Threadfins are silvery grey

perciform Perciformes (), also called the Percomorpha or Acanthopteri, is an order or superorder of ray-finned fish. If considered a single order, they are the most numerous order of vertebrates, containing about 41% of all bony fish. Perciformes means " ...

fish Fish are aquatic, craniate, gill-bearing animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish as well as various extinct related groups. Approximately 95% of ...

of the

family Family (from la, familia) is a group of people related either by consanguinity (by recognized birth) or affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its members and of society. Idea ...

Polynemidae. Found in tropical to subtropical waters throughout the world, the threadfin family contains eight genera and about 40

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 s ...

. An unrelated species sometimes known by the name threadfin, ''Alectis indicus'', is properly the Indian threadfish (family

Carangidae The Carangidae are a family of ray-finned fish which includes the jacks, pompanos, jack mackerels, runners, and scads. It is the largest of the six families included within the order Carangiformes. Some authorities classify it as the only family ...

). Ranging in length from in the dwarf threadfin (''Parapolynemus verekeri'') to in fourfinger threadfin (''Eleutheronema tetradactylum'') and giant African threadfin (''Polydactylus quadrifilis''), threadfins are both important to commercial fisheries as a food fish, and popular among

angler Angler may refer to: * A fisherman who uses the fishing technique of angling * ''Angler'' (video game) * The angler, ''Lophius piscatorius'', a monkfish * More generally, any anglerfish in the order Lophiiformes * '' Angler: The Cheney Vice Pres ...

s. Their habit of forming large schools makes the threadfins a reliable and economic catch.

Description

Their bodies are elongated and fusiform, with spinous and soft

dorsal fin A dorsal fin is a fin located on the back of most marine and freshwater vertebrates within various taxa of the animal kingdom. Many species of animals possessing dorsal fins are not particularly closely related to each other, though through c ...

s widely separated. Their tail fins are large and deeply forked, indicating speed and agility. The mouth is large and inferior; a blunt snout projects far ahead. The jaws and palate possess bands of villiform (fibrous) teeth. Their most distinguishing feature is their

pectoral fins Fins are distinctive anatomical features composed of bony spines or rays protruding from the body of a fish. They are covered with skin and joined together either in a webbed fashion, as seen in most bony fish, or similar to a flipper, as see ...

: they are composed of two distinct sections, the lower of which consists of three to seven long, thread-like independent rays. ''Polynemus'' species may have up to 15 of these modified rays. In some species, such as the royal threadfin ('' Pentanemus quinquarius''), the thread-like rays may extend well past the tail fin. This feature explains both the common name threadfin and the family name Polynemidae, from the

Greek Greek may refer to: Greece Anything of, from, or related to Greece, a country in Southern Europe: *Greeks, an ethnic group. *Greek language, a branch of the Indo-European language family. **Proto-Greek language, the assumed last common ancestor ...

''poly'' meaning "many" and ''nema'' meaning "filament." Similar species, such as the mullets (family

Mugilidae The mullets or grey mullets are a family (Mugilidae) of ray-finned fish found worldwide in coastal temperate and tropical waters, and some species in fresh water. Mullets have served as an important source of food in Mediterranean Europe since R ...

) and

milkfish The milkfish (''Chanos chanos'') is the sole living species in the family Chanidae. However, there are at least five extinct genera from the Cretaceous. The repeating scientific name ( tautonym) is from Greek ( ‘mouth’). The species has man ...

(family Chanidae), can be easily distinguished from threadfins by their lack of filamentous pectoral rays.

Distribution and habitat

Threadfins frequent open, shallow water in areas with muddy, sandy, or silty bottoms; they are rarely seen at

reef A reef is a ridge or shoal of rock, coral or similar relatively stable material, lying beneath the surface of a natural body of water. Many reefs result from natural, abiotic processes— deposition of sand, wave erosion planing down rock o ...

s. Their pectoral rays are thought to serve as tactile structures, helping to find prey within the

sediment Sediment is a naturally occurring material that is broken down by processes of weathering and erosion, and is subsequently transported by the action of wind, water, or ice or by the force of gravity acting on the particles. For example, sa ...

s. Noted for being euryhaline, threadfins can tolerate a wide range of salinity levels. This attribute allows threadfins to enter

estuaries An estuary is a partially enclosed coastal body of brackish water with one or more rivers or streams flowing into it, and with a free connection to the open sea. Estuaries form a transition zone between river environments and maritime environmen ...

and even

river A river is a natural flowing watercourse, usually freshwater, flowing towards an ocean, sea, lake or another river. In some cases, a river flows into the ground and becomes dry at the end of its course without reaching another body of w ...

s. They feed primarily on crustaceans and smaller fish.

Reproduction

Presumed to be

pelagic The pelagic zone consists of the water column of the open ocean, and can be further divided into regions by depth (as illustrated on the right). The word ''pelagic'' is derived . The pelagic zone can be thought of as an imaginary cylinder or w ...

spawners, threadfins probably release many tiny, buoyant eggs into the water column, which then become part of the

plankton Plankton are the diverse collection of organisms found in water (or air) that are unable to propel themselves against a current (or wind). The individual organisms constituting plankton are called plankters. In the ocean, they provide a crucia ...

. The eggs float freely with the currents until hatching.

Cuisine

Threadfin has been used to create

crab stick Crab sticks, krab sticks, imitation crab (meat), or seafood sticks (originally known as ''kanikama'' in Japan) are a type of seafood made of starch and finely pulverized white fish (''surimi'') that has been shaped and cured to resemble the leg ...

Mariculture

Hawaii Hawaii ( ; haw, Hawaii or ) is a state in the Western United States, located in the Pacific Ocean about from the U.S. mainland. It is the only U.S. state outside North America, the only state that is an archipelago, and the only state ...

, sixfinger threadfins are the subject of commercial open-ocean cage mariculture.

Genera and species

Elegant paradiseus fish Polynemus multifilis

The species in eight genera are: * Genus ''

Eleutheronema ''Eleutheronema'' is a genus of marine ray-finned fish from the family Polynemidae, the threadfins. These fishes occur in the Indian Ocean and the western Pacific Ocean. Species The following species are classified within the genus ''Eleutherone ...

'' ** ''

Eleutheronema rhadinum ''Eleutheronema'' is a genus of marine ray-finned fish from the family Polynemidae, the threadfins. These fishes occur in the Indian Ocean and the western Pacific Ocean. Species The following species are classified within the genus ''Eleutherone ...

'' (

Jordan Jordan ( ar, الأردن; tr. ' ), officially the Hashemite Kingdom of Jordan,; tr. ' is a country in Western Asia. It is situated at the crossroads of Asia, Africa, and Europe, within the Levant region, on the East Bank of the Jordan Rive ...

& Evermann, 1902) (East Asian fourfinger threadfin) ** ''

Eleutheronema tetradactylum ''Eleutheronema tetradactylum'', the fourfinger threadfin, is a species of marine ray-finned fish, a threadfin from the family Polynemidae which occurs in the Indian and western Pacific Ocean. Description ''Eleutheronema tetradactylum'' has two ...

'' (Shaw, 1804) (Fourfinger threadfin) ** ''

Eleutheronema tridactylum ''Eleutheronema'' is a genus of marine ray-finned fish from the family Polynemidae, the threadfins. These fishes occur in the Indian Ocean and the western Pacific Ocean. Species The following species are classified within the genus ''Eleutherone ...

'' ( Bleeker, 1849) (Threefinger threadfin) * Genus '' Filimanus'' ** '' Filimanus heptadactyla'' ( Cuvier, 1829) (Sevenfinger threadfin) ** '' Filimanus hexanema'' (Cuvier 1829) (Javanese threadfin) ** '' Filimanus perplexa'' Feltes 1991 (Splendid threadfin) ** '' Filimanus sealei'' (

& Richardson, 1910) (Eightfinger threadfin) ** '' Filimanus similis'' Feltes 1991 (Indian sevenfinger threadfin) ** '' Filimanus xanthonema'' (

Valenciennes Valenciennes (, also , , ; nl, label=also Dutch, Valencijn; pcd, Valincyinnes or ; la, Valentianae) is a commune in the Nord department, Hauts-de-France, France. It lies on the Scheldt () river. Although the city and region experienced a ...

, 1831) (Yellowthread threadfin) * Genus '' Galeoides'' ** '' Galeoides decadactylus'' ( Bloch, 1795) (

Lesser African threadfin The lesser African threadfin (''Galeoides decadactylus'') is a species of marine ray-finned fish, a threadfin from the family Polynemidae which is found in the eastern Atlantic Ocean off the western coast of Africa. Description The lesser Afric ...

) * Genus '' Leptomelanosoma'' ** '' Leptomelanosoma indicum'' (Shaw, 1804) ( Indian threadfin) * Genus '' Parapolynemus'' ** '' Parapolynemus verekeri'' ( Saville-Kent, 1889) ( Dwarf paradise fish) * Genus '' Pentanemus'' ** '' Pentanemus quinquarius'' (

Linnaeus Carl Linnaeus (; 23 May 1707 – 10 January 1778), also known after his ennoblement in 1761 as Carl von Linné Blunt (2004), p. 171. (), was a Swedish botanist, zoologist, taxonomist, and physician who formalised binomial nomenclature, the ...

, 1758) ( Royal threadfin) * Genus ''

Polydactylus ''Polydactylus'' is a genus of threadfin that mainly are native to the Indian, Atlantic and Pacific Oceans, especially in coastal or brackish waters (such as mangrove or estuaries). Some may even enter rivers and a single, ''P. macrophthalmus'', ...

'' (likely not monophyletic) ** ''

Polydactylus approximans ''Polydactylus'' is a genus of threadfin that mainly are native to the Indian, Atlantic and Pacific Oceans, especially in coastal or brackish waters (such as mangrove or estuaries). Some may even enter rivers and a single, ''P. macrophthalmus'', ...

'' ( Lay & Bennett, 1839) (Blue bobo) ** ''

Polydactylus bifurcus ''Polydactylus'' is a genus of threadfin that mainly are native to the Indian, Atlantic and Pacific Oceans, especially in coastal or brackish waters (such as mangrove or estuaries). Some may even enter rivers and a single, ''P. macrophthalmus'', ...

'' Motomura, Kimura & Iwatsuki, 2001 (Slender fivefinger threadfin) ** ''

Polydactylus longipes ''Polydactylus'' is a genus of threadfin that mainly are native to the Indian, Atlantic and Pacific Oceans, especially in coastal or brackish waters (such as mangrove or estuaries). Some may even enter rivers and a single, ''P. macrophthalmus'', ...

'' Motomura, Okamoto & Iwatsuki, 2001 (Long-limb threadfin) ** ''

Polydactylus luparensis ''Polydactylus'' is a genus of threadfin that mainly are native to the Indian, Atlantic and Pacific Oceans, especially in coastal or brackish waters (such as mangrove or estuaries). Some may even enter rivers and a single, ''P. macrophthalmus'', ...

'' Lim, Motomura &

Gambang A gambang, properly called a gambang kayu ('wooden gambang') is a xylophone-like instrument used among people of Indonesia in gamelan and kulintang, with wooden bars as opposed to the metallic ones of the more typical metallophones in a gamelan ...

, 2010 (Sarawak giant threadfin) ** '' Polydactylus macrochir'' ( Günther, 1867) ( King threadfin) ** ''

Polydactylus macrophthalmus ''Polydactylus'' is a genus of threadfin that mainly are native to the Indian, Atlantic and Pacific Oceans, especially in coastal or brackish waters (such as mangrove or estuaries). Some may even enter rivers and a single, ''P. macrophthalmus'', ...

'' ( Bleeker, 1858) (River threadfin) ** ''

Polydactylus malagasyensis ''Polydactylus'' is a genus of threadfin that mainly are native to the Indian, Atlantic and Pacific Oceans, especially in coastal or brackish waters (such as mangrove or estuaries). Some may even enter rivers and a single, ''P. macrophthalmus'', ...

'' Motomura & Iwatsuki, 2001 (African blackspot threadfin) ** ''

Polydactylus microstomus ''Polydactylus'' is a genus of threadfin that mainly are native to the Indian, Atlantic and Pacific Oceans, especially in coastal or brackish waters (such as mangrove or estuaries). Some may even enter rivers and a single, ''P. macrophthalmus'', ...

'' ( Bleeker, 1851) (Smallmouth threadfin) ** ''

Polydactylus mullani ''Polydactylus'' is a genus of threadfin that mainly are native to the Indian, Atlantic and Pacific Oceans, especially in coastal or brackish waters (such as mangrove or estuaries). Some may even enter rivers and a single, ''P. macrophthalmus'', ...

'' (Hora, 1926) (Arabian blackspot threadfin) ** ''

Polydactylus multiradiatus ''Polydactylus'' is a genus of threadfin that mainly are native to the Indian, Atlantic and Pacific Oceans, especially in coastal or brackish waters (such as mangrove or estuaries). Some may even enter rivers and a single, ''P. macrophthalmus'', ...

'' ( Günther, 1860) (Australian threadfin) ** ''

Polydactylus nigripinnis ''Polydactylus'' is a genus of threadfin that mainly are native to the Indian, Atlantic and Pacific Oceans, especially in coastal or brackish waters (such as mangrove or estuaries). Some may even enter rivers and a single, ''P. macrophthalmus'', ...

Munro A Munro () is defined as a mountain in Scotland with a height over , and which is on the Scottish Mountaineering Club (SMC) official list of Munros; there is no explicit topographical prominence requirement. The best known Munro is Ben Nev ...

, 1964 (Blackfin threadfin) ** ''

Polydactylus octonemus The Atlantic threadfin (''Polydactylus octonemus'') is a species of ray-finned fish a threadfin from the family Polynemidae which is native to subtropical and temperate waters of the western Atlantic Ocean and the Gulf of Mexico. Description T ...

'' ( Girard, 1858) (Atlantic threadfin) ** ''

Polydactylus oligodon ''Polydactylus'' is a genus of threadfin that mainly are native to the Indian, Atlantic and Pacific Oceans, especially in coastal or brackish waters (such as mangrove or estuaries). Some may even enter rivers and a single, ''P. macrophthalmus'', ...

'' ( Günther, 1860) (Littlescale threadfin) ** '' Polydactylus opercularis'' Seale & Bean, 1907 (Yellow bobo) ** '' Polydactylus persicus'' Motomura & Iwatsuki, 2001 (Persian blackspot threadfin) ** ''

Polydactylus plebeius ''Polydactylus plebeius'', the striped threadfin, also known as the common threadfin, Northern threadfin or puttynose, is a species of marine fish native to the Indo-Pacific. Description ''Polydactylus plebeius'' is a medium-sized threadfin whic ...

'' ( Broussonet, 1782) (Striped threadfin) ** '' Polydactylus quadrifilis'' ( Cuvier, 1829) (Giant African threadfin) ** '' Polydactylus sexfilis'' (

, 1831) (Sixfinger threadfin) ** '' Polydactylus sextarius'' ( Bloch & Schneider, 1801) (Blackspot threadfin) ** '' Polydactylus siamensis'' Motomura, Iwatsuki &

Yoshino Yoshino may refer to: * Yoshino cherry, another name for ''Prunus × yedoensis'', a flowering cherry tree * Japanese cruiser Yoshino, Japanese cruiser ''Yoshino'', a protected cruiser of the Imperial Japanese Navy Places * Yoshino, Nara, a town ...

, 2001 (Largemouth striped threadfin) ** ''

Polydactylus virginicus ''Polydactylus'' is a genus of threadfin that mainly are native to the Indian, Atlantic and Pacific Oceans, especially in coastal or brackish waters (such as mangrove or estuaries). Some may even enter rivers and a single, ''P. macrophthalmus'', ...

'' (

, 1758) (Barbu) * Genus ''

Polynemus ''Polynemus'' is a genus of threadfins (family Polynemidae). They are native to South and Southeast Asia and, depending on the species, occur in freshwater, brackish, and/or marine environments. The family Polynemidae is characterized by the pec ...

'' ** '' Polynemus aquilonaris'' Motomura, 2003 ( Northern paradise fish) ** ''

Polynemus bidentatus ''Polynemus'' is a genus of threadfins (family Polynemidae). They are native to South and Southeast Asia and, depending on the species, occur in freshwater, brackish, and/or marine environments. The family Polynemidae is characterized by the pec ...

'' Motomura & Tsukawaki, 2006 ** '' Polynemus dubius'' Bleeker, 1854 ( Eastern paradise fish) ** '' Polynemus hornadayi''

Myers Myers as a surname has several possible origins, e.g. Old French ("physician"), Old English ("mayor"), and Old Norse ("marsh"). People * Abram F. Myers (born 1889), chair of the Federal Trade Commission and later general counsel and board ch ...

, 1936 ( Hornaday's paradise fish) ** ''

Polynemus kapuasensis ''Polynemus'' is a genus of threadfins (family Polynemidae). They are native to South and Southeast Asia and, depending on the species, occur in freshwater, brackish, and/or marine environments. The family Polynemidae is characterized by the pec ...

'' Motomura & van Oijen, 2003 ( Kapuas elegant paradise fish) ** ''

Polynemus melanochir ''Polynemus'' is a genus of threadfins (family Polynemidae). They are native to South and Southeast Asia and, depending on the species, occur in freshwater, brackish, and/or marine environments. The family Polynemidae is characterized by the pec ...

, 1831 ( Blackhand paradise fish) ** '' Polynemus multifilis''

Temminck Coenraad Jacob Temminck (; 31 March 1778 – 30 January 1858) was a Dutch aristocrat, zoologist and museum director. Biography Coenraad Jacob Temminck was born on 31 March 1778 in Amsterdam in the Dutch Republic. From his father, Jacob Temmin ...

Schlegel Schlegel is a German occupational surname. Notable people with the surname include: * Anthony Schlegel (born 1981), former American football linebacker * August Wilhelm Schlegel (1767–1845), German poet, older brother of Friedrich * Brad Schlege ...

, 1843 ( Elegant paradise fish) ** '' Polynemus paradiseus''

, 1758 (

Paradise threadfin The paradise threadfin (''Polynemus paradiseus'') is a species of catadromous ray-finned fish, a threadfin from the family Polynemidae which is found in south and southeast Asia in freshwater rivers where it is a valued food fish. Description ...

)

Timeline of genera

ImageSize = width:1000px height:auto barincrement:15px PlotArea = left:10px bottom:50px top:10px right:10px Period = from:-65.5 till:10 TimeAxis = orientation:horizontal ScaleMajor = unit:year increment:5 start:-65.5 ScaleMinor = unit:year increment:1 start:-65.5 TimeAxis = orientation:hor AlignBars = justify Colors = #legends id:CAR value:claret id:ANK value:rgb(0.4,0.3,0.196) id:HER value:teal id:HAD value:green id:OMN value:blue id:black value:black id:white value:white id:cenozoic value:rgb(0.54,0.54,0.258) id:paleogene value:rgb(0.99,0.6,0.32) id:paleocene value:rgb(0.99,0.65,0.37) id:eocene value:rgb(0.99,0.71,0.42) id:oligocene value:rgb(0.99,0.75,0.48) id:neogene value:rgb(0.999999,0.9,0.1) id:miocene value:rgb(0.999999,0.999999,0) id:pliocene value:rgb(0.97,0.98,0.68) id:quaternary value:rgb(0.98,0.98,0.5) id:pleistocene value:rgb(0.999999,0.95,0.68) id:holocene value:rgb(0.999,0.95,0.88) BarData= bar:eratop bar:space bar:periodtop bar:space bar:NAM1 bar:NAM2 bar:space bar:period bar:space bar:era PlotData= align:center textcolor:black fontsize:M mark:(line,black) width:25 shift:(7,-4) bar:periodtop from: -65.5 till: -55.8 color:paleocene text:

Paleocene The Paleocene, ( ) or Palaeocene, is a geological epoch that lasted from about 66 to 56 million years ago (mya). It is the first epoch of the Paleogene Period in the modern Cenozoic Era. The name is a combination of the Ancient Greek ''pal ...

from: -55.8 till: -33.9 color:eocene text:

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'', " ...

from: -33.9 till: -23.03 color:oligocene text: Oligocene from: -23.03 till: -5.332 color:miocene text:

Miocene The Miocene ( ) is the first epoch (geology), geological epoch of the Neogene Period and extends from about (Ma). The Miocene was named by Scottish geologist Charles Lyell; the name comes from the Greek words (', "less") and (', "new") and mea ...

from: -5.332 till: -2.588 color:pliocene text: Plio. from: -2.588 till: -0.0117 color:pleistocene text:

Pleist. The Pleistocene ( , often referred to as the ''Ice age'') is the geological epoch that lasted from about 2,580,000 to 11,700 years ago, spanning the Earth's most recent period of repeated glaciations. Before a change was finally confirmed in ...

from: -0.0117 till: 0 color:holocene text: H. bar:eratop from: -65.5 till: -23.03 color:paleogene text: Paleogene from: -23.03 till: -2.588 color:neogene text: Neogene from: -2.588 till: 0 color:quaternary text: Q. PlotData= align:left fontsize:M mark:(line,white) width:5 anchor:till align:left color:miocene bar:NAM1 from: -23.03 till: 0 text: Pentanemus color:miocene bar:NAM2 from: -11.608 till: 0 text:

PlotData= align:center textcolor:black fontsize:M mark:(line,black) width:25 bar:period from: -65.5 till: -55.8 color:paleocene text:

from: -55.8 till: -33.9 color:eocene text:

from: -33.9 till: -23.03 color:oligocene text: Oligocene from: -23.03 till: -5.332 color:miocene text:

from: -5.332 till: -2.588 color:pliocene text: Plio. from: -2.588 till: -0.0117 color:pleistocene text:

from: -0.0117 till: 0 color:holocene text: H. bar:era from: -65.5 till: -23.03 color:paleogene text: Paleogene from: -23.03 till: -2.588 color:neogene text: Neogene from: -2.588 till: 0 color:quaternary text: Q.

References

* *

External links

Fisheries Western Australia - Threadfins Fact SheetThe Paradise threadfin, Polynemus paradiseus
{{Taxonbar, from=Q924957 Fish of Hawaii Taxa named by Constantine Samuel Rafinesque id:Senangin