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Xenacanthida
Xenacanthida (or Xenacanthiforms) is a super-order of extinct shark-like elasmobranchs that appeared during the Lower Carboniferous period. The order includes the families Xenacanthidae, Sphenacanthidae, Diplodoselachidae, and Orthacanthidae. The most notable members of the group are the genera ''Xenacanthus'' and ''Orthacanthus''. Some xenacanths may have grown to lengths of .Beck, Kimberley G.; oler-Gijón, Rodrigo; Carlucci, Jesse R.; Willis, Ray E. (December 2014). "Morphology and Histology of Dorsal Spines of the Xenacanthid Shark Orthacanthus platypternus from the Lower Permian of Texas, USA: Palaeobiological and Palaeoenvironmental Implications". ''Acta Palaeontologica Polonica''. 61 (1): 97–117. doi:10.4202/app.00126.2014 Most forms had large serrated spines extending backwards from the neck. ''Xenacanthus'' had characteristic teeth. Most xenacanths died out at the end of the Permian in the Permian Mass Extinction, with only a few forms surviving into the Triassic peri ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Xenacanthidae
Xenacanthidae is a family of prehistoric sharks in the order Xenacanthida Xenacanthida (or Xenacanthiforms) is a super-order of extinct shark-like elasmobranchs that appeared during the Lower Carboniferous period. The order includes the families Xenacanthidae, Sphenacanthidae, Diplodoselachidae, and Orthacanthidae. Th ....Ginter, M., Hampe, O., Duffin, C., 2010.Handbook of Paleoichthyology Volume 3D: Chondrichthyes: Paleozoic Elasmobranchii: Teeth. ''in'' Schultze, H. (ed.) Handbook of Paleoichthyology. Verlag Dr. Friedrich Pfeil, München References Carboniferous sharks Permian sharks Triassic sharks Prehistoric cartilaginous fish families Carboniferous first appearances Triassic extinctions {{paleo-shark-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Barbclabornia
''Barbclabornia'' is an extinct genus of xenacanthid shark from the Early Permian and possibly upper Pennsylvanian of North America. The genus contains a single described species: ''B. luedersensis''. It has been found in several places within Asselian and Atinskian formations, including the Clear Fork, Albany, Wichita, and Dunkard Groups. There are possible examples from the Gzhelian-aged Admire, Monongahela, and Conemaugh groups.Johnson, G. (2003). Dentitions of Barbclabornia (new genus, Chondrichthyes: Xenacanthiformes) from the Upper Palaeozoic of North America. ''Fossil Record, 6'', 125-146. Discovery ''Barbclabornia'' was initially only known from isolated teeth, which were assigned to the genus ''Xenacanthus'' in 1970 based on the belief that all Upper Paleozoic xenacanthids belonged to said genus. In 2003, ''X. luedersensis'' would be reassigned to a new genus after differences in tooth structure were described, and with the discovery of a large palatoquadrate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Shark
Sharks are a group of elasmobranch fish characterized by a cartilaginous skeleton, five to seven gill slits on the sides of the head, and pectoral fins that are not fused to the head. Modern sharks are classified within the clade Selachimorpha (or Selachii) and are the sister group to the rays. However, the term "shark" has also been used to refer to all extinct members of Chondrichthyes with a shark-like morphology, such as hybodonts and xenacanths. The oldest modern sharks are known from the Early Jurassic. They range in size from the small dwarf lanternshark (''Etmopterus perryi''), a deep sea species that is only in length, to the whale shark (''Rhincodon typus''), the largest fish in the world, which reaches approximately in length. Sharks are found in all seas and are common to depths up to . They generally do not live in freshwater, although there are a few known exceptions, such as the bull shark and the river shark, which can be found in both seawater and fresh ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Plicatodus
''Plicatodus'' is a prehistoric shark in the family Xenacanthidae that lived in Europe during the late Carboniferous and Early Permian Periods. It was described by Oliver Hampe in 1995, and the type species is ''Plicatodus jordani''. The type locality for this genus is the Saar-Nahe basin.Plicatodus jordani n. g., n. sp., a new xenacanthid shark from the Lower Permian of Europe (Saar-Nahe Basin, Germany) by Oliver Hampe, 1995. Description ''Plicatodus'' fossils generally on ...[...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Orthacanthus
''Orthacanthus'' is an extinct genus of fresh-water xenacanthid sharks, named by Louis Agassiz in 1836, ranging from the Upper Carboniferous until the Lower Permian. ''Orthacanthus'' had a nektobenthic life habitat, with a carnivorous diet. Multiple sources have also discovered evidence of cannibalism in the diet of ''Orthacanthus'' and of "filial cannibalism" where adult ''Orthacanthus'' preyed upon juvenile ''Orthacanthus.'' The genus ''Orthacanthus'' has been synonymized with ''Dittodus'' (Owen, 1867), ''Didymodus'' (Cope, 1883), and ''Diplodus'' (Agassiz, 1843). About 260 million years ago, ''Orthacanthus'' was the apex predator of freshwater swamps and bayous in Europe and North America. Mature ''Orthacanthus'' reached nearly 3 meters (10 feet) in length. ''Orthacanthus'' teeth have a minimum of three cusps, two principal cusps, and an intermediate cusp, where the principal cusps are variously serrated, with complex base morphology. Additionally, ''Orthacanthus'' can be dia ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lebachacanthus
''Lebachacanthus'' is a genus of extinct Xenacanthid shark known from the early Permian. During the late Paleozoic, xenacanths ruled the freshwater swamps and bogs of the world, preying on small amphibian-like animals. Paleobiology ''Lebachacanthus'' patrolled both fresh and marine waters, possibly preying on larvae of the temnospondyli and Acanthodians. The genus displays sexually dimorphic features; females had longer fin spines than males. Histological and biometric analyses of the spines of specimens provides information on the development and age at death of the fish and the environmental conditions in which they lived. Description Like most other xenacanthids, this genus possessed an array of spines arising from the dorsal fins. It grew up to . The genus is often confused with the similar genus ''Orthacanthus''; the two genera belong to entirely separate families. The teeth of this shark were multi-cusped, with the central cusp flanked by two sharp accessory "tines" on ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Diplodoselachidae
Diplodoselachidae is a family of extinct xenacanthid sharks that ranged from the Permian to mid Triassic The Triassic ( ) is a geologic period and system which spans 50.6 million years from the end of the Permian Period 251.902 million years ago ( Mya), to the beginning of the Jurassic Period 201.36 Mya. The Triassic is the first and shortest period .... References {{Taxonbar, from=Q21220816 Prehistoric sharks Prehistoric cartilaginous fish families ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bransonella
''Bransonella'' is an extinct genus of marine Xenacanth shark which lived during the Paleozoic era. It is known only from teeth which are easily distinguished from related genera by ornamentation on the cusp shaped like an inverted "V" and fin spines Teeth attributed to this genus are small, no greater than 2 millimeters. This suggests a small body size likely not exceeding a meter in length. It has been suggested their lifestyle was similar to modern Catsharks. It was used to erect a new order along with ''Barbclabornia'' based on ornamentation. There are four species currently attributed to this genus. The first species described was ''B. tridentata'' in 1933, which was erroneously identified as a conodont. ''B. nebraskensis'' was described from the late Pennsylvanian of Nebraska and later recognized from the middle Mississippian to the early Permian of Kansas, the Urals, Poland, Belgium, Russia, and England. ''B. lingulata'' is known from Serpukhovian of Russia. ''B. tribul ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Xenacanthus
''Xenacanthus'' (from Ancient Greek ξένος, xénos, 'foreign, alien' + ἄκανθος, akanthos, 'spine') is a genus of prehistoric sharks. The first species of the genus lived in the later Devonian period, and they survived until the end of the Triassic, 202 million years ago. Fossils of various species have been found worldwide. Description ''Xenacanthus'' had a number of features that distinguished it from modern sharks. This freshwater shark was usually about one meter (3.3 feet) in length, and never longer than . The dorsal fin was ribbonlike and ran the entire length of the back and round the tail, where it joined with the anal fin. This arrangement resembles that of modern conger eels, and ''Xenacanthus'' probably swam in a similar manner. A distinctive spine projected from the back of the head and gave the genus its name. The spike has even been speculated to have been venomous, perhaps in a similar manner to a sting ray. This is quite plausible as the rays are clo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carboniferous
The Carboniferous ( ) is a geologic period and system of the Paleozoic that spans 60 million years from the end of the Devonian Period million years ago ( Mya), to the beginning of the Permian Period, million years ago. The name ''Carboniferous'' means "coal-bearing", from the Latin '' carbō'' ("coal") and '' ferō'' ("bear, carry"), and refers to the many coal beds formed globally during that time. The first of the modern 'system' names, it was coined by geologists William Conybeare and William Phillips in 1822, based on a study of the British rock succession. The Carboniferous is often treated in North America as two geological periods, the earlier Mississippian and the later Pennsylvanian. Terrestrial animal life was well established by the Carboniferous Period. Tetrapods (four limbed vertebrates), which had originated from lobe-finned fish during the preceding Devonian, became pentadactylous in and diversified during the Carboniferous, including early amphibian line ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Triodus
''Triodus'' is an extinct genus of xenacanthidan shark that lived from the Carboniferous to the Triassic. It was a freshwater shark, and fossils have been found in the Chinle Formation and Black Prince Limestone of Arizona, the Petrified Forest Member of New Mexico and the Tecovas Formation of Texas, United States.''Triodus'' at .org In 2017, a new species ''Triodus richterae'' was described from the of Brazil
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