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Neornithischia
Neornithischia ("new ornithischians") is a clade of the dinosaur order Ornithischia. It is the sister group of the Thyreophora within the clade Genasauria. Neornithischians are united by having a thicker layer of asymmetrical enamel on the inside of their lower teeth. The teeth wore unevenly with chewing and developed sharp ridges that allowed neornithischians to break down tougher plant food than other dinosaurs. Neornithischians include a variety of basal forms historically known as " hypsilophodonts", including the Parksosauridae; in addition, there are derived forms classified in the groups Marginocephalia and Ornithopoda. The former includes clades Pachycephalosauria and Ceratopsia, while the latter typically includes ''Hypsilophodon'' and the more derived Iguanodontia. Classification Neornithischia was first named by Cooper in 1985 and defined as "all genasaurians more closely related to '' Parasaurolophus walkeri'' than to ''Ankylosaurus magniventris'' or ''Stegosaurus s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thescelosauridae
Thescelosauridae is a clade of neornithischians from the Cretaceous of Asia, North America and possibly South America. The group was originally used as a name by Charles M. Sternberg in 1937, but was not formally defined until 2013, where it was used by Brown and colleagues as the group uniting ''Thescelosaurus'' and '' Orodromeus'', based on their phylogenetic results. During a phylogenetic revision of neornithischians by Clint Boyd in 2015, the authorship of Thescelosauridae was given to Brown and colleagues, which meant that the similar name Parksosauridae, informally defined in 2002 by Buchholz, would have had priority over Thescelosauridae. The two clades had slightly different definitions, with Parksosauridae referring to all animals closer to '' Parksosaurus'' than '' Hypsilophodon'', but they contained the same taxa so Boyd used Parksosauridae under the assumption it had priority. However, in formalizing the clade following the regulations of the PhyloCode, Madzia, Boyd, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jeholosauridae
Jeholosaurids were herbivorous neornithischian dinosaurs from the Cretaceous Period (Aptian - Cenomanian). The family was first proposed by Han ''et al.'' in 2012. The jeholosaurids were defined as all neornithischians more closely related to ''Jeholosaurus shangyuanensis'' than to ''Hypsilophodon foxii'', ''Iguanodon bernissartensis'', ''Protoceratops andrewsi'', '' Pachycephalosaurus wyomingensis'', or ''Thescelosaurus neglectus''. The Jeholosauridae includes the type genus ''Jeholosaurus'', and also possibly ''Yueosaurus'', ''Changchunsaurus'', and '' Haya''.Boyd CA. (2015) The systematic relationships and biogeographic history of ornithischian dinosaurs. PeerJ 3:e1523 https://doi.org/10.7717/peerj.1523 The cladogram below results from analysis by Herne ''et al.'', 2019, which added ''Changchunsaurus'' and '' Haya'' to Jeholosauridae, but moved ''Yueosaurus'' to the sister family Thescelosauridae Thescelosauridae is a clade of neornithischians from the Cretaceous of Asia, N ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Parksosauridae
Thescelosauridae is a clade of neornithischians from the Cretaceous of Asia, North America and possibly South America. The group was originally used as a name by Charles M. Sternberg in 1937, but was not formally defined until 2013, where it was used by Brown and colleagues as the group uniting ''Thescelosaurus'' and ''Orodromeus'', based on their phylogenetic results. During a phylogenetic revision of neornithischians by Clint Boyd in 2015, the authorship of Thescelosauridae was given to Brown and colleagues, which meant that the similar name Parksosauridae, informally defined in 2002 by Buchholz, would have had priority over Thescelosauridae. The two clades had slightly different definitions, with Parksosauridae referring to all animals closer to '' Parksosaurus'' than ''Hypsilophodon'', but they contained the same taxa so Boyd used Parksosauridae under the assumption it had priority. However, in formalizing the clade following the regulations of the PhyloCode, Madzia, Boyd ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sanxiasaurus
''Sanxiasaurus'' (meaning "Sanxia lizard", after the Three Gorges, Chinese ''Sanxia'', of the Yangtze River) is a genus of neornithischian dinosaur from the Middle Jurassic Xintiangou Formation in the Chongqing Municipality of China. The type and only species is ''S. modaoxiensis''. The holotype is a partial postcranial skeleton consisting of "55 bones including two cervical vertebrae, 11 dorsal vertebrae, 4 sacral vertebrae, 18 caudal vertebrae, both humeri, radii and ulnas, partial right ilium, partial right ischium, both femora and tibiae, left fibula, 3 metatarsi and 4 phalanges." In a phylogenetic analysis, it was found to be a basal neornithischian, more derived than ''Lesothosaurus'' and less derived than ''Hexinlusaurus ''Hexinlusaurus'' is a genus of basal ornithischian dinosaur from the Middle Jurassic of China. The holotype (ZDM T6001, Zigong Dinosaur Museum, Dashanpu, People's Republic of China), consists of an almost complete, articulated skull and some .... ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nanosaurus
''Nanosaurus'' ("small or dwarf lizard") is the name given to a genus of neornithischian dinosaur that lived about 155 to 148 million years ago, during the Late Jurassic-age. Its fossils are known from the Morrison Formation of the south-western United States. The type and only species, ''Nanosaurus agilis'', was described and named by Othniel Charles Marsh in 1877. The taxon has a complicated taxonomic history, largely the work of Marsh and Peter M. Galton, involving the genera ''Laosaurus'', ''Hallopus'', ''Drinker'', ''Othnielia'', and ''Othnielosaurus'', the latter three now being considered to be synonyms of ''Nanosaurus''. It had historically been classified as a hypsilophodont or fabrosaur, types of generalized small bipedal herbivore, but more recent research has abandoned these groupings as paraphyletic and ''Nanosaurus'' is today considered a basal member of Neornithischia. Description ''Nanosaurus'' is known from material from all parts of the body, including ... [...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, ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypsilophodont
Hypsilophodontidae (or Hypsilophodontia) is a traditionally used family of ornithopod dinosaurs, generally considered invalid today. It historically included many small bodied bipedal neornithischian taxa from around the world, and spanning from the Middle Jurassic until the Late Cretaceous. This inclusive status was supported by some phylogenetic analyses from the 1990s and mid 2000s, although there have also been many finding that the family is an unnatural grouping which should only include the type genus, ''Hypsilophodon'', with the other genera being within clades like Thescelosauridae and Elasmaria. A 2014 analysis by Norman recovered a grouping of ''Hypsilophodon'', Rhabdodontidae and ''Tenontosaurus'', which he referred to as Hypsilophodontia. All other analyses from around the same time have instead found these latter taxa to be within Iguanodontia. Linnaean usage Hypsilophodontidae was named originally in 1882 by Louis Dollo, as a family to include ''Hypsilophodon' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lesothosaurus
''Lesothosaurus'' is a Monotypic taxon, monospecific genus of ornithischian dinosaur that lived during the Early Jurassic in what is now South Africa and Lesotho. It was named by paleontologist Peter Galton in 1978, the name meaning "lizard from Lesotho". The genus has only one valid species, ''Lesothosaurus diagnosticus''. ''Lesothosaurus'' is one of the most completely-known early ornithischians, based on numerous skull and postcranial fossils from the Upper Elliot Formation. It had a simpler tooth and jaw anatomy than later ornithischians, and may have been omnivorous in some parts of the year. Discovery and naming Fossils referrable to ''Lesothosaurus'' may have been known from as early as 1959, when a right Mandible, dentary (lower jawbone) fragment bearing three teeth was collected by French geologist Jean Fabre from the Red beds, Red Beds of the Elliot Formation, Upper Elliot Formation near Mapheteng in Lesotho, Southern Africa, dating to the Early Jurassic (199(?)-190 mi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kulindadromeus
''Kulindadromeus'' was a herbivorous dinosaur, a basal neornithischian from the Middle Jurassic. The first ''Kulindadromeus'' fossil was found in Russia. Its feather-like integument is evidence for protofeathers being basal to Ornithischia and possibly Dinosauria as a whole, rather than just to Coelurosauria, as previously suspected. Discovery and naming In 2014, the type species ''Kulindadromeus zabaikalicus'' was named and described by Pascal Godefroit, Sofia Sinitsa, Danielle Dhouailly, Yuri Bolotsky, Alexander Sizov, Maria McNamara, Michael Benton, and Paul Spagna. The generic name is derived from the Kulinda sites and Classical Greek δρομεύς, ''dromeus'', "runner". The specific name refers to the Zabaykalsky Krai. The holotype, INREC K3/109, was found in a layer of the Ukureyskaya Formation dating from the Middle to Late Jurassic, Bajocian-Tithonian, with the specific bed likely dating to the Bathonian stage of the Middle Jurassic, between 168 and 166 million year ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Yandusaurus
''Yandusaurus'' is a genus of herbivorous basal neornithischian dinosaur from the Bathonian age (middle Jurassic, approximately 168 to 162 Ma) of China. Discovery and naming In January 1973 the Museum of the Salt Industry at Zigong in Sichuan was warned that during construction activities with a composter at Jinzidang near the Honghe dam inadvertently a dinosaur skeleton had been processed. A team of the museum managed to salvage some heavily damaged remains. Though locally this animal was at first referred to as "Yubasaurus" or "Honghesaurus", in 1979 Beijing professor He Xinlu named and described it as the type species ''Yandusaurus hongheensis''. The generic name is derived from ''Yandu'', the ancient name for Zigong. This name is a contraction of ''yan'', "salt", and ''du'', "capital", occasioned by the fact that Zigong was historically the centre of Chinese salt mining. In this way ''Yandusaurus'' indirectly also refers to the Salt Museum. The specific name refers to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hypsilophodon
''Hypsilophodon'' (; meaning "''Hypsilophus''-tooth") is a neornithischian dinosaur genus from the Early Cretaceous period of England. It has traditionally been considered an early member of the group Ornithopoda, but recent research has put this into question. The first remains of ''Hypsilophodon'' were found in 1849; the type species, ''Hypsilophodon foxii'', was named in 1869. Abundant fossil discoveries were made on the Isle of Wight, giving a good impression of the build of the species. It was a small, agile bipedal animal with an herbivorous or possibly omnivorous diet, measuring long and weighing . It had a pointed head equipped with a sharp beak used to bite off plant material, much like modern day parrots. Older studies have given rise to a number of misconceptions about ''Hypsilophodon'' that it was an armored, arboreal animal and that it could be found in areas outside of Wight. During the past decades, new researches have gradually shown this to be incorrect. Disco ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ornithopoda
Ornithopoda () is a clade of ornithischian dinosaurs, called ornithopods (), that started out as small, bipedal running grazers and grew in size and numbers until they became one of the most successful groups of herbivores in the Cretaceous world, dominating the North American land. Their major evolutionary advantage was the progressive development of a chewing apparatus that became the most sophisticated ever developed by a non-avian dinosaur, rivaling that of modern mammals such as the domestic cow. They reached their apex of diversity and ecological dominance in the hadrosaurids (colloquially known as 'duck-bills'), before they were wiped out by the Cretaceous–Paleogene extinction event along with all other non-avian dinosaurs. Members are known from all seven continents, though they are generally rare in the Southern Hemisphere. History of research In 1870, Thomas Henry Huxley listed Iguanodontidae (coined by Cope a year earlier) as one of his three families of dinosaur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
