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Caenagnathoid
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] |
Gigantoraptor
''Gigantoraptor'' () is a genus of large oviraptorosaur dinosaur that lived in Asia during the Late Cretaceous period. It is known from the Iren Dabasu Formation of Inner Mongolia, where the first remains were found in 2005. ''Gigantoraptor'' was the largest oviraptorosaur, reaching in length and in body mass. It had an extensively pneumatized vertebral column and elongated arms and legs. Both femur and tibia measured over in length, an unusual trait among giant theropods. The lower jaws were toothless and ended in a keratinous beak, as seen in other oviraptorosaurs. Though several oviraptorosaur species are known to have developed a full coat of feathers, ''Gigantoraptor'', due to its size, could have lost some of this integument. The genus is classified as an oviraptorosaurian dinosaur, a group of generally small feathered animals. Though it was originally found to represent a basal oviraptorid, subsequent analyses have shown it to be a caenagnathid. It was a giant, ground ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cretaceous
The Cretaceous ( ) is a geological period that lasted from about 145 to 66 million years ago (Mya). It is the third and final period of the Mesozoic Era, as well as the longest. At around 79 million years, it is the longest geological period of the entire Phanerozoic. The name is derived from the Latin ''creta'', "chalk", which is abundant in the latter half of the period. It is usually abbreviated K, for its German translation ''Kreide''. The Cretaceous was a period with a relatively warm climate, resulting in high eustatic sea levels that created numerous shallow inland seas. These oceans and seas were populated with now- extinct marine reptiles, ammonites, and rudists, while dinosaurs continued to dominate on land. The world was ice free, and forests extended to the poles. During this time, new groups of mammals and birds appeared. During the Early Cretaceous, flowering plants appeared and began to rapidly diversify, becoming the dominant group of plants across the Earth b ... [...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] |
Elmisaurus
''Elmisaurus'' (meaning "foot sole lizard") is an extinct genus of caenagnathid dinosaur from the Late Cretaceous Nemegt Formation of Mongolia. It was a theropod belonging to the Oviraptorosauria. Discovery In 1970, a paleontological Polish-Mongolian expedition discovered two fragmentary specimens of a small theropod in the Ömnögovĭ province of Mongolia. The type species, ''Elmisaurus rarus'', was named and described by Halszka Osmólska in 1981. The generic name is derived from Mongol ' or ', "foot sole", as the type specimen consisted of a metatarsus. The specific name means "rare" in Latin. The holotype, ZPAL MgD-I/172, consists of a left metatarsus fused with the tarsalia. There are two paratypes: ZPAL MgD-I/98, consisting of a right hand and foot, and ZPAL MgD-I/20, the upper part of the left metatarsus of a larger individual.Osmólska, H. (1981). Coossified tarsometatarsi in theropod dinosaurs and their bearing on the problem of bird origins. ''Palaeontologica Polon ... [...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] |
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] |
Citipati (dinosaur)
''Citipati'' (; meaning "funeral pyre lord") is a genus of oviraptorid dinosaur that lived in Asia during the Late Cretaceous period, about 75 million to 71 million years ago. It is mainly known from the Ukhaa Tolgod locality at the Djadokhta Formation, where the first remains were collected during the 1990s. The genus and type species ''Citipati osmolskae'' were named and described in 2001. A second species from the adjacent Zamyn Khondt locality may also exist. ''Citipati'' is one of the best-known oviraptorids thanks to a number of well-preserved specimens, including individuals found in brooding positions atop nests of eggs, though most of them were initially referred to the related ''Oviraptor''. These nesting specimens have helped to solidify the link between non-avian dinosaurs and birds. ''Citipati'' was among the largest oviraptorids; it is estimated to have been around in length and to have weighed . Its skull was highly pneumatized, short, and had a characteristic c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oviraptor
''Oviraptor'' (; ) is a genus of oviraptorid dinosaur that lived in Asia during the Late Cretaceous period. The first remains were collected from the Djadokhta Formation of Mongolia in 1923 during a paleontological expedition led by Roy Chapman Andrews, and in the following year the genus and type species ''Oviraptor philoceratops'' were named by Henry Fairfield Osborn. The genus name refers to the initial thought of egg-stealing habits, and the specific name was intended to reinforce this view indicating a preference over ceratopsian eggs. Despite the fact that numerous specimens have been referred to the genus, ''Oviraptor'' is only known from a single partial skeleton regarded as the holotype, as well as a nest of about fifteen eggs and several small fragments from a juvenile. ''Oviraptor'' was a rather small feathered oviraptorid, estimated at long with a weight between . It had a wide lower jaw with a skull that likely had a crest. Both upper and lower jaws were toothless ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microvenator
''Microvenator'' (meaning "small hunter") is a genus of dinosaur from the Early Cretaceous Cloverly Formation in what is now south central Montana. ''Microvenator'' was an oviraptorosaurian theropod. The holotype fossil is an incomplete skeleton, most likely a juvenile with a length of , and consequently, the adult size remains uncertain. ''Microvenator celer'' is primitive and may be the "sister taxon to all other oviraptorosaurs."Varricchio, D. J. 2001. Late Cretaceous oviraptorosaur (Theropoda) dinosaurs from Montana. pp. 42–57 in D. H. Tanke and K. Carpenter (eds.), Mesozoic Vertebrate Life. Indiana University Press, Indianapolis, Indiana. Discovery Barnum Brown collected the type specimen (AMNH 3041) in 1933 by a field party working for the American Museum of Natural History and he erroneously included ''Deinonychus'' teeth with the specimen. Because of this, Brown informally dubbed it "Megadontosaurus" ("big-toothed lizard"), Brown made illustrations of it, but ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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 descendants, nor does it show how much they have changed, so many differing evolutionary trees can be consistent with the same cladogram. A cladogram uses lines that branch off in different directions ending at a clade, a group of organisms with a last common ancestor. There are many shapes of cladograms but they all have lines that branch off from other lines. The lines can be traced back to where they branch off. These branching off points represent a hypothetical ancestor (not an actual entity) which can be inferred to exhibit the traits shared among the terminal taxa above it. This hypothetical ancestor might then provide clues about the order of evolution of various features, adaptation, and other evolutionary narratives about ance ... [...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] |
China
China, officially the People's Republic of China (PRC), is a country in East Asia. It is the world's most populous country, with a population exceeding 1.4 billion, slightly ahead of India. China spans the equivalent of five time zones and borders fourteen countries by land, the most of any country in the world, tied with Russia. Covering an area of approximately , it is the world's third largest country by total land area. The country consists of 22 provinces, five autonomous regions, four municipalities, and two Special Administrative Regions (Hong Kong and Macau). The national capital is Beijing, and the most populous city and financial center is Shanghai. Modern Chinese trace their origins to a cradle of civilization in the fertile basin of the Yellow River in the North China Plain. The semi-legendary Xia dynasty in the 21st century BCE and the well-attested Shang and Zhou dynasties developed a bureaucratic political system to serve hereditary monarchies, or dyna ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
