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Scylacosaur
Scylacosauria is a clade of therocephalian therapsids. It includes the basal family Scylacosauridae and the infraorder Eutherocephalia. Scylacosauridae and Eutherocephalia form this clade to the exclusion of Lycosuchidae Lycosuchidae is an extinct family of therocephalian therapsids from the Middle Permian Beaufort Group of South Africa. It currently contains two monotypic genera, ''Lycosuchus'', represented by ''L. vanderrieti'', which was named by paleontologis ..., the most basal therocephalian family. Thus, Scylacosauria includes all therocephalians except lycosuchids. Below is a cladogram showing the phylogenetic position of Sylacosauria: References Therocephalia Guadalupian first appearances Middle Triassic extinctions Tetrapod unranked clades {{paleo-Therapsid-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Eutherocephalia
Eutherocephalia ("true beast head") is an extinct clade of advanced therocephalian therapsids. Eutherocephalians are distinguished from the lycosuchids and scylacosaurids, two early therocephalian families. While lycosuchids and scyalosaurids became extinct by the end of the Permian period, eutherocephalians survived the Permian–Triassic extinction event. The group eventually became extinct in the Middle Triassic. Characteristics The Eutherocephalians evolved several mammal-like traits through convergent evolution with Cynodontia. Among those traits were the loss of palatine teeth and the reduction of the parietal eye. The latter organ is instrumental in thermoregulation among lizards and snakes, indicating both eutherocephalians and cynodonts were evolving toward a more active, homeothermic lifestyle, though the eye never fully disappeared in the eutherocephalians. Classification The clade Eutherocephalia contains the majority of therocephalians, yet the phylogenetic rela ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Middle Permian
The Guadalupian is the second and middle series/epoch of the Permian. The Guadalupian was preceded by the Cisuralian and followed by the Lopingian. It is named after the Guadalupe Mountains of New Mexico and Texas, and dates between 272.95 ± 0.5 – 259.1 ± 0.4 Mya. The series saw the rise of the therapsids, a minor extinction event called Olson's Extinction and a significant mass extinction called the end-Capitanian extinction event. The Guadalupian was previously known as the Middle Permian. Name and background The Guadalupian is the second and middle series or epoch of the Permian. Previously called Middle Permian, the name of this epoch is part of a revision of Permian stratigraphy for standard global correlation. The name "Guadalupian" was first proposed in the early 1900s, and approved by the International Subcommission on Permian Stratigraphy in 1996. References to the Middle Permian still exist. The Guadalupian was preceded by the Cisuralian and followed by the Lop ... [...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] |
Porosteognathus
''Porosteognathus'' is an extinct genus of therocephalian therapsids. Remains have been found at Isheevo in Russia (Republic of Tatarstan The Republic of Tatarstan (russian: Республика Татарстан, Respublika Tatarstan, p=rʲɪsˈpublʲɪkə tətɐrˈstan; tt-Cyrl, Татарстан Республикасы), or simply Tatarstan (russian: Татарстан, tt ...).Michael J. Benton, Mikhail A. Shishkin, David M. Unwin, and Evgenii N. Kurochkin (2003): ''The Age of Dinosaurs in Russia and Mongolia'', Cambridge University Press References Extinct animals of Russia Scylacosaurids Therocephalia genera Fossil taxa described in 1955 {{paleo-therapsid-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1994 In Paleontology
Plants Conifers Angiosperms Arthropods Insects Molluscs Bivalves Fishes Newly named bony fishes Archosauromorphs * Aff. Rebbachisaurus gastroliths documented.Calvo (1994). Sanders, Manley, and Carpenter (2001), "Table 12.1" page 167. * The "Talkeetna Mountains Hadrosaur" specimen was discovered in a quarry being excavated for road material. The quarry is near the Glenn Highway, approximately 150 miles northeast of Anchorage. That fall, excavation began, and was resumed in the summer of 1996. Newly named pseudosuchians Newly named basal dinosauromorphs Newly named dinosaurs Data courtesy of George Olshevsky's dinosaur genera list. Birds Plesiosaurs * Plesiosaur gastroliths documented.Martin (1994). Sanders, Manley, and Carpenter (2001), "Table 12.1" page 167. New taxa Pterosaurs New taxa Other diapsids New taxa Footnotes {{Reflist, , refs= "Introduction," in Pasche and May (2001); page 220. "Location and Geologic Setting," in Pasche and May (2001) ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scylacosauridae
Scylacosauridae is an extinct family of therocephalian therapsids. Scylacosaurids lived during the Permian period and were among the most basal therocephalians. The family was named by South African paleontologist Robert Broom in 1903. Scylacosaurids have long snouts and unusual saber-like canine teeth. References External links Scylacosauridaein the Paleobiology Database The Paleobiology Database is an online resource for information on the distribution and classification of fossil animals, plants, and microorganisms. History The Paleobiology Database (PBDB) originated in the NCEAS-funded Phanerozoic Marine Pale ... Guadalupian first appearances Lopingian extinctions Prehistoric therapsid families {{paleo-Therapsid-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Clade
A clade (), also known as a monophyletic group or natural group, is a group of organisms that are monophyletic – that is, composed of a common ancestor and all its lineal descendants – on a phylogenetic tree. Rather than the English term, the equivalent Latin term ''cladus'' (plural ''cladi'') is often used in taxonomical literature. The common ancestor may be an individual, a population, or a species (extinct or extant). Clades are nested, one in another, as each branch in turn splits into smaller branches. These splits reflect evolutionary history as populations diverged and evolved independently. Clades are termed monophyletic (Greek: "one clan") groups. Over the last few decades, the cladistic approach has revolutionized biological classification and revealed surprising evolutionary relationships among organisms. Increasingly, taxonomists try to avoid naming taxa that are not clades; that is, taxa that are not monophyletic. Some of the relationships between organisms ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Therocephalia
Therocephalia is an extinct suborder of eutheriodont therapsids (mammals and their close relatives) from the Permian and Triassic. The therocephalians ("beast-heads") are named after their large skulls, which, along with the structure of their teeth, suggest that they were carnivores. Like other non-mammalian synapsids, therocephalians were once described as "mammal-like reptiles". Therocephalia is the group most closely related to the cynodonts, which gave rise to the mammals. This relationship takes evidence in a variety of skeletal features. The fossils of therocephalians are numerous in the Karoo of South Africa, but have also been found in Russia, China, Tanzania, Zambia, and Antarctica. Early therocephalian fossils discovered in Middle Permian deposits of South Africa support a Gondwanan origin for the group, which seems to have spread quickly across Earth. Although almost every therocephalian lineage ended during the great Permian–Triassic extinction event, a few represe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Therapsid
Therapsida is a major group of eupelycosaurian synapsids that includes mammals, their ancestors and relatives. Many of the traits today seen as unique to mammals had their origin within early therapsids, including limbs that were oriented more underneath the body, as opposed to the sprawling posture of many reptiles and salamanders. Therapsids evolved from "pelycosaurs", specifically within the Sphenacodontia, more than 279.5 million years ago. They replaced the "pelycosaurs" as the dominant large land animals in the Middle Permian through to the Early Triassic. In the aftermath of the Permian–Triassic extinction event, therapsids declined in relative importance to the rapidly diversifying reptiles during the Middle Triassic. The therapsids include the cynodonts, the group that gave rise to mammals ( Mammaliaformes) in the Late Triassic, around 225 million years ago. Of the non-mammalian therapsids, only cynodonts survived beyond the end of the Triassic, with the only other ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Basal (phylogenetics)
In phylogenetics, basal is the direction of the ''base'' (or root) of a phylogenetic tree#Rooted tree, rooted phylogenetic tree or cladogram. The term may be more strictly applied only to nodes adjacent to the root, or more loosely applied to nodes regarded as being close to the root. Note that extant taxa that lie on branches connecting directly to the root are not more closely related to the root than any other extant taxa. While there must always be two or more equally "basal" clades sprouting from the root of every cladogram, those clades may differ widely in taxonomic rank, Phylogenetic diversity, species diversity, or both. If ''C'' is a basal clade within ''D'' that has the lowest rank of all basal clades within ''D'', ''C'' may be described as ''the'' basal taxon of that rank within ''D''. The concept of a 'key innovation' implies some degree of correlation between evolutionary innovation and cladogenesis, diversification. However, such a correlation does not make a given ca ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Family (biology)
Family ( la, familia, plural ') is one of the eight major hierarchical taxonomic ranks in Linnaean taxonomy. It is classified between order and genus. A family may be divided into subfamilies, which are intermediate ranks between the ranks of family and genus. The official family names are Latin in origin; however, popular names are often used: for example, walnut trees and hickory trees belong to the family Juglandaceae, but that family is commonly referred to as the "walnut family". What belongs to a family—or if a described family should be recognized at all—are proposed and determined by practicing taxonomists. There are no hard rules for describing or recognizing a family, but in plants, they can be characterized on the basis of both vegetative and reproductive features of plant species. Taxonomists often take different positions about descriptions, and there may be no broad consensus across the scientific community for some time. The publishing of new data and opini ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lycosuchidae
Lycosuchidae is an extinct family of therocephalian therapsids from the Middle Permian Beaufort Group of South Africa. It currently contains two monotypic genera, ''Lycosuchus'', represented by ''L. vanderrieti'', which was named by paleontologist Robert Broom in 1903, and '' Simorhinella'', represented by ''S. baini'', which was named by Broom in 1915. Both species are characterized by their large body sizes and short, deep snouts. Two sets of enlarged canine teeth 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 howeve ... were once regarded as a defining feature of lycosuchids, but recent studies have proposed that the front-most pair are replacements for the ones behind them, which would have eventually fallen out as individuals aged. Lycosuchids are the earliest known therocephalians a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
