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Anablepidae
Anablepidae is a family of ray-finned 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 fertiliz ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Onesided Livebearer
''Jenynsia'' is a genus of fresh water, freshwater fishes in the family (biology), 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 viviparity, 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 Andes, Andean drainages of northwest Argentina and southern Bolivia. Taxonomy ''Jenynsia'' is the cladistics, 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 ''Plesiojenynsia'' Ghedotti, 1998, are distributed in the uplands of southern Bra ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Anablepidae
Anablepidae is a family of ray-finned 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 fertiliz ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Four-eyed Fish
The four-eyed fishes are a genus, ''Anableps'', of fishes in the family Anablepidae. They have eyes raised above the top of the head and divided in two different parts, so that they can see below and above the water surface at the same time. The optomotor response or OMR has been used as a test to investigate potential differential visual processing in Anableps on normal versus ‘blinded’ fish (the eyes are actually covered—not physically blinded). It was found that the OMR does exist in Anableps and that the strength of this response is dependent on the visual field being tested—a stronger OMR was seen as a result of visual stimulation from the aerial environment. Like their relatives, the onesided livebearers, four-eyed fishes mate only on one side, right-"handed" males with left-"handed" females and vice versa. These fish inhabit fresh and brackish water and are only rarely coastal marine. They originate in lowlands in southern Mexico to Honduras and northern South A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
White-eye (fish)
The white-eye (''Oxyzygonectes dovii'') is a species of killifish of the family (biology), family Anablepidae. This species is the only member of its genus, ''Oxyzygonectes'', and the subfamily Oxyzygonectinae. This fish species is found in Pacific drainages in Nicaragua, Costa Rica, and Panama. ''O. dovii'' has no gonopodium like the other members of its family. The dorsal and anal fins are posteriorly placed just before the caudal peduncle and well behind the midbody. The reach a maximum length of about 15 centimetres (6 in) fish measurement, TL. Many of these fish inhabit brackish waters. They are found in rivers of low elevation, up to 15 metres (50 ft) above sea level. These fish feed on detritus, algae, and sometimes on terrestrial insects. Though it occurs in estuaries, it breeds in freshwater. This species is not a seasonal killifish. ''O. dovii'' has been bred in captivity. Etymology The fish is named in honor of John Melmoth Dow (1827–1892), of t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Oxyzygonectes
The white-eye (''Oxyzygonectes dovii'') is a species of killifish of the family Anablepidae. This species is the only member of its genus, ''Oxyzygonectes'', and the subfamily Oxyzygonectinae. This fish species is found in Pacific drainages in Nicaragua, Costa Rica, and Panama. ''O. dovii'' has no gonopodium like the other members of its family. The dorsal and anal fins are posteriorly placed just before the caudal peduncle and well behind the midbody. The reach a maximum length of about 15 centimetres (6 in) TL. Many of these fish inhabit brackish waters. They are found in rivers of low elevation, up to 15 metres (50 ft) above sea level Mean sea level (MSL, often shortened to sea level) is an mean, average surface level of one or more among Earth's coastal Body of water, bodies of water from which heights such as elevation may be measured. The global MSL is a type of vertical .... These fish feed on detritus, algae, and sometimes on terrestrial insects ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gonopodium
Fins are moving appendages protruding from the body of fish that interact with water to generate thrust and help the fish aquatic locomotion, swim. Apart from the tail or caudal fin, fish fins have no direct connection with the vertebral column, back bone and are supported only by muscles. Fish fins are distinctive anatomical features with varying structures among different clades: in ray-finned fish (Actinopterygii), fins are mainly composed of bone, bony spine (zoology), spines or ray (fish fin anatomy), rays covered by a thin stretch of fish scale, scaleless skin; in lobe-finned fish (Sarcopterygii) such as coelacanths and lungfish, fins are short rays based around a muscular central limb bud, bud supported by appendicular skeleton, jointed bones; in cartilaginous fish (Chondrichthyes) and jawless fish (Agnatha), fins are fleshy "flipper (anatomy), flippers" supported by a cartilaginous skeleton. Fins at different locations of the fish body serve different purposes, and are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Penis
A penis (; : penises or penes) is a sex organ through which male and hermaphrodite animals expel semen during copulation (zoology), copulation, and through which male placental mammals and marsupials also Urination, urinate. The term ''penis'' applies to many intromittent organs of vertebrates and invertebrates, but not to all. As an example, the intromittent organ of most Cephalopoda is the hectocotylus, a specialized arm, and male spiders use their pedipalps. Even within the Vertebrata, there are morphological variants with specific terminology, such as Hemipenis, hemipenes. Etymology The word "penis" is taken from the Latin word for "Latin profanity#Synonyms and metaphors, tail". Some derive that from Proto-Indo-European language, Indo-European ''*pesnis'', and the Greek word πέος = "penis" from Indo-European ''*pesos''. Prior to the adoption of the Latin word in English, the penis was referred to as a "yard". The Oxford English Dictionary cites an example of the w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Freshwater Fish Of Mexico
Fresh water or freshwater is any naturally occurring liquid or frozen water containing low concentrations of dissolved salts and other total dissolved solids. The term excludes seawater and brackish water, but it does include non-salty mineral-rich waters, such as chalybeate springs. Fresh water may encompass frozen and meltwater in ice sheets, ice caps, glaciers, snowfields and icebergs, natural precipitations such as rainfall, snowfall, hail/ sleet and graupel, and surface runoffs that form inland bodies of water such as wetlands, ponds, lakes, rivers, streams, as well as groundwater contained in aquifers, subterranean rivers and lakes. Water is critical to the survival of all living organisms. Many organisms can thrive on salt water, but the great majority of vascular plants and most insects, amphibians, reptiles, mammals and birds need fresh water to survive. Fresh water is the water resource that is of the most and immediate use to humans. Fresh water is not alway ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Freshwater Fish Of South America
Fresh water or freshwater is any naturally occurring liquid or frozen water containing low concentrations of dissolved salts and other total dissolved solids. The term excludes seawater and brackish water, but it does include non-salty mineral-rich waters, such as chalybeate springs. Fresh water may encompass frozen and meltwater in ice sheets, ice caps, glaciers, snowfields and icebergs, natural precipitations such as rainfall, snowfall, hail/ sleet and graupel, and surface runoffs that form inland bodies of water such as wetlands, ponds, lakes, rivers, streams, as well as groundwater contained in aquifers, subterranean rivers and lakes. Water is critical to the survival of all living organisms. Many organisms can thrive on salt water, but the great majority of vascular plants and most insects, amphibians, reptiles, mammals and birds need fresh water to survive. Fresh water is the water resource that is of the most and immediate use to humans. Fresh water is not always pota ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Viviparous Fish
In animals, viviparity is development of the embryo inside the body of the mother, with the maternal circulation providing for the metabolic needs of the embryo's development, until the mother gives birth to a fully or partially developed juvenile that is at least metabolically independent. This is opposed to oviparity, where the embryos develop independently outside the mother in eggs until they are developed enough to break out as hatchlings; and ovoviviparity, where the embryos are developed in eggs that remain carried inside the mother's body until the hatchlings emerge from the mother as juveniles, similar to a live birth. Etymology The term "viviparity" and its adjective form "viviparous" both 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, w ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
