years ago). It is known from partial remains including lower jaws, a tail vertebra, hand bones, and hind limbs, all found in the Dinosaur Park Formation of Alberta, Canada. ''Caenagnathus'' measured about long and weighed about . Description ''Caenagnathus'' was a large oviraptorosaurian, with some specimens suggesting it achieved sizes comparable to its relative ''Anzu''. Like ''Anzu'', it had a toothless lower beak that was shallower in depth than those of elmisaurines. It also shared with ''Anzu'' less gracile proportions than those of elmisaurines. Like all oviraptorosaurs, it would most likely have possessed a coat of feathers. Classification This dinosaur has a confusing history. In 1936, a set of jaws (CMN 8776) were found, and later given the name ''Caenagnathus'', meaning 'recent jaw'; they were first thought to be tho ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Caenagnathus
''Caenagnathus'' ('recent jaw') is a genus of caenagnathid oviraptorosaurian dinosaur from the late Cretaceous period (Campanian stage; ~75 million years ago). It is known from partial remains including lower jaws, a tail vertebra, hand bones, and hind limbs, all found in the Dinosaur Park Formation of Alberta, Canada. ''Caenagnathus'' measured about long and weighed about . Description ''Caenagnathus'' was a large oviraptorosaurian, with some specimens suggesting it achieved sizes comparable to its relative ''Anzu''. Like ''Anzu'', it had a toothless lower beak that was shallower in depth than those of elmisaurines. It also shared with ''Anzu'' less gracile proportions than those of elmisaurines. Like all oviraptorosaurs, it would most likely have possessed a coat of feathers. Classification This dinosaur has a confusing history. In 1936, a set of jaws (CMN 8776) were found, and later given the name ''Caenagnathus'', meaning 'recent jaw'; they were first thought to be tho ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Elmisaurinae
Caenagnathidae is a family of bird-like maniraptoran theropod dinosaurs from the Cretaceous of North America and Asia. They are a member of the Oviraptorosauria, and close relatives of the Oviraptoridae. Like other oviraptorosaurs, caenagnathids had specialized beaks, long necks, and short tails, and would have been covered in feathers. The relationships of caenagnathids were long a puzzle. The family was originally named by Raymond Martin Sternberg in 1940 as a family of flightless birds. The discovery of skeletons of the related oviraptorids revealed that they were in fact non-avian theropods, and the discovery of more complete caenagnathid remains revealed that ''Chirostenotes pergracilis'', originally named on the basis of a pair of hands, and ''Citipes elegans'', originally thought to be an ornithomimid, named from a foot, were caenagnathids as well. Anatomy Overall, the anatomy of the caenagnathids is similar to that of the closely related Oviraptoridae, but there are a n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oviraptorinae
Oviraptoridae is a group of bird-like, herbivorous and omnivorous maniraptoran dinosaurs. Oviraptorids are characterized by their toothless, parrot-like beaks and, in some cases, elaborate crests. They were generally small, measuring between one and two metres long in most cases, though some possible oviraptorids were enormous. Oviraptorids are currently known only from the Late Cretaceous of Asia, with the most well-known species and complete specimens found only in the Gobi Desert of Mongolia and northwestern China. Description The most characteristic feature of this group is the skull structure. Oviraptorids had short snouts and very deep mandibles. Some taxa (such as ''Citipati'', ''Corythoraptor'', ''Rinchenia'') had a midline crest on top of the skull, resembling that of a cassowary. Other distinguishing characteristics include a bony spike intruding on the mandibular fenestra, nostrils placed very high and far back on the snout, an extremely thin bony bar beneath the eye, ... [...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] |
Oviraptoridae
Oviraptoridae is a group of bird-like, herbivorous and omnivorous maniraptoran dinosaurs. Oviraptorids are characterized by their toothless, parrot-like beaks and, in some cases, elaborate crests. They were generally small, measuring between one and two metres long in most cases, though some possible oviraptorids were enormous. Oviraptorids are currently known only from the Late Cretaceous of Asia, with the most well-known species and complete specimens found only in the Gobi Desert of Mongolia and northwestern China. Description The most characteristic feature of this group is the skull structure. Oviraptorids had short snouts and very deep mandibles. Some taxa (such as ''Citipati'', ''Corythoraptor'', ''Rinchenia'') had a midline crest on top of the skull, resembling that of a cassowary. Other distinguishing characteristics include a bony spike intruding on the mandibular fenestra, nostrils placed very high and far back on the snout, an extremely thin bony bar beneath the eye, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Caenagnathidae
Caenagnathidae is a family of bird-like maniraptoran theropod dinosaurs from the Cretaceous of North America and Asia. They are a member of the Oviraptorosauria, and close relatives of the Oviraptoridae. Like other oviraptorosaurs, caenagnathids had specialized beaks, long necks, and short tails, and would have been covered in feathers. The relationships of caenagnathids were long a puzzle. The family was originally named by Raymond Martin Sternberg in 1940 as a family of flightless birds. The discovery of skeletons of the related oviraptorids revealed that they were in fact non-avian theropods, and the discovery of more complete caenagnathid remains revealed that ''Chirostenotes pergracilis'', originally named on the basis of a pair of hands, and ''Citipes elegans'', originally thought to be an ornithomimid, named from a foot, were caenagnathids as well. Anatomy Overall, the anatomy of the caenagnathids is similar to that of the closely related Oviraptoridae, but there are a n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Avimimus
''Avimimus'' ( ), meaning "bird mimic" (Latin ''avis'' = bird + ''mimus'' = mimic), is a genus of oviraptorosaurian theropod dinosaur, named for its bird-like characteristics, that lived in the late Cretaceous in what is now Mongolia, around 85 to 70 million years ago. Description ''Avimimus'' was a small, bird-like dinosaur with a length of 1.5 m (5 ft). The skull was small compared to the body, though the brain and eyes were large. The size of the bones which surrounded the brain and were dedicated to protecting it are large. This is also consistent with the hypothesis that ''Avimimus'' had a proportionally large brain. The jaws of ''Avimimus'' were thought to form a parrot-like beak lacking teeth, and a thorough review of the holotype specimen's anatomy confirmed that no teeth were preserved, although a series of tooth-like projections along the tip of the premaxilla were. However, subsequently discovered specimens have been reported to preserve small prem ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chirostenotes
''Chirostenotes'' ( ; named from Greek 'narrow-handed') is a genus of oviraptorosaurian dinosaur from the late Cretaceous (about 76.5 million years ago) of Alberta, Canada. The type species is ''Chirostenotes pergracilis''. History of discovery ''Chirostenotes'' has a confusing history of discovery and naming. The first fossils of ''Chirostenotes'', a pair of hands, were in 1914 found by George Fryer Sternberg near Little Sandhill Creek in the Campanian Dinosaur Park Formation of Canada, which has yielded the most dinosaurs of any Canadian formation. The specimens were studied by Lawrence Morris Lambe who, however, died before being able to formally name them. In 1924, Charles Whitney Gilmore adopted the name he found in Lambe's notes and described and named the type species ''Chirostenotes pergracilis''. The generic name is derived from Greek ''cheir'', "hand", and ''stenotes'', "narrowness". The specific name means "throughout", ''per~'', "gracile", ''gracilis'', in Latin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Yixian Formation
The Yixian Formation (; formerly transcribed as Yihsien Formation) is a geological formation in Jinzhou, Liaoning, People's Republic of China, that spans the late Barremian and early Aptian stages of the Early Cretaceous. It is known for its exquisitely preserved fossils, and is mainly composed of basalts interspersed with siliciclastic sediments. History Japanese occupation The potential importance of the Yixian Formation was initially recognized during the time the Empire of Japan occupied China's Rehe ("Jehol") Province after the First battle of Hopei in 1933. Many Japanese scientists had noticed fossil remains of extinct fish and reptiles, possibly the champsosaurs. These initial fossil discoveries made by Japanese scientists vanished once World War II ended in 1945. Chinese rediscovery By 1949, when administration of the area passed to the Chinese Communist Party and its leader Mao Zedong, the fossils of Yixian were studied only by Chinese scientists. It was not unt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rinchenia
''Rinchenia'' (named after Byambyn Rinchen) is a genus of oviraptorid dinosaur that lived in Asia during the Late Cretaceous epoch in what is now Mongolia, Nemegt Formation, around 70 million years ago. The type and only known species, ''Rinchenia mongoliensis'', was originally classified as a species within the genus ''Oviraptor'' (named ''Oviraptor mongoliensis''), but a subsequent rexamination found differences significant enough to warrant a separate genus. The name ''Rinchenia'' was coined for this new genus, though not formally described in detail. History of discovery During 1984, a nearly complete oviraptorid skeleton was discovered at the Altan Uul II (or Altan Ula II) locality of the highly fossiliferous Nemegt Formation, Gobi Desert. This newly collected specimen, MPC-D 100/32-A, included the skull and lower jaws in their entirety, nearly complete vertebral column, forelimbs with shoulder girdle, and partial hindlimbs with pelvic girdle. Later on, Mongolian paleontol ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
