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Crosbysaurus
''Crosbysaurus'' is a genus of extinct archosauromorph that lived in the Late Triassic of Arizona, New Mexico, North Carolina, Texas, and Utah. It is known from the Chinle Formation and Dockum Group rock units from the southwestern United States. The type species is ''C. harrisae'', and the only known material includes teeth. 11 specimens are known, each including a single tooth. ''Crosbysaurus'' was originally identified as an ornithischian dinosaur by Andrew Heckert when it was first described in 2004. Further work has shown that it is likely an archosauromorph based on the features of its teeth, and it may belong to Archosauriformes. The taxon is likely valid as it differs from other genera from the same region known from teeth like '' Revueltosaurus'', '' Tecovasaurus'', ''Krzyzanowskisaurus'', ''Lucianosaurus'', and '' Protecovasaurus''. Description The teeth of ''Crosbysaurus'' are triangular in outline with serrations Serration is a saw-like appearance or a row ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crosbysaurus Hypothetical
''Crosbysaurus'' is a genus of extinct archosauromorph that lived in the Late Triassic of Arizona, New Mexico, North Carolina, Texas, and Utah. It is known from the Chinle Formation and Dockum Group rock units from the southwestern United States. The type species is ''C. harrisae'', and the only known material includes teeth. 11 specimens are known, each including a single tooth. ''Crosbysaurus'' was originally identified as an ornithischian dinosaur by Andrew Heckert when it was first described in 2004. Further work has shown that it is likely an archosauromorph based on the features of its teeth, and it may belong to Archosauriformes. The taxon is likely valid as it differs from other genera from the same region known from teeth like '' Revueltosaurus'', '' Tecovasaurus'', ''Krzyzanowskisaurus'', ''Lucianosaurus'', and '' Protecovasaurus''. Description The teeth of ''Crosbysaurus'' are triangular in outline with serrations Serration is a saw-like appearance or a row ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2004 In Paleontology ...
Protozoa New taxa Fungi newly named Plants Newly named plants Arthropoda newly named arachnids Newly named insects Newly named fishes Newly named amphibians Archosauromorphs Newly named dinosaurs Data courtesy of George Olshevsky's dinosaur genera list. Other archosauromorphs Newly named birds Plesiosaurs New taxa Pterosaurs New taxa Synapsids Non-mammalian References {{portal, Paleontology 2000s in paleontology Paleontology Paleontology (), also spelled palaeontology or palæontology, is the scientific study of life that existed prior to, and sometimes including, the start of the Holocene epoch (roughly 11,700 years before present). It includes the study of fossi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Archosauriformes
Archosauriformes (Greek for 'ruling lizards', and Latin for 'form') is a clade of diapsid reptiles that developed from archosauromorph ancestors some time in the Latest Permian (roughly 252 million years ago). It was defined by Jacques Gauthier (1994) as the clade stemming from the last common ancestor of Proterosuchidae and Archosauria (the group that contains crocodiles, pterosaurs and dinosaurs bird.html"_;"title="ncluding_bird">ncluding_birds;_Phil_Senter.html" ;"title="bird">ncluding_birds.html" ;"title="bird.html" ;"title="ncluding bird">ncluding birds">bird.html" ;"title="ncluding bird">ncluding birds; Phil Senter">bird">ncluding_birds.html" ;"title="bird.html" ;"title="ncluding bird">ncluding birds">bird.html" ;"title="ncluding bird">ncluding birds; Phil Senter (2005) defined it as the most exclusive clade containing ''Proterosuchus'' and Archosauria. These reptiles, which include members of the Family (biology), family Proterosuchidae and more advanced forms, were ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Late Triassic
The Late Triassic is the third and final epoch (geology), epoch of the Triassic geologic time scale, Period in the geologic time scale, spanning the time between annum, Ma and Ma (million years ago). It is preceded by the Middle Triassic Epoch and followed by the Early Jurassic Epoch. The corresponding series (stratigraphy), series of rock beds is known as the Upper Triassic. The Late Triassic is divided into the Carnian, Norian and Rhaetian Geologic time scale, Ages. Many of the first dinosaurs evolved during the Late Triassic, including ''Plateosaurus'', ''Coelophysis'', and ''Eoraptor''. The Triassic–Jurassic extinction event began during this epoch and is one of the five major mass extinction events of the Earth. Etymology The Triassic was named in 1834 by Friedrich August von Namoh, Friedrich von Alberti, after a succession of three distinct rock layers (Greek meaning 'triad') that are widespread in southern Germany: the lower Buntsandstein (colourful sandstone'')'', t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ornithischian
Ornithischia () is an extinct order of mainly herbivorous dinosaurs characterized by a pelvic structure superficially similar to that of birds. The name ''Ornithischia'', or "bird-hipped", reflects this similarity and is derived from the Greek stem ' (), meaning "of a bird", and ' (), plural ', meaning "hip joint". However, birds are only distantly related to this group as birds are theropod dinosaurs. Ornithischians with well known anatomical adaptations include the ceratopsians or "horn-faced" dinosaurs (e.g. ''Triceratops''), the pachycephalosaurs or "thick-headed" dinosaurs, the armored dinosaurs (Thyreophora) such as stegosaurs and ankylosaurs, and the ornithopods. There is strong evidence that certain groups of ornithischians lived in herds, often segregated by age group, with juveniles forming their own flocks separate from adults. Some were at least partially covered in filamentous (hair- or feather- like) pelts, and there is much debate over whether these filaments foun ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prehistoric Reptile Genera
Prehistory, also known as pre-literary history, is the period of human history between the use of the first stone tools by hominins 3.3 million years ago and the beginning of recorded history with the invention of writing systems. The use of symbols, marks, and images appears very early among humans, but the earliest known writing systems appeared 5000 years ago. It took thousands of years for writing systems to be widely adopted, with writing spreading to almost all cultures by the 19th century. The end of prehistory therefore came at very different times in different places, and the term is less often used in discussing societies where prehistory ended relatively recently. In the early Bronze Age, Sumer in Mesopotamia, the Indus Valley Civilisation, and ancient Egypt were the first civilizations to develop their own scripts and to keep historical records, with their neighbors following. Most other civilizations reached the end of prehistory during the following Iron Age. T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prehistoric Archosauriforms
Prehistory, also known as pre-literary history, is the period of human history between the use of the first stone tools by hominins 3.3 million years ago and the beginning of recorded history with the invention of writing systems. The use of symbols, marks, and images appears very early among humans, but the earliest known writing systems appeared 5000 years ago. It took thousands of years for writing systems to be widely adopted, with writing spreading to almost all cultures by the 19th century. The end of prehistory therefore came at very different times in different places, and the term is less often used in discussing societies where prehistory ended relatively recently. In the early Bronze Age, Sumer in Mesopotamia, the Indus Valley Civilisation, and ancient Egypt were the first civilizations to develop their own scripts and to keep historical records, with their neighbors following. Most other civilizations reached the end of prehistory during the following Iron Age. T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Serrations
Serration is a saw-like appearance or a row of sharp or tooth-like projections. A serrated cutting edge has many small points of contact with the material being cut. By having less contact area than a smooth blade or other edge, the applied pressure at each point of contact is greater and the points of contact are at a sharper angle to the material being cut. This causes a cutting action that involves many small splits in the surface of the material being cut, which cumulatively serve to cut the material along the line of the blade. In nature, serration is commonly seen in the cutting edge on the teeth of some species, usually sharks. However, it also appears on non-cutting surfaces, for example in botany where a toothed leaf margin or other plant part, such as the edge of a carnation petal, is described as being serrated. A serrated leaf edge may reduce the force of wind and other natural elements. Probably the largest serrations on Earth occur on the skylines of mountains (th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Protecovasaurus
''Protecovasaurus'' is a genus of archosaurian reptile from the Late Triassic of the southwestern United States. It was initially described as a basal ornithischian dinosaur, but was redescribed as a non-dinosaurian archosaur by Irmis ''et al.'' (2006). The type species, ''Protecovasaurus lucasi'', was formally described by Andrew B. Heckert in 2004. Its name, ''Protecovasaurus'', means "before '' Tecovasaurus''". Tecovas was the formation the holotype A holotype is a single physical example (or illustration) of an organism, known to have been used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of several ... specimen was found in. References * Heckert, A. B. (2004). Late Triassic microvertebrates from the lower Chinle Group (Otischalkian-Adamanian: Carnian), southwestern U.S.A. New Mexico Museum of Natural History and Science, Bulletin 27, 170 p. * Irmis, R.B., Parker, W.G., Nesbitt ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lucianosaurus
''Lucianosaurus'' is an extinct genus of amniote of unknown affinities, known only from teeth. Initially described as a basal ornithischian dinosaur, subsequently reclassified as a member of the clade Archosauriformes of uncertain phylogenetic placementIrmis, R.B., Parker, W.G., Nesbitt, S.J., and Liu, J. (2006). Early ornithischian dinosaurs: the Triassic record. ''Historical Biology'' 19(1):3-22. and later, taking into account the similarity of its teeth to the teeth of traversodontid cynodonts such as '' Dadadon'' (shared presence of teeth with sub-triangular crowns, enlarged denticles, and thecodont tooth implantation), as an amniote of uncertain affinities (though based on dissimilarities in gross morphology and geographic separation it is still more likely that the taxon is indeed an archosauriform rather than a traversodontid). Fossil remains of Lucianosaurus were first found in Late Triassic strata in Eastern New Mexico, United States.Hunt, A.P. and Lucas, S.G. 1994. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Krzyzanowskisaurus
''Krzyzanowskisaurus'' (meaning "Stan Krzyżanowski's lizard") is the name given to a genus of archosaur from the Late Triassic-aged Chinle Formation and it is a tooth taxon, based on fossils only of teeth (such as the holotype tooth NMMNH P-29357) and these teeth have been found in the U.S. states of Arizona (including the type locality) and New Mexico. The original report described it as a "probable ornithischian" and Heckert (2005) suggests that ''Krzyzanowskisaurus'' teeth have biostratigraphic utility as an index fossil of the St. Johnsian sub-LVF (land-vertebrate faunachron). The type species, ''Krzyzanowskisaurus hunti'', was reevaluated by Heckert in 2005,Heckert, A.B., (2005). ''Krzyzanowskisaurus'', a new name for a probable ornithischian dinosaur from the Upper Triassic Chinle Group, Arizona and New Mexico, USA. ''New Mexico Museum of Natural History and Science Bulletin'' 29: 77-83. after previously being described by him as ''Revueltosaurus hunti'' in 2002. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tecovasaurus
''Tecovasaurus'' (te-KOH-va-SAWR-us) is an extinct Late Triassic amniote genus of unknown affinities, known only from teeth. It was initially described as a basal ornithischian dinosaur, subsequently reclassified as a member of the clade Archosauriformes of uncertain phylogenetic placement (Irmis ''et al.'' (2007), and later, taking into account the similarity of its teeth to the teeth of traversodontid cynodonts such as '' Dadadon'' (shared presence of teeth with sub-triangular crowns, enlarged denticles, and thecodont tooth implantation), as an amniote of uncertain affinities (Kammerer ''et al.'', 2012; though "based on dissimilarities in gross morphology and geographic separation" the authors considered it more likely that the taxon is indeed an archosauriform rather than a traversodontid). It is named after the Tecovas Formation, in Texas and Arizona, which yielded the holotype A holotype is a single physical example (or illustration) of an organism, known to have been used ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
