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Ostracod
Ostracods, or ostracodes, are a class of the Crustacea (class Ostracoda), sometimes known as seed shrimp. Some 70,000 species (only 13,000 of which are extant) have been identified, grouped into several orders. They are small crustaceans, typically around in size, but varying from in the case of '' Gigantocypris''. Their bodies are flattened from side to side and protected by a bivalve-like, chitinous or calcareous valve or "shell". The hinge of the two valves is in the upper (dorsal) region of the body. Ostracods are grouped together based on gross morphology. While early work indicated the group may not be monophyletic and early molecular phylogeny was ambiguous on this front, recent combined analyses of molecular and morphological data found support for monophyly in analyses with broadest taxon sampling. Ecologically, marine ostracods can be part of the zooplankton or (most commonly) are part of the benthos, living on or inside the upper layer of the sea floor. While ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gigantocypris
The giant ostracod (''Gigantocypris'') or the giant seed shrimp is a genus of ostracod crustaceans in family Cypridinidae, and among the most well-known members of the class Ostracoda (together with '' Vargula hilgendorfii''). Its members are extremely large for ostracods, measuring up to across, have a globular shape, are typically semi-transparent orange or reddish, and while compound eyes are absent they have a large pair of mirror-like naupliar eyes that are used to locate their small animal prey. They are found worldwide in dark, deep and cold oceans. Range and habitat ''Gigantocypris'' are ubiquitous in open oceans around the world, ranging from tropical to polar regions. Although locally abundant, the distributions of the individual species are often not well known. ''G. dracontovalis'' is found worldwide, mostly deeper than the other species. ''G. agassizii'' is essentially a widespread Pacific species, and ''G. muelleri'' a widespread Atlantic and Southern Ocean spec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cyprididae
Cyprididae is "the most diverse group of freshwater ostracods". It contains over 1000 species, which represents 50% of the known species of freshwater ostracods (other speciose families include Candonidae, with 25%, and Limnocytheridae, with 10%). Around 60% of genera in the family are endemic to a single zoogeographic region. The family contains 16 subfamilies, and is most diverse in the Afrotropical realm, with over 300 species in 45 genera. Many Cyprididae occur in temporary water bodies and have drought-resistant eggs, mixed/parthenogenetic reproduction and ability to swim. These biological attributes pre-adapt them to form successful radiations in these habitats. '' Bennelongia'' is an interesting of the family Cyprididae. It may be the last true descendant of the Mesozoic (and now extinct) lineage of '' Cypridea'', which was a dominant lineage of ostracod in non-marine waters in the Cretaceous. Taxonomy The following genera are recognised in the family Cyprididae: * ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Crustacean
Crustaceans (Crustacea, ) form a large, diverse arthropod taxon which includes such animals as decapods, seed shrimp, branchiopods, fish lice, krill, remipedes, isopods, barnacles, copepods, amphipods and mantis shrimp. The crustacean group can be treated as a subphylum under the clade Mandibulata. It is now well accepted that the hexapods emerged deep in the Crustacean group, with the completed group referred to as Pancrustacea. Some crustaceans ( Remipedia, Cephalocarida, Branchiopoda) are more closely related to insects and the other hexapods than they are to certain other crustaceans. The 67,000 described species range in size from '' Stygotantulus stocki'' at , to the Japanese spider crab with a leg span of up to and a mass of . Like other arthropods, crustaceans have an exoskeleton, which they moult to grow. They are distinguished from other groups of arthropods, such as insects, myriapods and chelicerates, by the possession of biramous (two-parted) limbs, and by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Myodocopida
The Myodocopida is one of the two orders within the Myodocopa, in turn a subclass of the Ostracoda. The Myodocopida are distinguished by a worm-like seventh limb, and, usually, a rostrum above an incisure (notch) from which the antennae can protrude. Unlike other ostracods, many species of the Myodocopida have lateral compound eyes Over the last thirty years there has been much research into the morphology, behaviour and distribution of myodocopids. More recently, DNA sequences have been used to investigate the phylogeny A phylogenetic tree (also phylogeny or evolutionary tree Felsenstein J. (2004). ''Inferring Phylogenies'' Sinauer Associates: Sunderland, MA.) is a branching diagram or a tree showing the evolutionary relationships among various biological s ... of various groups. References External links * Crustacean orders Taxa named by Georg Ossian Sars {{Ostracod-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Halocyprida
The Halocyprida is one of the two orders within the Myodocopa, in turn a subclass of the ostracod Ostracods, or ostracodes, are a class of the Crustacea (class Ostracoda), sometimes known as seed shrimp. Some 70,000 species (only 13,000 of which are extant) have been identified, grouped into several orders. They are small crustaceans, typic ...s. Like their relatives in the order Myodocopida, they have a long exopod on the second antenna. However, unlike myodocopids, their fifth appendage is leg-like rather than modified for feeding, their seventh limb is reduced or absent, and they have no lateral eyes. The group is primarily planktonic. There are two suborders: Halocypridina and Cladocopina. References External linksAn Atlas of Southern Ocean Planktonic Ostracods Crustacean orders {{ostracod-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Podocopa
The Podocopa are a subclass of ostracods. Members of the subclass Podocopa can be differentiated from the other subclass of ostracods ( Myodocopa) by the morphology of the second antenna Antenna ( antennas or antennae) may refer to: Science and engineering * Antenna (radio), also known as an aerial, a transducer designed to transmit or receive electromagnetic (e.g., TV or radio) waves * Antennae Galaxies, the name of two collid ...: the Podocopa have a relatively long endopod, whereas the Myodocopa have a relatively long exopod. The seventh limb of the Podocopa has a variety of forms or is absent, but is never an annulated worm-like limb (as seen in some Myodocopa). Taxonomy The following orders and unplaced families are recognised in the subclass Podocopa: * Order Palaeocopida * Order Platycopida * Order Podocopida * Unplaced families ** Family † Pachydomellidae Berdan & Sohn, 1961 ** Family † Rectellidae Neckaya, 1966 ** Family † Rectonariidae Gruendel, 1962 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Platycopida
The Podocopa are a subclass of ostracods. Members of the subclass Podocopa can be differentiated from the other subclass of ostracods (Myodocopa Traditionally, the Myodocopa and Podocopa have been classified as subclasses within the class Ostracoda, although there is some question about how closely related the two groups actually are. The Myodocopa are defined by possession of a poorly ca ...) by the morphology of the second antenna: the Podocopa have a relatively long endopod, whereas the Myodocopa have a relatively long exopod. The seventh limb of the Podocopa has a variety of forms or is absent, but is never an annulated worm-like limb (as seen in some Myodocopa). Taxonomy The following orders and unplaced families are recognised in the subclass Podocopa: * Order Palaeocopida * Order Platycopida * Order Podocopida * Unplaced families ** Family † Pachydomellidae Berdan & Sohn, 1961 ** Family † Rectellidae Neckaya, 1966 ** Family † Rectonariidae Gruendel, 1962 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Podocopida
The Podocopida are an order of ostracods in the subclass Podocopa. It is the most diverse of the four orders of ostracods, and also has a rich fossil record A fossil (from Classical Latin , ) is any preserved remains, impression, or trace of any once-living thing from a past geological age. Examples include bones, shells, exoskeletons, stone imprints of animals or microbes, objects preserved .... Taxonomy The following suborders and unassigned taxa are contained in the order Podocopida: *Superfamily † Carbonitacea *Suborder Bairdiocopina *Suborder Cypridocopina *Suborder Cytherocopina *Suborder Darwinulocopina *Suborder Sigilliocopina See also * Cyprididae References Podocopida Crustacean orders {{ostracod-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Myodocopa
Traditionally, the Myodocopa and Podocopa have been classified as subclasses within the class Ostracoda, although there is some question about how closely related the two groups actually are. The Myodocopa are defined by possession of a poorly calcified carapace, and 8–9 articles in the exopod of the second antenna. The ventral margin of the carapace is not concave, and the valves do not overlap to a great extent. Although the carapace of myodocopans is poorly calcified, some fossils are known for the group. (In contrast, thousands of fossil species are named for the Podocopa). Of particular interest are those fossils for which the internal body parts (and not just the carapace) are preserved. This provides a lot more information about the likely relatives to the fossil taxa, including relatives still alive today. Two recent fossils of much interest have been found from Silurian The Silurian ( ) is a geologic period and system spanning 24.6 million years from the end of th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Palaeocopida
Palaeocopida is an order of ostracods in the subclass Podocopa. Most species in the suborder are extinct, and only the genera ''Manawa Manawa can refer to: *Manawa, Wisconsin, a city in Wisconsin * ''Manawa'' (crustacean): ''Manawa'' Hornibrook, 1949, a genus of ostracod *''Manawa'' Forster, 1970 an invalid genus of spider: now '' Mesudus'' Özdikmen, 2007 *''Manawa'' Bergquist & F ...'' and '' Puncia'' in the family Punciidae are extant. Taxonomy The following suborders are recognised in the order Palaeocopida: * † Beyrichicopina * † Binodicopina * † Eridostracina * Kirkbyocopina * † Nodellocopina * † Palaeocopina References * Palaeocopida (Ostracoda) across the Permian–Triassic events: new data from southwestern Taurus (Turkey). Crasquin-Soleau S., Marcoux J., Angiolini L. and Nicora A., 2004, Journal of micropalaeontology, 23(1), pages 67–76, {{Taxonbar, from=Q15611315 Crustacean orders Podocopa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ordovician
The Ordovician ( ) is a geologic period and system, the second of six periods of the Paleozoic Era. The Ordovician spans 41.6 million years from the end of the Cambrian Period million years ago (Mya) to the start of the Silurian Period Mya. The Ordovician, named after the Welsh tribe of the Ordovices, was defined by Charles Lapworth in 1879 to resolve a dispute between followers of Adam Sedgwick and Roderick Murchison, who were placing the same rock beds in North Wales in the Cambrian and Silurian systems, respectively. Lapworth recognized that the fossil fauna in the disputed strata were different from those of either the Cambrian or the Silurian systems, and placed them in a system of their own. The Ordovician received international approval in 1960 (forty years after Lapworth's death), when it was adopted as an official period of the Paleozoic Era by the International Geological Congress. Life continued to flourish during the Ordovician as it did in the earlier Cambrian P ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Benthos
Benthos (), also known as benthon, is the community of organisms that live on, in, or near the bottom of a sea, river, lake, or stream, also known as the benthic zone.Benthos from the Census of Antarctic Marine Life website This community lives in or near marine or freshwater sedimentary environments, from tidal pools along the , out to the continental shelf, and then down to the [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
