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Hazhenia
''Hazhenia'' is an extinct genus of therocephalian therapsids from the Early Triassic of China, of which ''Hazhenia concava'' is the only species. ''Hazhenia'' was named in 1981 from the Heshanggou Formation in the Ordos Desert of Inner Mongolia. It lived during the Olenekian Age of the Early Triassic, about 247 million years ago. ''Hazhenia'' belongs to a group of therocephalians called Baurioidea and possesses many mammal-like features such as cusped teeth and a secondary palate, both of which evolved independently in baurioids. Within Baurioidea it is most closely related to the genus '' Ordosiodon'', which is also known from Inner Mongolia but comes from the slightly younger Ermaying Formation. Both genera were once placed in the family Ordosiidae, but as the name is preoccupied by a family of Cambrian trilobites, it is no longer valid. ''Hazhenia'' is known from a single skull that was discovered by a group from the Institute of Vertebrate Paleontology and Paleoanthropolog ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bauriidae
Bauriidae is an extinct family of therocephalian therapsids. Bauriids were the latest-surviving group of therocephalians after the Permian–Triassic extinction event, going extinct in the Middle Triassic. They are among the most advanced eutherocephalians and possess several mammal-like features such as a secondary palate and wide postcanine teeth at the back of the jaws (analogous to mammalian molars). Unlike other therocephalians, bauriids were herbivorous. They were also smaller than earlier members of the group. Two subfamilies are classified within Bauriidae: Nothogomphodontinae and Bauriinae. Description Bauriids have a dentition characteristic of herbivores with the exception of '' Nothogomphodon''. There are four incisors on either side of the upper jaw. Like other therocephalians, bauriids have moderately enlarged canines. The postcanine teeth behind the canines are broad. The postcanines of the upper and lower jaw fit tightly together as an adaptation to processing ... [...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] |
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] |
Baurioidea
Baurioidea is a superfamily of therocephalian therapsids. It includes advanced therocephalians such as ''Regisaurus'' and ''Bauria''. The superfamily was named by South African paleontologist Robert Broom in 1911. Bauriamorpha, named by D. M. S. Watson and Alfred Romer in 1956, is a junior synonym of Baurioidea. Many baurioids were once placed in a group called Scaloposauria. Scaloposaurs were characterized by their small size and reduced postorbital bar (a strut of bone behind the eye socket). Scaloposauria is no longer recognized as a valid taxon because it likely represents juvenile forms of many groups of therocephalians. Most scaloposaurs, including '' Scaloposaurus'' and ''Regisaurus'', are now classified in various positions within Bauroidea. Many therocephalians once classified as scaloposaurians are now considered basal baurioids. The classification of these species is uncertain, as there have been no comprehensive phylogenetic analyses of scaloposaurian taxa. The v ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Scaloposauria
Baurioidea is a superfamily of therocephalian therapsids. It includes advanced therocephalians such as '' Regisaurus'' and ''Bauria''. The superfamily was named by South African paleontologist Robert Broom in 1911. Bauriamorpha, named by D. M. S. Watson and Alfred Romer in 1956, is a junior synonym of Baurioidea. Many baurioids were once placed in a group called Scaloposauria. Scaloposaurs were characterized by their small size and reduced postorbital bar (a strut of bone behind the eye socket). Scaloposauria is no longer recognized as a valid taxon because it likely represents juvenile forms of many groups of therocephalians. Most scaloposaurs, including ''Scaloposaurus'' and ''Regisaurus'', are now classified in various positions within Bauroidea. Many therocephalians once classified as scaloposaurians are now considered basal baurioids. The classification of these species is uncertain, as there have been no comprehensive phylogenetic analyses of scaloposaurian taxa. The validi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Early Triassic
The Early Triassic is the first of three epochs of the Triassic Period of the geologic timescale. It spans the time between Ma and Ma (million years ago). Rocks from this epoch are collectively known as the Lower Triassic Series, which is a unit in chronostratigraphy. The Early Triassic is the oldest epoch of the Mesozoic Era. It is preceded by the Lopingian Epoch (late Permian, Paleozoic Era) and followed by the Middle Triassic Epoch. The Early Triassic is divided into the Induan and Olenekian ages. The Induan is subdivided into the Griesbachian and Dienerian subages and the Olenekian is subdivided into the Smithian and Spathian subages. The Lower Triassic series is coeval with the Scythian Stage, which is today not included in the official timescales but can be found in older literature. In Europe, most of the Lower Triassic is composed of Buntsandstein, a lithostratigraphic unit of continental red beds. The Early Triassic and partly also the Middle Triassic span the in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Phylogenetic Analysis
In biology, phylogenetics (; from Greek φυλή/ φῦλον [] "tribe, clan, race", and wikt:γενετικός, γενετικός [] "origin, source, birth") is the study of the evolutionary history and relationships among or within groups of organisms. These relationships are determined by Computational phylogenetics, phylogenetic inference methods that focus on observed heritable traits, such as DNA sequences, protein amino acid sequences, or morphology. The result of such an analysis is a phylogenetic tree—a diagram containing a hypothesis of relationships that reflects the evolutionary history of a group of organisms. The tips of a phylogenetic tree can be living taxa or fossils, and represent the "end" or the present time in an evolutionary lineage. A phylogenetic diagram can be rooted or unrooted. A rooted tree diagram indicates the hypothetical common ancestor of the tree. An unrooted tree diagram (a network) makes no assumption about the ancestral line, and does n ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Synapomorphy
In phylogenetics, an apomorphy (or derived trait) is a novel character or character state that has evolved from its ancestral form (or plesiomorphy). A synapomorphy is an apomorphy shared by two or more taxa and is therefore hypothesized to have evolved in their most recent common ancestor. ) In cladistics, synapomorphy implies homology. Examples of apomorphy are the presence of erect gait, fur, the evolution of three middle ear bones, and mammary glands in mammals but not in other vertebrate animals such as amphibians or reptiles, which have retained their ancestral traits of a sprawling gait and lack of fur. Thus, these derived traits are also synapomorphies of mammals in general as they are not shared by other vertebrate animals. Etymology The word —coined by German entomologist Willi Hennig—is derived from the Ancient Greek words (''sún''), meaning "with, together"; (''apó''), meaning "away from"; and (''morphḗ''), meaning "shape, form". Clade analysis T ... [...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] |
Scylacosauria
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, the most basal therocephalian family. Thus, Scylacosauria includes all therocephalians except lycosuchids. Below is a 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 d ... 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] |
Lycosuchus Vanderrieti
''Lycosuchus'' ("wolf crocodile") is an extinct genus of carnivorous therocephalians which lived in the Middle Permian 265—260 Ma existing for approximately . As a member of the Lycosuchidae, the genus represents one of the earliest diverging therocephalians. The type species ''Lycosuchus vanderrieti'' is known from a handful of well-preserved specimens featuring the cranium and lower jaw; the holotype US D173 housed at the University of Stellenbosch, South Africa, is a near complete occluded skull. Specimen MB.R. 995, housed at the Museum für Naturkunde Berlin, Germany, consists of a near complete and isolated lower jaw, along with a partial snout and brain case. With the help of μCT data, Pusch et al (2020) described the endocranial anatomy of ''Lycosuchus vanderrieti''. It was a medium-sized predator, reaching 1.2 m (3.8 ft) in length with a skull 23 cm long., typical of early therocephalians. ''L. vanderrieti'' bore two functional canines in each maxilla, ... [...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] |
