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Kataigidodon
''Kataigidodon'' ("thunderstorm tooth") is an extinct genus of eucynodont cynodont therapsid that was discovered in the Chinle Formation of Arizona.Kligman, B.T.; Marsh, A.D.; Sues, H.D.; Sidor, C.A.; 2020 "A new non-mammalian eucynodont from the Chinle Formation (Triassic: Norian), and implications for the early Mesozoic equatorial cynodont record": Biological Letters. https://doi.org/10.1098/rsbl.2020.0631 It is a monotypic genus, with only type species ''Kataigidodon venetus'' known. Description The large mental foramen of ''Kataigidodon venetus'' is anteroposteriorly longer than it is tall. It opens on the lateral side of the dentary below the first and second postcanine Cheek teeth or post-canines comprise the molar and premolar teeth in mammals. Cheek teeth are multicuspidate (having many folds or tubercles). Mammals have multicuspidate molars (three in placentals, four in marsupials, in each jaw quadrant) and p ... teeth. The mental foramen is at the anterior end of a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
2020 In Paleontology
Plants Sponges Cnidarians New taxa Research * Revision of tabulate-like fossils from before the latest Middle Ordovician is published by Elias, Lee & Pratt (2020), who reject the interpretation of these fossils as true tabulate corals. * Drake, Whitelegge & Jacobs (2020) report the first recovery, sequencing, and identification of fossil biomineral proteins from a Pleistocene fossil invertebrate (the stony coral ''Orbicella annularis''). Arthropods Bryozoans Brachiopods New taxa Research * A study on the mode of life of Paleozoic strophomenatans is published by Stanley (2020), who argues that nearly all strophomenatans lived infaunally. * A study on the paleobiogeography of Early−Middle Devonian (Pragian−Eifelian) brachiopods from West Gondwana, aiming to determine any potential controls that may have driven bioregionalization, is published by Penn-Clarke & Harper (2020). * A study on the phylogenetic relationships and ecomorphologic diversification of Mesozoi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eucynodont
Eucynodontia ("true dog teeth") is a clade of cynodont therapsids including mammals and most non-mammalian cynodonts. The oldest eucynodonts are known from the Early Triassic and possibly Late Permian. Eucynodontia includes two major subgroups, Cynognathia and Probainognathia. The clade was named in 1982 by Thomas Kemp, who defined it as all cynodonts more derived than '' Thrinaxodon''. In 2001, Hopson and Kitching redefined the clade Eucynodontia as the least inclusive group containing Mammalia Mammals () are a group of vertebrate animals constituting the class Mammalia (), characterized by the presence of mammary glands which in females produce milk for feeding (nursing) their young, a neocortex (a region of the brain), fur o ... and '' Exaeretodon''.James A. Hopson and James W. Kitching, 2001, "A Probainognathian Cynodont from South Africa and the Phylogeny of Nonmammalian Cynodonts" pp 5-35 in: PARISH A. JENKINS, JR., MICHAEL D. SHAPIRO, AND TOMASZ OWERKOWICZ ... [...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] |
Norian
The Norian is a division of the Triassic Period. It has the rank of an age (geochronology) or stage (chronostratigraphy). It lasted from ~227 to million years ago. It was preceded by the Carnian and succeeded by the Rhaetian. Stratigraphic definitions The Norian was named after the Noric Alps in Austria. The stage was introduced into scientific literature by Austrian geologist Edmund Mojsisovics von Mojsvar in 1869. The Norian Stage begins at the base of the ammonite biozones of '' Klamathites macrolobatus'' and '' Stikinoceras kerri'', and at the base of the conodont biozones of '' Metapolygnathus communisti'' and '' Metapolygnathus primitius''. A global reference profile for the base (a GSSP) had in 2009 not yet been appointed. The top of the Norian (the base of the Rhaetian) is at the first appearance of ammonite species '' Cochloceras amoenum''. The base of the Rheatian is also close to the first appearance of conodont species '' Misikella spp.'' and '' Epigondolella mo ... [...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] |
Cynodont
The cynodonts () (clade Cynodontia) are a clade of eutheriodont therapsids that first appeared in the Late Permian (approximately 260 mya), and extensively diversified after the Permian–Triassic extinction event. Cynodonts had a wide variety of lifestyles, including carnivory and herbivory. Mammals are cynodonts, as are their extinct ancestors and close relatives, having evolved from advanced probainognathian cynodonts during the Late Triassic. All other cynodont lines went extinct, with the last known non-mammalian cynodont group, the Tritylodontidae, having its youngest records in the Early Cretaceous. Description Early cynodonts have many of the skeletal characteristics of mammals. The teeth were fully differentiated and the braincase bulged at the back of the head. Outside of some crown-group mammals (notably the therians), all cynodonts probably laid eggs. The temporal fenestrae were much larger than those of their ancestors, and the widening of the zygomatic arch in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Chinle Formation
The Chinle Formation is an Upper Triassic continental geological formation of fluvial, lacustrine, and palustrine to eolian deposits spread across the U.S. states of Nevada, Utah, northern Arizona, western New Mexico, and western Colorado. In New Mexico, it is often raised to the status of a geological group, the Chinle Group. Some authors have controversially considered the Chinle to be synonymous to the Dockum Group of eastern Colorado and New Mexico, western Texas, the Oklahoma panhandle, and southwestern Kansas. The Chinle Formation is part of the Colorado Plateau, Basin and Range, and the southern section of the Interior Plains.GEOLEX database entry for Chinle USGS (viewed 19 March 2006) A probable separate depositional basin within the Chinle is found in northwestern Colorado and northeastern Ut ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
The Arizona Republic
''The Arizona Republic'' is an American daily newspaper published in Phoenix. Circulated throughout Arizona, it is the state's largest newspaper. Since 2000, it has been owned by the Gannett newspaper chain. Copies are sold at $2 daily or at $3 on Sundays and $5 on Thanksgiving Day; prices are higher outside Arizona. History Early years The newspaper was founded May 19, 1890, under the name ''The Arizona Republican''. Dwight B. Heard, a Phoenix land and cattle baron, ran the newspaper from 1912 until his death in 1929. The paper was then run by two of its top executives, Charles Stauffer and W. Wesley Knorpp, until it was bought by Midwestern newspaper magnate Eugene C. Pulliam in 1946. Stauffer and Knorpp had changed the newspaper's name to ''The Arizona Republic'' in 1930, and also had bought the rival ''Phoenix Evening Gazette'' and ''Phoenix Weekly Gazette'', later known, respectively, as ''The Phoenix Gazette'' and the ''Arizona Business Gazette''. Pulliam era Pulliam, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mental Foramen
The mental foramen is one of two foramina (openings) located on the anterior surface of the mandible. It is part of the mandibular canal. It transmits the terminal branches of the inferior alveolar nerve and the mental vessels. Structure The mental foramen is located on the anterior surface of the mandible. It is directly below the commisure of the lips, and the tendon of depressor labii inferioris muscle. It is at the end of the mandibular canal, which begins at the mandibular foramen on the posterior surface of the mandible. It transmits the terminal branches of the inferior alveolar nerve (the mental nerve), the mental artery, and the mental vein. Variation The mental foramen descends slightly in toothless individuals. The mental foramen is in line with the longitudinal axis of the 2nd premolar in 63% of people. It generally lies at the level of the vestibular fornix and about a finger's breadth above the inferior border of the mandible. In the general population, 17% ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Postcanine
Cheek teeth or post-canines comprise the molar and premolar teeth in mammals. Cheek teeth are multicuspidate (having many folds or tubercles). Mammals have multicuspidate molars (three in placentals, four in marsupials, in each jaw quadrant) and premolars situated between canines and molars whose shape and number varies considerably among particular groups. For example, many modern Carnivora possess carnassials, or secodont teeth. This scissor-like pairing of the last upper premolar and first lower molar is adapted for shearing meat. In contrast, the cheek teeth of deer and cattle are selenodont. Viewed from the side, these teeth have a series of triangular cusps or ridges, enabling the ruminants' sideways jaw motions to break down tough vegetable matter. Cheek teeth are sometimes separated from the incisors by a gap called a diastema. Cheek teeth in reptiles are much simpler as compared to mammals. Roles and significance Apart from helping grind the food to properly reduce the s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Boreogomphodon
''Boreogomphodon'' is an extinct genus of traversodontid cynodonts from the Late Triassic of the eastern United States. Fossils have been found from the Turkey Branch Formation in Virginia. Description and history ''Boreogomphodon jeffersoni'' was named in 1990. Its teeth and cranial bones are the most common tetrapod fossils in the Turkey Branch Formation. ''Boreogomphodon'' was distinguished from other traversodontids like the African '' Luangwa'' and the South American ''Traversodon'' on the basis of its postcanine teeth. Most traversodontids have lower postcanine teeth with two cusps, but ''Boreogomphodon'' was the first traversodontid found with three cusps on its lower postcanine teeth. There is a single cusp on the side of the upper postcanine facing the lip, while a flat surface extends outward from it. The traversodontid '' Arctotraversodon'' from the Wolfville Formation of Nova Scotia is similar to ''Boreogomphodon'' in that it has three cusps on its lower postcanine, bu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Arctotraversodon
''Arctotraversodon'' is an extinct genus of traversodontid cynodonts from the Late Triassic of Canada. Fossils first described from the Wolfville Formation in Nova Scotia in 1984 represented the first known traversodontid from North America.Hopson, J.A. (1984). Late Triassic traversodont cynodonts from Nova Scotia and southern Africa. ''Palaeontologia Africana'' Vol. 25; 181-201. The type and only species is ''A. plemmyridon'' and is represented by teeth and several dentary bones. Description and history ''Arctotraversodon'' was first tentatively placed in the genus ''Scalenodontoides'' as a new species, ?''Scalenodontoides plemmyridon''. Only dentary bones and a few teeth were known when it was first named. Postcanine teeth, the primary diagnostic material of most traversodontids, were not known for ?''S. plemmyridon''. Few available features could diagnose ?''S. plemmyridon'' as its own species, but the bones and teeth were clearly different from those of other traversodontids. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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