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Hemipristis Serra Snaggettoth Shark Teeth 007
''Hemipristis'' (from el, ἡμι , 'half' and el, πρίστης 'saw') is a genus of weasel sharks, family Hemigaleidae. It contains one extant species, the snaggletooth shark (''H. elongata'') and several extinct species. ''Hemipristis'' has two distinct types of teeth in each section of its jaw. The ones on the upper jaw act as knives, cutting through the flesh of the prey, while the pointed ones on the bottom act as forks, spearing the prey and holding it down. Because this shark was poorly studied in the past and its top and bottom jaw teeth differ to such a great degree, its top and lower jaw teeth were assigned to a separate genus in the past. Species * ''Hemipristis elongata'' (Klunzinger, 1871) * †''Hemipristis curvatus'' * †''Hemipristis serra'' - An extinct species from the Oligocene-Miocene of Florida, South Carolina, and other areas on the Atlantic coast. See also * List of prehistoric cartilaginous fish This list of prehistoric cartilaginous fish genera i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Snaggletooth Shark
The snaggletooth shark, or fossil shark (''Hemipristis elongata''), is a species of weasel shark in the family Hemigaleidae, and the only extant member of the genus ''Hemipristis''. It is found in the Indo-West Pacific, including the Red Sea, from southeast Africa to the Philippines, north to China, and south to Australia, at depths from 1 to 130 metres. This shark can be found near the bottom of the water column of coastal areas, but can be found at continental and insular shelves. Its length is up to 240 cm (7.87 ft) . Despite being only vulnerable to extinction, this shark is very rarely seen. Anatomy The snaggletooth's coloration is light grey or bronze with no prominent markings. As its name suggests, it has sharp, serrated teeth on the upper jaw and hooked teeth on the bottom jaw. The shape of its body is fusiform, allowing it greater speed in the water. Reproduction is a special kind of viviparity, called placental viviparity, where the shark carries its live y ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Louis Agassiz
Jean Louis Rodolphe Agassiz ( ; ) FRS (For) FRSE (May 28, 1807 – December 14, 1873) was a Swiss-born American biologist and geologist who is recognized as a scholar of Earth's natural history. Spending his early life in Switzerland, he received a PhD at Erlangen and a medical degree in Munich. After studying with Georges Cuvier and Alexander von Humboldt in Paris, Agassiz was appointed professor of natural history at the University of Neuchâtel. He emigrated to the United States in 1847 after visiting Harvard University. He went on to become professor of zoology and geology at Harvard, to head its Lawrence Scientific School, and to found its Museum of Comparative Zoology. Agassiz is known for observational data gathering and analysis. He made institutional and scientific contributions to zoology, geology, and related areas, including multivolume research books running to thousands of pages. He is particularly known for his contributions to ichthyological classification, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hemipristis Elongata
The snaggletooth shark, or fossil shark (''Hemipristis elongata''), is a species of weasel shark in the family Hemigaleidae, and the only extant member of the genus ''Hemipristis''. It is found in the Indo-West Pacific, including the Red Sea, from southeast Africa to the Philippines, north to China, and south to Australia, at depths from 1 to 130 metres. This shark can be found near the bottom of the water column of coastal areas, but can be found at continental and insular shelves. Its length is up to 240 cm (7.87 ft) . Despite being only vulnerable to extinction, this shark is very rarely seen. Anatomy The snaggletooth's coloration is light grey or bronze with no prominent markings. As its name suggests, it has sharp, serrated teeth on the upper jaw and hooked teeth on the bottom jaw. The shape of its body is fusiform, allowing it greater speed in the water. Reproduction is a special kind of viviparity, called placental viviparity, where the shark carries its live y ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Genus
Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus comes above species and below family (taxonomy), family. In binomial nomenclature, the genus name forms the first part of the binomial species name for each species within the genus. :E.g. ''Panthera leo'' (lion) and ''Panthera onca'' (jaguar) are two species within the genus ''Panthera''. ''Panthera'' is a genus within the family Felidae. The composition of a genus is determined by taxonomy (biology), taxonomists. The standards for genus classification are not strictly codified, so different authorities often produce different classifications for genera. There are some general practices used, however, including the idea that a newly defined genus should fulfill these three criteria to be descriptively useful: # monophyly – all descendants ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Weasel Shark
The weasel sharks are a family, the Hemigaleidae, of ground sharks found from the eastern Atlantic Ocean to the continental Indo-Pacific. They are found in shallow coastal waters to a depth of . Most species are small, reaching no more than long, though the snaggletooth shark (''Hemipristis elongatus'') may reach . They have horizontally oval eyes, small spiracles, and precaudal pits. Two dorsal fins occur with the base of the first placed well forward of the pelvic fins. The caudal fin has a strong ventral lobe and undulations on the dorsal lobe margin. They feed on a variety of small bony fishes and invertebrates; at least two species specialize on cephalopods. They are not known to have attacked people. Genera and species The eight known species in this family are placed in four genera. ''Hemipristis'' is placed in the subfamily Hemipristinae, while ''Chaenogaleus'', ''Hemigaleus'', and ''Paragaleus'' are placed in the subfamily Hemigaleinae.Haaramo, M. (2005)Hemigaleidae - ... [...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] |
Hemigaleidae
The weasel sharks are a family, the Hemigaleidae, of ground sharks found from the eastern Atlantic Ocean to the continental Indo-Pacific. They are found in shallow coastal waters to a depth of . Most species are small, reaching no more than long, though the snaggletooth shark (''Hemipristis elongatus'') may reach . They have horizontally oval eyes, small spiracles, and precaudal pits. Two dorsal fins occur with the base of the first placed well forward of the pelvic fins. The caudal fin has a strong ventral lobe and undulations on the dorsal lobe margin. They feed on a variety of small bony fishes and invertebrates; at least two species specialize on cephalopods. They are not known to have attacked people. Genera and species The eight known species in this family are placed in four genera. ''Hemipristis'' is placed in the subfamily Hemipristinae, while ''Chaenogaleus'', ''Hemigaleus'', and ''Paragaleus'' are placed in the subfamily Hemigaleinae.Haaramo, M. (2005)Hemigalei ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Species
In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate sexes or mating types can produce fertile offspring, typically by sexual reproduction. Other ways of defining species include their karyotype, DNA sequence, morphology, behaviour or ecological niche. In addition, paleontologists use the concept of the chronospecies since fossil reproduction cannot be examined. The most recent rigorous estimate for the total number of species of eukaryotes is between 8 and 8.7 million. However, only about 14% of these had been described by 2011. All species (except viruses) are given a two-part name, a "binomial". The first part of a binomial is the genus to which the species belongs. The second part is called the specific name or the specific epithet (in botanical nomenclature, also sometimes i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Snaggletooth Shark
The snaggletooth shark, or fossil shark (''Hemipristis elongata''), is a species of weasel shark in the family Hemigaleidae, and the only extant member of the genus ''Hemipristis''. It is found in the Indo-West Pacific, including the Red Sea, from southeast Africa to the Philippines, north to China, and south to Australia, at depths from 1 to 130 metres. This shark can be found near the bottom of the water column of coastal areas, but can be found at continental and insular shelves. Its length is up to 240 cm (7.87 ft) . Despite being only vulnerable to extinction, this shark is very rarely seen. Anatomy The snaggletooth's coloration is light grey or bronze with no prominent markings. As its name suggests, it has sharp, serrated teeth on the upper jaw and hooked teeth on the bottom jaw. The shape of its body is fusiform, allowing it greater speed in the water. Reproduction is a special kind of viviparity, called placental viviparity, where the shark carries its live y ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hemipristis Curvatus
''Hemipristis curvatus'' is an extinct species of weasel shark which existed during the Eocene The Eocene ( ) Epoch is a geological epoch that lasted from about 56 to 33.9 million years ago (mya). It is the second epoch of the Paleogene Period in the modern Cenozoic Era. The name ''Eocene'' comes from the Ancient Greek (''ēṓs'', " ... epoch. It was described by Dames in 1883. References Hemipristis Eocene sharks Fossils of Poland Fossils of Mexico Fish described in 1879 {{Shark-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hemipristis Serra
''Hemipristis serra'' is an extinct species of weasel shark which existed during the Miocene epoch. It was described by Louis Agassiz in 1843. While today's snaggletooth shark is not very large or dangerous, ''Hemipristis serra'', which lived in the Atlantic Ocean during the Oligocene and Miocene, was considerably larger than its modern-day relative and had much larger teeth. Its total length is estimated to be . Marks made by the teeth of ''H. serra'' are often found on the bones of the manatee ''Metaxytherium'' leading some scientists to hypothesize that ''H. serra'' specialized in preying on these sirenians. In the Gatun Formation of Panama, ''H. serra'' was contemporary with pups of the large lamniform shark ''Otodus megalodon'', and both it and the great hammerhead The great hammerhead (''Sphyrna mokarran'') or great hammerhead shark is the largest species of hammerhead shark, belonging to the family Sphyrnidae, attaining an average length of and reaching a maximum le ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Prehistoric Cartilaginous Fish
This list of prehistoric cartilaginous fish genera is an attempt to create a comprehensive listing of all genera that have ever been included in the class chondrichthyes ''and'' are known from the fossil record. This list excludes purely vernacular terms, genera that are now considered invalid, doubtful (nomina dubia), or were not formally published (nomina nuda), as well as junior synonyms of more established names, and genera that are no longer considered to be cartilaginous fish. It includes all commonly accepted genera. This list currently contains 804 generic names. * Extinct genera are marked by a dagger ( †). * Extant taxon genera are bolded. Naming conventions and terminology Naming conventions and terminology follow the International Code of Zoological Nomenclature. Technical terms used include: * Junior synonym: A name which describes the same taxon as a previously published name. If two or more genera are formally designated and the type specimens are later assigne ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
