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Eolydekkerina
''Eolydekkerina'' is an extinct genus of temnospondyl amphibian from the Early Triassic of South Africa. It belongs to the family Lydekkerinidae, along with the closely related genus ''Lydekkerina''. It is known from a single type species, ''Eolydekkerina magna'', which was named in 1996 from a part of the Beaufort Group called the ''Lystrosaurus'' Assemblage Zone. Description ''Eolydekkerina'' is known from two specimens: a skull lacking the lower jaws and a poorly lower jaw, not associated with the skull. At in length, the skull of ''Eolydekkerina'' is larger than that of any ''Lydekkerina'' specimen. The snout is proportionally much longer, and the eye sockets are placed farther apart than they are in ''Lydekkerina''. The proportions of the skull in ''Eolydekkerina'' are similar to those of the Australian lydekkerinid genus '' Chomatobatrachus''. However, ''Eolydekkerina'' shares more features in common with ''Lydekkerina'', including the nearly identical shape of bones at th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lydekkerinidae
Lydekkerinidae is a family of stereospondyl temnospondyls that lived in the Early Triassic period. During this time period, lydekkerinids were widely distributed, with putative remains reported from Russia, Greenland, India, South Africa, Madagascar, Australia, and Antarctica. In contrast to most other stereospondyls, lydekkerinids were relatively small-bodied (most with skulls less than 10 cm in length). The type genus is ''Lydekkerina'', the namesake of the family and the best-known lydekkerinid. Description The identification of features shared among lydekkerinids (synapomorphies) necessarily varies depending on which taxa are considered to belong to this group (see further in next section). In the most expansive concept, the family includes the eponymous ''Lydekkerina'' (and junior synonyms like '''Broomulus''' and '''Limnoiketes'''), ''Eolydekkerina'' from South Africa, ''Deltacephalus'' from Madagascar, ''Luzocephalus'' from Russia and Greenland (which includes the '''Aqui ... [...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] |
Paedomorphosis
Neoteny (), also called juvenilization,Montagu, A. (1989). Growing Young. Bergin & Garvey: CT. is the delaying or slowing of the physiological, or somatic, development of an organism, typically an animal. Neoteny is found in modern humans compared to other primates. In progenesis or paedogenesis, sexual development is accelerated. Both neoteny and progenesis result in paedomorphism (as having the form typical of children) or paedomorphosis (changing towards forms typical of children), a type of heterochrony. It is the retention in adults of traits previously seen only in the young. Such retention is important in evolutionary biology, domestication and evolutionary developmental biology. Some authors define paedomorphism as the retention of larval traits, as seen in salamanders.Schell, S. C. ''Handbook of Trematodes of North America North of Mexico'', 1985, pg. 22 History and etymology The origins of the concept of neoteny have been traced to the Bible (as argued by Ashley Montag ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Proterosuchus
''Proterosuchus'' is an extinct genus of archosauriform reptiles that lived during the Early Triassic. It contains three valid species: the type species ''P. fergusi'' and the referred species ''P. alexanderi'' and ''P. goweri''. All three species lived in what is now South Africa. The genus was named in 1903 by the South African paleontologist Robert Broom. The well-known genus ''Chasmatosaurus'' is a junior synonym of ''Proterosuchus''. ''Proterosuchus'' was a mid-sized quadrupedal reptile with a sprawling stance that could reach a length of up to . It had a large head and distinctively hooked snout. It was a predator, which may have hunted prey such as ''Lystrosaurus''. The lifestyle of ''Proterosuchus'' remains debated; it may have been terrestrial or it may have been a semiaquatic ambush predator similar to modern crocodiles. ''Proterosuchus'' is one of the earliest members of the clade Archosauriformes, which also includes crocodilians, pterosaurs, and dinosaurs, includin ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Owenetta
''Owenetta'' is an extinct genus of owenettid procolophonian parareptile. Fossils have been found from the Beaufort Group in the Karoo Basin of South Africa. Although most procolophonians lived during the Triassic, ''Owenetta'' existed during the Wuchiapingian and Changhsingian stages of the Late Permian as well as the early Induan stage of the Early Triassic. It is the type genus of the family Owenettidae, and can be distinguished from other related taxa in that the posterior portion of the supratemporal bears a lateral notch and that the pineal foramen is surrounded by a depressed parietal surface on the skull table. Species The type species of ''Owenetta'' is ''O. rubidgei''. It is known from several skulls, but no postcranial skeleton. It was described in 1939 from a partial skull found from the Late Permian Cistecephalus Assemblage Zone of the Beaufort Group. Several other localities, all from the overlying Dicynodon Assemblage Zone, have yielded the remainder of the known ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lystrosaurus
''Lystrosaurus'' (; 'shovel lizard'; proper Greek is λίστρον ''lístron'' ‘tool for leveling or smoothing, shovel, spade, hoe’) is an extinct genus of herbivorous dicynodont therapsids from the late Permian and Early Triassic epochs (around 250 million years ago). It lived in what is now Antarctica, India, China, Mongolia, European Russia and South Africa. Four to six species are currently recognized, although from the 1930s to 1970s the number of species was thought to be much higher. They ranged in size from that of a small dog to 8 feet (2.5 meters) long. As a dicynodont, ''Lystrosaurus'' had only two teeth (a pair of tusk-like canines), and is thought to have had a horny beak that was used for biting off pieces of vegetation. ''Lystrosaurus'' was a heavily built, herbivorous animal, approximately the size of a pig. The structure of its shoulders and hip joints suggests that ''Lystrosaurus'' moved with a semi-sprawling gait. The forelimbs were even more robust than ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Synapsid
Synapsids + (, 'arch') > () "having a fused arch"; synonymous with ''theropsids'' (Greek, "beast-face") are one of the two major groups of animals that evolved from basal amniotes, the other being the sauropsids, the group that includes reptiles and birds. The group includes mammals and every animal more closely related to mammals than to sauropsids. Unlike other amniotes, synapsids have a single temporal fenestra, an opening low in the skull roof behind each eye orbit, leaving a bony arch beneath each; this accounts for their name. The distinctive temporal fenestra developed about 318 million years ago during the Late Carboniferous period, when synapsids and sauropsids diverged, but was subsequently merged with the orbit in early mammals. Traditionally, non-mammalian synapsids were believed to have evolved from reptiles, and therefore described as mammal-like reptiles in classical systematics, and primitive synapsids were also referred to as pelycosaurs, or pelycosaur-gr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pneumatostega
''Pneumatostega'' is an extinct genus of rhytidosteid temnospondyl from the early Triassic period of Cape Province of South Africa. It is known from the holotype BPI F981, a dorsal mould of a skull roof and from the referred specimen SAM 11188, partial skull fragments and postcranial remains recovered from the ''Lystrosaurus'' Assemblage Zone in the Beaufort Group near Middelburg. This genus was named by J. W. Cosgriff and J. M. Zawiskie in 1979 Events January * January 1 ** United Nations Secretary-General Kurt Waldheim heralds the start of the ''International Year of the Child''. Many musicians donate to the ''Music for UNICEF Concert'' fund, among them ABBA, who write the song ..., and the type species is ''Pneumatostega potamia''. References Triassic temnospondyls of Africa Early Triassic amphibians of Africa Triassic South Africa Fossils of South Africa Fossil taxa described in 1979 {{temnospondyli-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rhytidosteidae
Rhytidosteidae is a family of Temnospondyli that lived in the Permian and Triassic. Phylogeny Below is a cladogram from Dias-da-Silva and Marsicano (2011): References *Yates, AM (2000), A new tiny rhytidosteid (Temnospondyli: Stereospondyi) from the Early Triassic of Australia and the possibility of hidden temnospondyl diversity. J. Vert Paleontol. 20:484-489. External linksRhytidosteidae at Palaeos. Stereospondyls Permian temnospondyls Triassic temnospondyls Amphibian families Lopingian first appearances Early Triassic extinctions {{Temnospondyli-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Micropholis (amphibian)
''Micropholis'' (Greek mikros''' = small and '''pholis''' = scale) is an extinct genus of dissorophoid temnospondyl. Fossils have been found from the ''Lystrosaurus'' Assemblage Zone of the Karoo Basin in South Africa and are dated to the Induan (Early Triassic). Fossils have also been found from the lower Fremouw of Antarctica.''Micropholis'' is the only post-Permian dissorophoid and the only dissorophoid in what is presently the southern hemisphere and what would have been termed Gondwana during the amalgamation of Pangea. History of study ''Micropholis'' was one of the first dissorophoids to be named by English paleontologist Thomas Huxley in 1859 based on a partial skull. ''Micropholis stowii'' (properly ''Micropholis stowi'')'','' the type species, is named for George William Stow, the South African geologist and ethnologist who discovered the specimen and who proposed that it represented some extinct amphibian. English paleontologist Richard Owen later named a new genus a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dissorophoid
Dissorophoideans are a clade of medium-sized, temnospondyl amphibians that appeared during the Moscovian in Euramerica, and continued through to the Late Permian and the Early Triassic of Gondwana. They are distinguished by various details of the skull, and many forms seem to have been well adapted for life on land. Since 2008, Lissamphibia has been progressively widely considered part of this clade, but this position is still disputed by some authors. It is possible that the small Permo-Carboniferous Micromelerpetontidae and the large Late Permian Melosauridae may also belong in this clade. Phylogeny An extensive phylogenetic analysis of dissorophoids conducted in 2016 and 2018 found that the families Dissorophidae and Trematopidae are more closely related to each other than either is to the family Amphibamidae. Following a 2008 study, the Dissorophidae-Trematopidae clade was called Olsoniformes. Below is the cladogram from the 2018 analysis: References * Huttenlocker, Ad ... [...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] |
