Fish, AGN-CLU
Fishes have been in existence for more than 450 million years, and they have evolved to fit into almost every conceivable type of aquatic habitat, including both fresh and salt waters. Almost all natural bodies of water bear fish life, with the exception of very hot thermal ponds and extremely salt-alkaline lakes, such as the Dead Sea in Asia and the Great Salt Lake in North America. Although most fish species are cold-blooded, one especially contrarian species, the opah (Lampris guttatus), is warm-blooded.
Fish Encyclopedia Articles By Title
agnathan, (superclass Agnatha), any member of the group of primitive jawless fishes that includes the lampreys......
aholehole, any of several species of fishes constituting the family Kuhliidae (order Perciformes). Various members......
Alaska blackfish, (species Dallia pectoralis), Arctic freshwater fish, assigned by most authorities to the family......
albacore, (species Thunnus alalunga), large oceanic fish noted for its fine flesh. The bluefin tuna (T. thynnus)......
alewife, (Pomolobus, or Alosa, pseudoharengus), important North American food fish of the herring family, Clupeidae.......
alfonsino, any of the eight species of exclusively marine fishes constituting the family Berycidae (order Beryciformes).......
amberjack, any of several popular sport fishes. See...
anchovy, any of numerous schooling saltwater fishes of the family Engraulidae (order Clupeiformes) related to the......
anemone fish, (genus Amphiprion), any of about 30 species of Indo-Pacific fishes constituting the genus Amphiprion......
angel shark, (genus Squatina), any of at least 22 species of sharks that constitute a single genus (family Squatinidae,......
angelfish, any of various unrelated fishes of the order Perciformes. The angelfishes, or scalares, popular in home......
anglerfish, any of about 210 species of marine fishes of the order Lophiiformes. Anglers are named for their method......
antiarch, any of an order of extinct, mainly freshwater, jawed fishes, class Placodermi, abundant during Middle......
arawana, (species Osteoglossum bicirrhosum), freshwater fish of tropical South America in the family Osteoglossidae......
archer fish, any of seven species of Indo-Pacific fishes of the family Toxotidae (order Perciformes) noted for......
Arctolepis, extinct genus of placoderms (fishlike animals) present during the early part of the Devonian Period......
argentine, any fish of the family Argentinidae, small, outwardly smeltlike fishes found in deeper waters of the......
arthrodire, any member of an order of extinct, armoured, jawed fishes (placoderms) found in Devonian freshwater......
Asian carp, any of several species of fish belonging to the carp family (Cyprinidae) that are native to eastern......
atheriniform, any member of the order Atheriniformes, containing 15 families of marine and freshwater spiny-finned......
Atlantic herring, (Clupea harengus), species of herring in the family Clupeidae (order Clupeiformes) and one of......
Atlantic salmon, (species Salmo salar), oceanic trout of the family Salmonidae, a highly prized game fish. It averages......
barb, (genus Barbus), any of numerous freshwater fishes belonging to a genus in the carp family, Cyprinidae. The......
barracuda, any of about 20 species of predacious fishes of the family Sphyraenidae (order Perciformes). Barracudas......
barracudina, any of about 50 species of marine fishes of the family Paralepididae, found almost worldwide in deep......
barramundi, (Lates calcarifer), species of fish in the family Latidae (order Perciformes) that is native to tropical......
basking shark, (Cetorhinus maximus), huge, slow-swimming shark of the family Cetorhinidae. Named for its habit......
bass, in zoology, any of a large number of fishes, many of them valued for food or sport. The name bass covers......
batfish, any of about 60 species of fishes of the family Ogcocephalidae (order Lophiiformes), found in warm and......
beardfish, any of the five species of fishes in the genus Polymixia constituting the family Polymixiidae (order......
bib, common fish of the cod family, Gadidae, found in the sea along European coastlines. The bib is a rather deep-bodied......
bichir, (genus Polypterus), any of about 10 species of air-breathing tropical fishes of the genus Polypterus native......
bigeye, any of about 18 species of marine fishes comprising the family Priacanthidae (order Perciformes). Some......
billfish, any of a group of long-jawed fishes (usually swordfish, marlin, and allies) that sometimes includes the......
bioelectric organ, system of tissues specialized for the production and use of electrical power in a living organism.......
Birkenia, genus of extinct early fishlike vertebrates found in Late Silurian and Early Devonian rocks in Europe......
bitterling, (Rhodeus), any of several small, carplike fish of the family Cyprinidae noted for their unusual manner......
black bass, any of about six species of elongated freshwater fishes that constitute the genus Micropterus of the......
black shark, either of two Asian species of river fishes. See...
blackfish, name given to various dark-coloured fishes, including the tautog (see wrasse), bowfin, Alaska blackfish,......
blacktip shark, any of several shark species in the family Carcharhinidae. See...
bleak, (Alburnus alburnus), small, slender fish of the carp family, Cyprinidae, found in rivers and lakes of England......
blenny, any of the numerous and diverse fishes of the suborder Blennioidei (order Perciformes). Blennies are mostly......
blind fish, any of various eyeless fishes, among them several unrelated cave-dwelling species of the families Amblyopsidae,......
bloodfin, freshwater fish, a species of characin...
blue shark, (Prionace glauca), shark of the family Carcharhinidae found in tropical and temperate oceans. The blue......
blueback, common name for a number of blue-coloured fishes, particularly the lake herring, or cisco, a whitefish......
bluefish, (Pomatomus saltatrix), swift-moving marine food and game fish, the only member of the family Pomatomidae......
bluegill, (Lepomis macrochirus), popular game fish in the sunfish family, Centrarchidae (order Perciformes). It......
boarfish, (family Caproidae), any of six species of fishes (order Zeiformes) characterized by red coloration and......
Bombay duck, (Harpadon nehereus), fish of the family Synodontidae, found in estuaries of northern India, where......
bonefish, (Albula vulpes), marine game fish of the family Albulidae (order Elopiformes). It inhabits shallow coastal......
bonito, (genus Sarda), tunalike schooling fish of the tuna and mackerel family, Scombridae (order Perciformes).......
bony fish, (superclass Osteichthyes), any member of the superclass Osteichthyes, a group made up of the classes......
bony tongue, any of several heavy-bodied tropical river fishes, family Osteoglossidae, covered with large, hard,......
Bothriolepis, genus of extinct fishes of the order Antiarcha, class Placodermi, characteristic of the Middle and......
bowfin, (Amia calva), freshwater fish of the order Amiiformes (infraclass Holostei); it is the only recognized......
boxfish, any of a small group of shallow-water marine fishes of the family Ostraciontidae (or Ostraciidae), distinguished......
bream, (Abramis brama), common European food and game fish of the carp family, Cyprinidae, found in lakes and slow......
bristlemouth, (family Gonostomatidae), any of the approximately 33 species of oceanic fishes (order Stomiiformes),......
bristling, (Sprattus sprattus), edible fish of the herring family Clupeidae (order Clupeiformes). Bristlings are......
brook trout, (Salvelinus fontinalis), popular freshwater game fish, a variety of char, regarded for its flavour......
brotula, any of about 200 to 220 species of marine fishes placed by some authorities with the cusk eels in the......
brown trout, prized and wary European game fish favoured for the table. The brown trout, which includes several......
bull shark, (Carcharhinus leucas), species of large predatory shark found in shallow coastal lagoons, estuaries,......
bullhead, any of several North American freshwater catfishes of the genus Ameiurus (Ictalurus of some authorities)......
bullhead shark, (genus Heterodontus), any shark of the genus Heterodontus, known for its broad head, small mouth,......
burbot, (Lota lota), elongated fish of the family Lotidae that inhabits cold rivers and lakes of Europe, Asia,......
butterfish, any of the thin, deep-bodied, more or less oval and silvery fishes of the family Stromateidae (order......
butterfly ray, any of several stingray (q.v.) species in the family...
butterflyfish, any of the approximately 115 species of small quick-moving marine fishes in the family Chaetodontidae......
candiru, (Vandellia cirrhosa), scaleless, parasitic catfish of the family Trichomycteridae found in the Amazon......
candlefish, species of smelt of the genus Thaleichthys...
capelin, (Mallotus villosus), marine food fish, a species of smelt, in the family Osmeridae (order Osmeriformes).......
carangid, any fish of the family Carangidae (order Perciformes), which contains more than 200 species of marine......
carcharhinid, any member of the shark family Carcharhinidae, which includes 12 genera and about 50 species found......
cardinal fish, any fish of the family Apogonidae (order Perciformes), a group including about 200 species of small,......
carp, widely, any of several fish species classified in the genus Cyprinus in the family Cyprinidae but usually,......
carpet shark, (order Orectolobiformes), any of about 40 species of sharks possessing mottled patterns on the body......
cat shark, any of more than 150 species of small mottled sharks (order Carcharhiniformes). Most are less than 90......
catfish, any of the fishes of the order Siluriformes. Catfishes are related to the characins, carp, and minnows......
cave fish, any of the pale, blind, cave-dwelling fishes of the genera Amblyopsis and Typhlichthys, family Amblyopsidae.......
Cephalaspis, extinct genus of very primitive, jawless, fishlike vertebrates found in Lower Devonian rocks (the......
char, (Salvelinus), any of several freshwater food and game fishes distinguished from the similar trout by light,......
characin, any of the numerous freshwater fishes of the family Characidae. Hundreds of species of characins are......
Cheirolepis, extinct genus of primitive fishes whose fossils are found in European and North American rocks of......
chimaera, (subclass Holocephali), any of numerous cartilaginous fishes related to sharks and rays in the class......
chinook salmon, (Oncorhynchus tshawytscha) prized North Pacific food and sport fish of the family Salmonidae. It......
chondrichthyan, (class Chondrichthyes), any member of the diverse group of cartilaginous fishes that includes the......
chondrostean, (subclass Chondrostei), any of approximately 30 species of primitive ray-finned bony fishes that......
Chondrosteiformes, an extinct order of ray-finned saltwater fishes (class Actinopterygii) comprising a single family......
chub, any of several freshwater fishes of the carp family, Cyprinidae, common in Europe and North America. Chubs......
chum salmon, (Oncorhynchus keta), lightly speckled North Pacific fish, family Salmonidae, weighing up to 15 kg......
cichlid, any of more than 1,300 species of fishes of the family Cichlidae (order Perciformes), many of which are......
cisco, herringlike type of whitefish...
Cladoselache, genus of extinct sharks, known from fossilized remains in Upper Devonian rocks (formed 385–359 million......
Climatius, genus of extinct, primitive jawed vertebrates common as fossils in Devonian rocks in Europe and North......
climbing perch, (Anabas testudineus), small Asian freshwater fish of the family Anabantidae (order Perciformes)......
clingfish, any of more than 150 species of small fishes of the family Gobiesocidae (order Perciformes). Clingfishes......
clupeiform, (order Clupeiformes), any member of the superorder Clupeomorpha, a group of bony fishes with one living......