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Thescelosaurine
Thescelosaurinae is a subfamily of thescelosaurid dinosaurs from the Early Cretaceous of Asia and the Late Cretaceous of North America. Distribution The distribution of Thescelosaurinae is quite large. They are widespread through United States and Canada where most of their fossils have been found. They also have a small group in North-Eastern China and Mongolia. Genera Studies disagree about which genera are included in the Thescelosaurinae. The group is defined to include ''Parksosaurus'' and '' Thescelosaurus'' and a cladistic analysis by C.M. Brown in 2013 concluded that the genera ''Changchunsaurus'', '' Haya'', ''Jeholosaurus'' and possibly ''Koreanosaurus'' are also thescelosaurines. Classification All thescelosaurines were originally included in the family Hypsilophodontidae, which is presently considered polyphyletic (unnatural). They are all now considered to be basal neornithischians, though more research is needed to be certain. They are the sister taxa to O ... [...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] |
Genus
Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus comes above species and below family (taxonomy), family. In binomial nomenclature, the genus name forms the first part of the binomial species name for each species within the genus. :E.g. ''Panthera leo'' (lion) and ''Panthera onca'' (jaguar) are two species within the genus ''Panthera''. ''Panthera'' is a genus within the family Felidae. The composition of a genus is determined by taxonomy (biology), taxonomists. The standards for genus classification are not strictly codified, so different authorities often produce different classifications for genera. There are some general practices used, however, including the idea that a newly defined genus should fulfill these three criteria to be descriptively useful: # monophyly – all descendants ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Haya Griva
''Haya'' is an extinct genus of basal neornithischian dinosaur known from Mongolia. Description ''Haya'' is known from several well-preserved specimens which collected in the Khugenetslavkant locality by the joint Mongolian Academy of Sciences from 2002 to 2007, from the Javkhlant Formation and a few from the Zos Canyon locality of the Gobi Desert. Both localities probably date to the Santonian-Campanian stages of the Late Cretaceous. The holotype IGM 100/2017 is composed of a complete and well preserved skull with some postcranial elements associated to it. Referred materials include IGM 100/1324, isolated left femur, IGM 100/2013, postcranial elements, IGM 100/2014, a crushed skull and postcranial elements, IGM 100/2015, a nearly complete postcranial skeleton, IGM 100/2016, a partial juvenile skull, IGM 100/2018, an isolated mandible with some teeth, IGM 100/2019, a nearly complete skull and skeleton and IGM 100/2020, postcranial fr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zephyrosaurus
''Zephyrosaurus'' (meaning "westward wind lizard") is a genus of orodromine ornithischian dinosaur. It is based on a partial skull and postcranial fragments discovered in the Aptian-Albian-age Lower Cretaceous Cloverly Formation of Carbon County, Montana, USA. New remains are under description, and tracks from Maryland and Virginia, also in the US, have been attributed to animals similar to ''Zephyrosaurus''. It lived approximately 113 mya. Discovery and history Hans-Dieter Sues named his new genus in recognition of the fossil being found in western North America, and Charles R. Schaff, who found the specimen. MCZ 4392, the type specimen, is composed of jaw fragments, the braincase and associated bones, several partial vertebrae, and rib fragments. He found the new genus to represent a previously unknown lineage of hypsilophodont (a taxon now considered not natural), similar in some respects to ''Hypsilophodon''. Because of the fragmentary nature of the type, and lack of ad ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orodromeus
''Orodromeus'' (meaning "Mountain Runner") is a genus of herbivorous orodromine thescelosaurid dinosaur from the Late Cretaceous of North America. Only one species is known, the type species ''Orodromeus makelai''. Discovery and naming The remains of ''Orodromeus'' were discovered by Robert Makela during the excavation in Teton County, Montana, of the ''Egg Mountain'' brooding colony of a much larger relative, ''Maiasaura''. The type species, ''Orodromeus makelai'', was named and shortly described by Jack Horner and David B. Weishampel in 1988. The generic name is derived from Greek ὄρος, ''oros'', "mountain", in reference to the Egg Mountain site, and δρομεύς, ''dromeus'', "runner", referring to the cursorial habits of the animal. The specific name honoured the late Makela.Horner, J. and Weishampel, D., 1988, "A comparative embryological study of two ornithischian dinosaurs", ''Nature'' (London), 332(No. 6161): 256-257 (1988) The holotype specimen, MOR 294, wa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Albertadromeus
''Albertadromeus'' is an extinct genus of orodromine thescelosaurid dinosaur known from the upper part of the Late Cretaceous Oldman Formation (middle Campanian stage) of Alberta, Canada. It contains a single species, ''Albertadromeus syntarsus''. Etymology The composite term ''Albertadromeus'' is derived from the name of the Canadian province "Alberta", and the Greek word ''dromeus'' (δρομεύς) meaning "runner", a reference to its inferred cursorial nature; thus "runner from Alberta". The specific name, ''syntarsus'' is derived from Greek words "syn" (συν) meaning "together" and "tarsus" (ταρσός) meaning "ankle", hence "together-ankle" a reference to the condition where its distal fibula is fused to its distal tibia. This dinosaur was described and named by Caleb Marshall Brown, David C. Evans, Michael J. Ryan & Anthony P. Russell in 2013 and the type species is ''Albertadromeus syntarsus''. Description The holotype specimen of ''Albertadromeus'' TMP 2009.037.00 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oryctodromeus
''Oryctodromeus'' (meaning "digging runner") was a genus of small orodromine thescelosaurid dinosaur. Fossils are known from the Late Cretaceous Blackleaf Formation of southwestern Montana and the Wayan Formation of southeastern Idaho, USA, both of the Cenomanian stage, roughly 95 million years ago. A member of the small, presumably fast-running herbivorous family Thescelosauridae, ''Oryctodromeus'' is the first non-avian dinosaur published that shows evidence of burrowing behavior. Description ''Oryctodromeus'' was originally described as lacking ossified tendons in the tail. However, specimens from the Wayan Formation demonstrate the presence of a thick tendon lattice in the dorsal, sacral, and caudal columns of some specimens; perhaps indicating more flexibility in ossified tendons than has previously been supposed.Krumenacker, L. J., 2010. Chronostratigraphy and paleontology of the mid-Cretaceous Wayan Formation of eastern Idaho, with a description of the first ''Oryctod ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orodrominae
Orodrominae is a subfamily of thescelosaurid dinosaurs known from the Cretaceous of North America and Asia. Distribution Orodromines were a mostly North American based group with fossils from Canada and United States only. ''Albertadromeus'', as its name suggests, is only from the upper (later) part of the Oldman Formation in the Belly River Group of Alberta, Canada. ''Orodromeus'', the type genus, was widespread through Montana. Its holotype was found at the Egg Mountain in the Two Medicine Formation. ''Oryctodromeus'' fossils were found in the Lima Peaks section of the Blackleaf Formation, also from Montana. ''Zephyrosaurus'', the most widespread genus, lived in southern Montana and northern Wyoming. The locality of its holotype is the Wolf Creek Canyon, which is a sandstone in the Cloverly Formation. Age Orodromines are widespread throughout time, starting in the Aptian and ending in the Campanian. The earliest fossils are of ''Zephyrosaurus'' and are from the Aptian (113 Ma ... [...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, and c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cladistics
Cladistics (; ) is an approach to biological classification in which organisms are categorized in groups (" clades") based on hypotheses of most recent common ancestry. The evidence for hypothesized relationships is typically shared derived characteristics ( synapomorphies'')'' that are not present in more distant groups and ancestors. However, from an empirical perspective, common ancestors are inferences based on a cladistic hypothesis of relationships of taxa whose character states can be observed. Theoretically, a last common ancestor and all its descendants constitute a (minimal) clade. Importantly, all descendants stay in their overarching ancestral clade. For example, if the terms ''worms'' or ''fishes'' were used within a ''strict'' cladistic framework, these terms would include humans. Many of these terms are normally used paraphyletically, outside of cladistics, e.g. as a 'grade', which are fruitless to precisely delineate, especially when including extinct species. R ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Koreanosaurus
''Koreanosaurus'' () is a genus of orodromine neornithischian dinosaur. One species has been described, ''Koreanosaurus boseongensis''. Discovery In 2003, three specimens of ''Koreanosaurus'' were found in the Late Cretaceous-age Seonso Conglomerate from the southern coast of the Bibong-ri dinosaur egg site, Boseong, Korean Peninsula. These specimens include the holotype KDRC-BB2, a partial upper skeleton lacking the skull, and two additional specimens which contains portions of the pelvic girdle and lower leg (KDRC-BB1 and KDRC-BB3). The type species was named after its locality (Boseong site 5). This taxon was initially named and described in a master's thesis by Dae-Gil Lee in 2008, and was officially published by Min Huh, Dae-Gil Lee, Jung-Kyun Kim, Jong-Deock Lim and Pascal Godefroit in 2011. Description ''Koreanosaurus'' was a relatively small dinosaur, reaching in body length. Based on its taxonomic position and the existence of small burrows from the Seonso Conglome ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jeholosaurus
''Jeholosaurus'' is a genus of neornithischian dinosaur from the Early Cretaceous Period. It is thought to have been a herbivorous small ornithopod. History of discovery The first two ''Jeholosaurus'' specimens were found in 2000 at Lujiatun near Beipiao City, Liaoning Province, China, and named and described the same year by Xu Xing, Wang Xioalin and You Hailu. The type and only known species is ''Jeholosaurus shangyuanensis''. The generic name ''Jeholosaurus'' means "lizard from Jehol"; Jehol is the name of a historical province situated in western Liaoning and northern Hebei. The specific name refers to the geographical area of Shangyuan where the fossil site is located. The type specimen of ''Jeholosaurus'', on which the genus is based, is IVPP V 12529. It was found in a layer of the early Yixian Formation, dating from the early Aptian, about 126-125 million years old. The layers consist of fluvial sandstone interspersed with tuff and it is thought that an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
