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Etjoia
''Etjoia'' is an extinct genus of traversodontid cynodonts that lived during the Middle Triassic or Late Triassic period in southern Africa. This medium-sized omnivorous cynognathian provides important information on the dental evolution of early diverging gomphodonts and traversodontids. Discovery and etymology ''Etjoia'' was discovered in the upper beds of the Omingonde Formation of Namibia (dated to the Ladinian to Carnian) by American paleontologist Charles Schaff in 1996. The specimen was unearthed on the south-eastern side of the Etjo Mountain, in the Waterberg Basin of the Otjozondjupa region, in central north-west Namibia. The holotype is deposited in the Geological Survey of Namibia of Windhoek with the specimen number GSN F1591. The generic name refers to Mount Etjo from which the new genus was unearthed. The type species, ''E. dentitransitus'', refers to the possession of a transitional dentition with sub-circular upper postcanines and a large number of sectorial te ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Etjoia All Views
''Etjoia'' is an extinct genus of traversodontid cynodonts that lived during the Middle Triassic or Late Triassic period in southern Africa. This medium-sized omnivorous cynognathian provides important information on the dental evolution of early diverging gomphodonts and traversodontids. Discovery and etymology ''Etjoia'' was discovered in the upper beds of the Omingonde Formation of Namibia (dated to the Ladinian to Carnian) by American paleontologist Charles Schaff in 1996. The specimen was unearthed on the south-eastern side of the Etjo Mountain, in the Waterberg Basin of the Otjozondjupa region, in central north-west Namibia. The holotype is deposited in the Geological Survey of Namibia of Windhoek with the specimen number GSN F1591. The generic name refers to Mount Etjo from which the new genus was unearthed. The type species, ''E. dentitransitus'', refers to the possession of a transitional dentition with sub-circular upper postcanines and a large number of sectorial t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Omingonde Formation
The Omingonde Formation is an Early Triassic, Early to Middle Triassic (Anisian to Ladinian) geologic Formation (geology), formation, part of the Karoo Supergroup, in the western Otjozondjupa Region and northeastern Erongo Region of north-central Namibia. The formation has a maximum thickness of about and comprises sandstones, shales, siltstones and conglomerate (geology), conglomerates, was deposited in a fluvial depositional environment, environment, alternating between a meandering river, meandering and braided river setting. The Omingonde Formation is correlated with a series of formations in northwestern Argentina and the Paraná Basin in southeastern Brazil, deposited in a larger basinal area, 120 million years before the break-up of Pangea. The formation has provided fossils of several therapsids, amphibians and ichnofossils and belongs to the Cynognathus Assemblage Zone, ''Cynognathus'' Assemblage Zone. The Omingonde Formation preserves the most diverse fauna of Middle Tria ... [...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] |
Traversodontidae
Traversodontidae is an extinct family of herbivorous cynodonts. Traversodonts were primarily Gondwanan, with many species known from Africa and South America. Recently, traversodonts have also been found from Europe and eastern North America. Traversodonts first appeared in the Middle Triassic and diversified in the Late Triassic before going extinct at the end of the epoch. The family Traversodontidae was erected by Friedrich von Huene in 1936 for cynodonts first found in São Pedro do Sul in Paleorrota, Brazil. Description Traversodonts are members of Gomphodontia, a group of herbivorous cynognathian cynodonts. As an adaptation toward eating plants, they have wide postcanine teeth behind large canines. These postcanines are closely spaced with their crowns touching each other. Each is usually wider than it is long and is covered in several cusps. Because of their complexity, postcanine teeth are the primary means of identifying and distinguishing different species of traverso ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Traversodontid
Traversodontidae is an extinct family of herbivorous cynodonts. Traversodonts were primarily Gondwanan, with many species known from Africa and South America. Recently, traversodonts have also been found from Europe and eastern North America. Traversodonts first appeared in the Middle Triassic and diversified in the Late Triassic before going extinct at the end of the epoch. The family Traversodontidae was erected by Friedrich von Huene in 1936 for cynodonts first found in São Pedro do Sul in Paleorrota, Brazil. Description Traversodonts are members of Gomphodontia, a group of herbivorous cynognathian cynodonts. As an adaptation toward eating plants, they have wide postcanine teeth behind large canines. These postcanines are closely spaced with their crowns touching each other. Each is usually wider than it is long and is covered in several cusps. Because of their complexity, postcanine teeth are the primary means of identifying and distinguishing different species of traverso ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cynognathian
Cynognathia ("dog jaw") is one of two major clades of cynodonts, the other being Probainognathia. Cynognathians included the large carnivorous genus '' Cynognathus'' and the herbivorous traversodontids. Cynognathians can be identified by several synapomorphies including a very deep zygomatic arch that extends above the middle of the orbit. Cynognathian fossils are currently known from Africa, Antarctica, Asia, Europe, North America and South America. Taxonomy *Suborder Cynodontia **Infraorder Eucynodontia ***(unranked) Cynognathia ****Family Cynognathidae *****'' Cynognathus'' ****(unranked) Gomphodontia *****Family Diademodontidae ******'' Diademodon'' ******''Titanogomphodon'' *****(unranked) Neogomphodontia ******Family Trirachodontidae *******Subfamily Trirachodontinae ********'' Langbergia'' ********''Trirachodon'' *******Subfamily Sinognathinae ********''Beishanodon'' ********''Sinognathus'' ********'' Cricodon'' ******Family Traversodontidae *******''Etjoia'' *** ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Middle Triassic
In the geologic timescale, the Middle Triassic is the second of three epochs of the Triassic period or the middle of three series in which the Triassic system is divided in chronostratigraphy. The Middle Triassic spans the time between Ma and Ma (million years ago). It is preceded by the Early Triassic Epoch and followed by the Late Triassic Epoch. The Middle Triassic is divided into the Anisian and Ladinian ages or stages. Formerly the middle series in the Triassic was also known as Muschelkalk. This name is now only used for a specific unit of rock strata with approximately Middle Triassic age, found in western Europe. Middle Triassic fauna Following the Permian–Triassic extinction event, the most devastating of all mass-extinctions, life recovered slowly. In the Middle Triassic, many groups of organisms reached higher diversity again, such as the marine reptiles (e.g. ichthyosaurs, sauropterygians, thallatosaurs), ray-finned fish and many invertebrate groups like ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
PALAIOS
''PALAIOS'' is a bimonthly academic journal dedicated to the study of the impact of life on Earth history, combining the fields of palaeontology and sedimentology. It has been published by the Society for Sedimentary Geology since its inception in 1986. Although not an acronym An acronym is a word or name formed from the initial components of a longer name or phrase. Acronyms are usually formed from the initial letters of words, as in ''NATO'' (''North Atlantic Treaty Organization''), but sometimes use syllables, as ..., the title PALAIOS is capitalized.e.g. References Geology journals Paleontology journals Publications established in 1986 Bimonthly journals {{paleontology-journal-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Canine Tooth
In mammalian oral anatomy, the canine teeth, also called cuspids, dog teeth, or (in the context of the upper jaw) fangs, eye teeth, vampire teeth, or vampire fangs, are the relatively long, pointed teeth. They can appear more flattened however, causing them to resemble incisors and leading them to be called ''incisiform''. They developed and are used primarily for firmly holding food in order to tear it apart, and occasionally as weapons. They are often the largest teeth in a mammal's mouth. Individuals of most species that develop them normally have four, two in the upper jaw and two in the lower, separated within each jaw by incisors; humans and dogs are examples. In most species, canines are the anterior-most teeth in the maxillary bone. The four canines in humans are the two maxillary canines and the two mandibular canines. Details There are generally four canine teeth: two in the upper (maxillary) and two in the lower (mandibular) arch. A canine is placed laterally to ... [...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] |
Denticle (tooth Feature)
Denticles, also called serrations, are small bumps on a tooth that serve to give the tooth a serrated edge. In paleontology, denticle characteristics such as size and density (denticles per unit distance) are used to describe and classify fossilized teeth, especially those of dinosaurs. Denticles are also present on the teeth of varanoid lizards, sharks, and mammals. The term is also used to describe the analogous radular teeth of mollusks. Archived aPDF File:Dromaeosauridae tooth.TIF, Dromaeosauridae tooth with small denticles along the cutting edge. Scale bars are 1 mm. File:Ankylosaurus tooth.jpg, ''Ankylosaurus'' tooth with large denticles. File:Dentary teeth of Segnosaurus.png, ''Segnosaurus ''Segnosaurus'' is a genus of therizinosaurid dinosaur that lived in what is now southeastern Mongolia during the Late Cretaceous, about 102–86 million years ago. Multiple incomplete but well-preserved specimens were discovered in the Go ...'' dentition featuring a tripl ... [...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] |
