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Diademodon
''Diademodon'' is an extinct genus of cynodonts. It was about long. Discovery Harry Seeley had found his fossil in the Burgersdorp Formation of the Beaufort Group in the Karoo Basin of South Africa. As late as 1988, ''Diademodon'' had been considered a Gophodont due to its transversely expanded cheek teeth, however, it has since been placed in the Cynodont order due to significant differences in skull morphology. Additional species were named by paleontologist A. S. Brink in 1979, although they are now considered synonyms of the type species ''Diademodon tetragonus''. Fossils of the ''Diademodon tetragonus'' have more recently been found in the Omingonde Formation of Namibia, the Fremouw Formation of Antarctica, the Ntawere Formation of Zambia and the Río Seco de la Quebrada Formation in Mendoza Province, Argentina. Although ''Diademodon'' is the most well accepted name for the genera to date, it was originally named ''Cynochampsa laniarius'' by Owen in 1860. The proposed ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diademodon NT
''Diademodon'' is an extinct genus of cynodonts. It was about long. Discovery Harry Seeley had found his fossil in the Burgersdorp Formation of the Beaufort Group in the Karoo Basin of South Africa. As late as 1988, ''Diademodon'' had been considered a Gophodont due to its transversely expanded cheek teeth, however, it has since been placed in the Cynodont order due to significant differences in skull morphology. Additional species were named by paleontologist A. S. Brink in 1979, although they are now considered synonyms of the type species ''Diademodon tetragonus''. Fossils of the ''Diademodon tetragonus'' have more recently been found in the Omingonde Formation of Namibia, the Fremouw Formation of Antarctica, the Ntawere Formation of Zambia and the Río Seco de la Quebrada Formation in Mendoza Province, Argentina. Although ''Diademodon'' is the most well accepted name for the genera to date, it was originally named ''Cynochampsa laniarius'' by Owen in 1860. The prop ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Burgersdorp Formation
The ''Cynognathus'' Assemblage Zone is a tetrapod biozone utilized in the Karoo Basin of South Africa. It is equivalent to the Burgersdorp Formation, the youngest lithostratigraphic formation in the Beaufort Group, which is part of the fossiliferous and geologically important Karoo Supergroup. The ''Cynognathus'' Assemblage Zone is the youngest of the eight biozones found in the Beaufort Group, and is considered to be late Early Triassic (Olenekian) to early Middle Triassic (Anisian) in age (around 247 Ma). The name of the biozone refers to '' Cynognathus crateronotus'', a large and carnivorous cynodont therapsid which occurs throughout the entire biozone. History The first fossils to be found in the Beaufort Group rocks that encompass the current eight biozones were discovered by Andrew Geddes Bain in 1856. However, it was not until 1892 that it was observed that the geological strata of the Beaufort Group could be differentiated based on their fossil taxa. The initial underta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Río Seco De La Quebrada Formation
The Río Seco de la Quebrada Formation is a Triassic geological formation in Mendoza Province, Argentina. Fossils of cynodonts such as '' Cynognathus, Diademodon,'' and ''Pascualgnathus'' have been found in this formation, along with dicynodonts such as ''Vinceria'' and '' Acratophorus''. Based on biostratigraphy, the Río Seco de la Quebrada Formation is considered to have formed during the Anisian stage, as it shares fauna with the upper subzones of the ''Cynognathus'' Assemblage Zone in South Africa. However, radiometric dating controversially argues that it was deposited during the early Carnian stage, 10 million years younger than expected otherwise. Geology The Río Seco de la Quebrada Formation (RSQ) is the younger of the two formations in the Puesto Viejo Group, overlying the older Quebrada de los Fósiles Formation (QF). The Puesto Viejo Group is a geologically isolated succession of Triassic sedimentary and igneous rock exposed in the area of the San Rafael Block. ... [...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] |
Trirachodon
''Trirachodon'' (Greek: "three ridge tooth") is an extinct genus of cynodonts. Fossils have been found in the ''Cynognathus'' Assemblage Zone of the Beaufort Group in South Africa and the Omingonde Formation of Namibia, dating back to the Early and Middle Triassic. Description The skull of ''Trirachodon'' had a short, narrow snout with a wide orbital region. The zygomatic arches were relatively slender. ''Trirachodon'' was quite small for a cynodont, growing no larger than 50 cm in length. It had noticeably less molariform teeth than its closely related contemporary ''Diademodon''. These teeth tended to be transversely broader than ''Diademodon'' as well. A bony secondary palate and precise postcanine tooth occlusion are seen as derived characteristics in ''Trirachodon'' that are similar to those of mammals. Species The type species is ''T. berryi'', named in 1895 on the basis of a single cranial skeleton. Three other specimens were later referred to ''T. kannemeyeri'', wh ... [...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] |
Ntawere Formation
The Ntawere Formation is a Middle Triassic (Anisian) geological formation in Zambia, preserving fossils of synapsids, archosaurs, and temnospondyls. Geology Several different facies are present in the Ntawere Formation, reconstructing a floodplain environment. The coarsest facies are trough cross-bedded conglomeratic sandstone full of mineral concretions. These coarse deposits formed in ancient channels such as riverbeds. Another type of facies involves thick beds of mudstone interbedding with thinner layers of fine-grained sandstone, indicating alternating low- and high-energy water flow within the channels. Graded sandstone to mudstone overbank deposits (complete with ripple marks) occur near channel deposits. Extensive successions of laminated or massive mudstone are common, often containing slickensides, calcareous nodules or layers (marls), and/or hematite nodules. These types of thick mud/marl layers likely formed in more quiet parts of the floodplain isolated from turbu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cynognathians
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] |
Fremouw Formation
The Fremouw Formation is a Triassic-age rock formation in the Transantarctic Mountains of Antarctica. It contains the oldest known fossils of tetrapods from Antarctica, including synapsids, reptiles and amphibians. Fossilized trees have also been found. The formation's beds were deposited along the banks of rivers and on floodplains. During the Triassic, the area would have been a riparian forest at 70–75°S latitude. Stratigraphy The Fremouw Formation is mostly Triassic in age, with the oldest rocks dating back to the latest Permian. Much of the formation is quartzose sandstone that was deposited in stream beds. It overlies the Permian Buckley Formation, which consists of coal and ''Glossopteris'' fossils. The formation is informally divided into lower, middle, and upper units. Most fossils are found in the Lower Fremouw Formation. Here, bones are preserved in fine grained siltstones and mudstones, coarse grained channel sandstones, and conglomerates. Paleoenvironment W ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cynognathus
''Cynognathus'' is an extinct genus of large-bodied cynodontian therapsids that lived in the Middle Triassic. It is known from a single species, ''Cynognathus crateronotus''. ''Cynognathus'' was a long predator closely related to mammals and had a southern hemispheric distribution. Fossils have so far been recovered from South Africa, Argentina, Antarctica, and Namibia. Description ''Cynognathus'' was a heavily built animal, and measured around in snout-to-vent body length. It had a particularly large head, up to in length, with wide jaws and sharp teeth. Its hindlimbs were placed directly beneath the body, but the forelimbs sprawled outwards in a more reptilian fashion. This form of double (erect/sprawling) gait is also found in some primitive mammals alive today. Possible autapomorphies of ''C. crateronotus'' include an extremely elongated postorbital bar and sectorial postcanine teeth with two serrated cusps distal to a recurved apex. Discovery and naming During 18 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Prehistoric Cynodont 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] |
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] |
