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Dvinosaurus
''Dvinosaurus'' is an extinct genus of amphibious temnospondyls localized to regions of western and central Russia during the middle and late Permian, approximately 265-254 million years ago. Its discovery was first noted in 1921 by Russian paleontologist Vladimir Prokhorovich Amalitskii in a posthumously published paper that documents the findings of a site in Russia's Arkhangelsk District. Its name is derived from the proximity of this site to the Northern Dvina River. ''Dvinosaurus'' is thought to have been a gill-breathing, fully-aquatic tetrapod, characterized by a large, triangular head, short limbs, and a long powerful tail. A typical individual could grow to be approximately 40 in (100 cm) in length. Within this genus, the number of documented species has varied over the years since its discovery. Prior to his untimely death, Amalitskii described three species, ''Dvinosaurus primus, Dvinosaurus secundus,'' and ''Dvinosaurus tertius.'' Upon further analysis, however, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dvinosaurus Primus
''Dvinosaurus'' is an extinct genus of amphibious temnospondyls localized to regions of western and central Russia during the middle and late Permian, approximately 265-254 million years ago. Its discovery was first noted in 1921 by Russian paleontologist Vladimir Prokhorovich Amalitskii in a posthumously published paper that documents the findings of a site in Russia's Arkhangelsk District. Its name is derived from the proximity of this site to the Northern Dvina River. ''Dvinosaurus'' is thought to have been a gill-breathing, fully-aquatic tetrapod, characterized by a large, triangular head, short limbs, and a long powerful tail. A typical individual could grow to be approximately 40 in (100 cm) in length. Within this genus, the number of documented species has varied over the years since its discovery. Prior to his untimely death, Amalitskii described three species, ''Dvinosaurus primus, Dvinosaurus secundus,'' and ''Dvinosaurus tertius.'' Upon further analysis, however, t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Temnospondyli
Temnospondyli (from Greek τέμνειν, ''temnein'' 'to cut' and σπόνδυλος, ''spondylos'' 'vertebra') is a diverse order of small to giant tetrapods—often considered primitive amphibians—that flourished worldwide during the Carboniferous, Permian, and Triassic periods. A few species continued into the Jurassic and Cretaceous periods. Fossils have been found on every continent. During about 210 million years of evolutionary history, they adapted to a wide range of habitats, including freshwater, terrestrial, and even coastal marine environments. Their life history is well understood, with fossils known from the larval stage, metamorphosis, and maturity. Most temnospondyls were semiaquatic, although some were almost fully terrestrial, returning to the water only to breed. These temnospondyls were some of the first vertebrates fully adapted to life on land. Although temnospondyls are considered amphibians, many had characteristics, such as scales and armour-like bon ... [...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] |
Hybodontiformes
Hybodontiformes, commonly called hybodonts, are an extinct group of shark-like chondrichthyans, which existed from the late Devonian to the Late Cretaceous. They form the group of Elasmobranchii closest to neoselachians, the clade of modern sharks and rays. Hybodonts were named and are distinguished based on their conical tooth shape. They are also noted for the presence of a spine on each of their two dorsal fins. They were abundant in marine and freshwater environments during the late Paleozoic and early Mesozoic, but were rare in open marine environments by the end of the Jurassic, having been largely replaced by modern sharks, though they were still common in freshwater and marginal marine habitats. They survived until the end of the Cretaceous, before going extinct. Etymology The term hybodont comes from the Greek word ''ὕβος'' or ''ὑβός'' meaning hump or hump-backed and ''ὀδούς, ὀδοντ'' meaning tooth. This name was given based on their conical compres ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Batrachosuchus
''Batrachosuchus'' is a genus of temnospondyl amphibian that existed from the Early to Middle Triassic of Southern Africa (Ntawere Formation of Zambia and Burgersdorp Formation of South Africa) and the Blina Shale of Australia. Species Three species have been described: * '' Batrachosuchus browni'' * '' Batrachosuchus concordi'' * ''Batrachosuchus henwoodi ''Batrachosuchus henwoodi'' is a fossil species of amphibian, first described as ''Blinasaurus henwoodi'' by John W. Cosgriff in 1969. The species was placed in a new generic combination when separating the genus '' Blinasaurus'', currently subs ...'' References Further reading *''Wildlife of Gondwana: Dinosaurs and Other Vertebrates from the Ancient Supercontinent'' (Life of the Past) by Pat Vickers Rich, Thomas Hewitt Rich, Francesco Coffa, and Steven Morton Brachyopids Induan first appearances Olenekian life Anisian life Triassic temnospondyls of Africa Triassic South Africa Fossils of South Af ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bothriceps
''Bothriceps'' is an extinct genus of stereospondyl temnospondyl. It is a member of the infraorder Trematosauria and is the most basal brachyopomorph known. It is one of the only brachyopomorph that lies outside the superfamily Brachyopoidea, which includes the families Brachyopidae and Chigutisauridae. It shares several similarities to ''Keratobrachyops'', another basal brachyopomorph, and may be closely related to or even synonymous with it. The genus was named in 1859 by Thomas Henry Huxley with the description of its type species ''B. australis'' from the Early Triassic Upper Parmeener Group of Tasmania, Australia. It was originally assigned to the family Brachyopidae and was not reassigned to a more basal position until 2000, when the clade Brachyopomorpha was constructed to accommodate for it. The genus ''Bothriceps'' once included several species, but the only species assigned to it now is the type. ''Bothriceps major'', named in 1909, was reassigned to the family Rhytid ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Brachyopidae
Brachyopidae is an extinct scientific classification, family of temnospondyl Labyrinthodontia, labyrintodonts. They evolved in the early Mesozoic and were mostly aquatic. A fragmentary find from Lesotho, Africa is estimated to have been long, the largest amphibian ever known to have lived besides ''Prionosuchus''.Steyer, J.S. & Damiani, R. (2005): A giant brachyopoid temnospondyl from the Upper Triassic or Lower Jurassic of Lesotho. ''Bulletin de la Société Géologique de France'', no. 3: pp 243-248.abstract/ref> Brachyopids were the only group of temnospondyls to survive into the Jurassic aside from their sister family Chigutisauridae. With records of the family from the Jurassic of Asia. List of genera *''Banksiops'' *''Batrachosaurus'' *''Batrachosuchoides'' *''Batrachosuchus'' *''Brachyops'' *''Gobiops'' *''Notobrachyops'' *''Platycepsion'' *''Sinobrachyops'' *''Vanastega'' *''Xenobrachyops'' References External linksBrachyopidae at Palaeos. Brachyopids Amph ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Volga River
The Volga (; russian: Во́лга, a=Ru-Волга.ogg, p=ˈvoɫɡə) is the List of rivers of Europe#Rivers of Europe by length, longest river in Europe. Situated in Russia, it flows through Central Russia to Southern Russia and into the Caspian Sea. The Volga has a length of , and a catchment area of «Река Волга» , Russian State Water Registry which is more than twice the size of Ukraine. It is also Europe's largest river in terms of average discharge (hydrology), discharge at delta – between and – and of drainage basin. It is widely regarded as the Rivers in Russia, national river of Russia. The hypothetical old Russian state, the Rus' Khaganate, arose along the Volga . Historically, the river served as an important meeting place of various Eurasian civilizations. The river flows in Russia through forests, Fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Permian
The Permian ( ) is a geologic period and stratigraphic system which spans 47 million years from the end of the Carboniferous Period million years ago (Mya), to the beginning of the Triassic Period 251.9 Mya. It is the last period of the Paleozoic Era; the following Triassic Period belongs to the Mesozoic Era. The concept of the Permian was introduced in 1841 by geologist Sir Roderick Murchison, who named it after the region of Perm in Russia. The Permian witnessed the diversification of the two groups of amniotes, the synapsids and the sauropsids ( reptiles). The world at the time was dominated by the supercontinent Pangaea, which had formed due to the collision of Euramerica and Gondwana during the Carboniferous. Pangaea was surrounded by the superocean Panthalassa. The Carboniferous rainforest collapse left behind vast regions of desert within the continental interior. Amniotes, which could better cope with these drier conditions, rose to dominance in place of their am ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Neoteny
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 Monta ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
