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Jenynsia Multidentata
''Jenynsia multidentata'' is a species of killifish from the Family (biology), family Anablepidae. It is a Viviparity, viviparous, Demersal fish, benthopelagic species in the genus Onesided livebearer, ''Jenynsia''. They are onesided livebearers with a clear asymmetry of the males' genitalia. With onset of maturity, the anal fin of male fish develops into a gonopodium which can be brought forward on one side only. Based on the bending to the left or to the right of the tip of the gonopodium, two morphs of male fish can be distinguished. Taxonomy The species ''Jenynsia multidentata'' was originally described in 1842 as ''Lebias multidentata'' by the naturalist Leonard Jenyns. Accepted synonyms are ''Fitzroyia multidentata'' also described by Jenyns in 1842 and ''Poecilia punctata'' which was suggested by Valenciennes in 1846. Geographical distribution ''Jenynsia multidentata'' is the most widespread species of the genus Onesided livebearer, ''Jenynsia''. The distribution is r ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Leonard Jenyns
Leonard Jenyns (25 May 1800 – 1 September 1893) was an English clergyman, author and naturalist. He was forced to take on the name Leonard Blomefield to receive an inheritance. He is chiefly remembered for his detailed phenology observations of the times of year at which events in natural history occurred. Personal life Jenyns was born in 1800 at No. 85 Pall Mall, London, the home of his maternal grandfather. He was the youngest son of George Leonard Jenyns of Bottisham Hall, Cambridgeshire, a magistrate, landowner and a prebendary of Ely Cathedral. His mother Mary (1763–1832) was the daughter of Dr. William Heberden (1710–1801). His father had inherited the Bottisham Hall property on the death of his distant cousin Soame Jenyns (1704–1787). By 1812, Jenyns began to study natural history encouraged by his great uncle. He went to Eton in 1813 where he read, and was inspired by Gilbert White's ''Natural History of Selborne''. In 1817 Jenyns was introduced to Sir ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Achille Valenciennes
Achille Valenciennes (9 August 1794 – 13 April 1865) was a French zoologist. Valenciennes was born in Paris, and studied under Georges Cuvier. His study of parasitic worms in humans made an important contribution to the study of parasitology. He also carried out diverse systematic classifications, linking fossil and current species. He worked with Cuvier on the 22-volume "'' Histoire Naturelle des Poissons''" (Natural History of Fish) (1828–1848), carrying on alone after Cuvier died in 1832. In 1832, he succeeded Henri Marie Ducrotay de Blainville (1777–1850) as chair of ''Histoire naturelle des mollusques, des vers et des zoophytes'' at the Muséum national d'histoire naturelle. Early in his career, he was given the task of classifying animals described by Alexander von Humboldt (1769–1859) during his travels in the American tropics (1799 to 1803), and a lasting friendship was established between the two men. He is the binomial authority for many species of fish, s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Killifish
A killifish is any of various oviparous (egg-laying) cyprinodontiform fish (including families Aplocheilidae, Cyprinodontidae, Fundulidae, Profundulidae and Valenciidae). All together, there are 1,270 species of killifish, the biggest family being Rivulidae, containing more than 320 species. As an adaptation to living in ephemeral waters, the eggs of most killifish can survive periods of partial dehydration. Many of the species rely on such a diapause, since the eggs would not survive more than a few weeks if entirely submerged in water. The adults of some species, such as '' Kryptolebias marmoratus'', can additionally survive out of the water for several weeks. Most killies are small fish, from , with the largest species growing to just under . The word ''killifish'' is of uncertain origin, but is likely to have come from the Dutch ''kil'' for a kill (small stream). Although ''killifish'' is sometimes used as an English equivalent to the taxonomical term ''Cyprinodont ... [...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 opi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anablepidae
Anablepidae is a family of fishes which live in brackish and freshwater habitats from southern Mexico to southern South America. There are three genera with sixteen species: the four-eyed fishes (genus '' Anableps''), the onesided livebearers (genus '' Jenynsia'') and the white-eye, ''Oxyzygonectes dovii''. Fish of this family eat mostly insects and other invertebrates. Reproduction Fish in the subfamily Oxyzygonectinae are ovoviviparous. The Anablepinae are livebearers. They mate on one side only, right-"handed" males with left-"handed" females and vice versa. The male has specialized anal rays which are greatly elongated and fused into a tube called a gonopodium associated with the sperm duct which he uses as an intromittent organ An intromittent organ is any external organ of a male organism that is specialized to deliver sperm during copulation. Intromittent organs are found most often in terrestrial species, as most non-mammalian aquatic species fertilize their eggs ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Viviparity
Among animals, viviparity is development of the embryo inside the body of the parent. This is opposed to oviparity which is a reproductive mode in which females lay developing eggs that complete their development and hatch externally from the mother. The term 'viviparity' and its adjective form 'viviparous' derive from the Latin ''vivus'' meaning "living" and ''pario'' meaning "give birth to". Reproductive mode Five modes of reproduction have been differentiated in animals based on relations between zygote and parents. The five include two nonviviparous modes: ovuliparity, with external fertilisation, and oviparity, with internal fertilisation. In the latter, the female lays zygotes as eggs with a large yolk; this occurs in all birds, most reptiles, and some fishes. These modes are distinguished from viviparity, which covers all the modes that result in live birth: *Histotrophic viviparity: the zygotes develop in the female's oviducts, but find their nutrients by oophagy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Demersal Fish
Demersal fish, also known as groundfish, live and feed on or near the bottom of seas or lakes (the demersal zone).Walrond Carl . "Coastal fish - Fish of the open sea floor"Te Ara - the Encyclopedia of New Zealand. Updated 2 March 2009 They occupy the sea floors and lake beds, which usually consist of mud, sand, gravel or rocks. In coastal waters they are found on or near the continental shelf, and in deep waters they are found on or near the continental slope or along the continental rise. They are not generally found in the deepest waters, such as abyssal depths or on the abyssal plain, but they can be found around seamounts and islands. The word ''demersal'' comes from the Latin ''demergere'', which means ''to sink''. Demersal fish are bottom feeders. They can be contrasted with pelagic fish which live and feed away from the bottom in the open water column. Demersal fish fillets contain little fish oil (one to four percent), whereas pelagic fish can contain up to 30 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Onesided Livebearer
''Jenynsia'' is a genus of freshwater fishes in the family Anablepidae. Like '' Anableps'' species, they are onesided livebearers: some sources indicate that they only mate on one side, right-"handed" males with left-"handed" females and vice versa. However other sources dispute this. These South American fish are viviparous. Distribution Species of the genus are distributed in the Río de la Plata Basin and Atlantic coastal drainages from Río Negro Province, Argentina, to the city of Rio de Janeiro, Brazil, and in the Andean drainages of northwest Argentina and southern Bolivia. Taxonomy ''Jenynsia'' is the sister group to the genus '' Anableps'' and both are classified in the subfamily Anablepinae; together with the genus ''Oxyzygonectes'' they compose the family Anablepidae. ''Jenynsia'' contains two subgenera. Members of the subgenus ''Plesiojenysia'' Ghedotti, 1998, are distributed in the uplands of southern Brazil. Members of the subgenus ''Jenynsia'' are mor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
