Alectis
Encyclopedia
Alectis is a genus
of fish
in the family
Carangidae
containing three extant species
, all of which are large marine
fishes. They are commonly known as threadfish, diamond trevallies and occasionally pompanos, although they have no close affiliation with the true pompano
genus.
. The Carangidae are perciform fishes in the suborder Percoidei
.
The first fish in the genus to be described was Alectis ciliaris under the genus name of Zeus, part of the dory
family. Lacépède recognized the species was not a dory and assigned it to a new genus, Gallus, however this was preoccupied by a bird
. In 1815, Rafinesque proposed the name Alectis, into which three species were eventually placed. Georges Cuvier
proposed a second name, Scyris for the genus in 1829, but Alectis had priority and has therefore been cemented for the time being. The name Alectis is derived from one of three Erinyes
in the Greek mythology
; daughter of Acheronte with a terrible rage.
A single species has been identified the fossil record; Alectis simus, from the Eocene
period of England. It was found alongside a number of extinct and extant carangid genera including Caranx and Usacaranx (extinct).
Note: Extinct species denoted with a cross †
s, with the main difference being the profile of the head and the characteristic long filamentous anal and dorsal fins displayed by juvenile
s of these species. They are generally a silver colour, with pale green to hyaline
fins. A. indica is the largest of the genus, growing to a reported 165 m and 25 kg in weight.
The genus has a circum-tropical
distribution, with adults generally restricted to reef
s in coastal areas down to 100 m, while juveniles are often pelagic. All three are predators of small fishes, cephalopod
s and crustacean
s. A little is known of their reproductive habits and larval phases, with spawning
occurring during daylight
between pairs.
and subsistence fisheries, with the species generally not numerous enough to warrant a specific fishery. All species are considered fine game fish
, attaining large sizes and capable of blistering runs. The flesh
of the genus is generally considered very good for culinary purposes, although at least one species has been implicated in a case of Ciguatera
poisoning. In Singapore
, A. indica has successfully been bred in aquaculture
for food production in relatively low numbers. Juveniles are occasionally used in saltwater aquariums, noted for their filamentous anal and dorsal fins.
Genus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
of fish
Fish
Fish are a paraphyletic group of organisms that consist of all gill-bearing aquatic vertebrate 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...
in the family
Family (biology)
In biological classification, family is* a taxonomic rank. Other well-known ranks are life, domain, kingdom, phylum, class, order, genus, and species, with family fitting between order and genus. As for the other well-known ranks, there is the option of an immediately lower rank, indicated by the...
Carangidae
Carangidae
Carangidae is a family of fish which includes the jacks, pompanos, jack mackerels, and scads.They are marine fish found in the Atlantic, Indian and Pacific Oceans...
containing three extant species
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
, all of which are large marine
Marine (ocean)
Marine is an umbrella term. As an adjective it is usually applicable to things relating to the sea or ocean, such as marine biology, marine ecology and marine geology...
fishes. They are commonly known as threadfish, diamond trevallies and occasionally pompanos, although they have no close affiliation with the true pompano
Pompano
Pompanos are marine fishes in the Trachinotus genus of the Carangidae family . Pompano may also refer to various other, similarly shaped members of Carangidae, or the order Perciformes. Their appearance is deep bodied and mackerel-like, typically silver and toothless with a forked tail and...
genus.
Taxonomy
Alectis is one of 33 genera in the jack and horse mackerel family CarangidaeCarangidae
Carangidae is a family of fish which includes the jacks, pompanos, jack mackerels, and scads.They are marine fish found in the Atlantic, Indian and Pacific Oceans...
. The Carangidae are perciform fishes in the suborder Percoidei
Percoidei
Percoidei is one of eighteen suborders of bony fish in the order Perciformes. Many commercially harvested fish species are contained in this suborder, including the snappers, jacks, whitings, groupers, bass, perches and porgies.-Divisions:...
.
The first fish in the genus to be described was Alectis ciliaris under the genus name of Zeus, part of the dory
Dory
The dory is a small, shallow-draft boat, about long. It is a lightweight and versatile boat with high sides, a flat bottom and sharp bows. They are easy to build because of their simple lines. For centuries, dories have been used as traditional fishing boats, both in coastal waters and in the...
family. Lacépède recognized the species was not a dory and assigned it to a new genus, Gallus, however this was preoccupied by a bird
Bird
Birds are feathered, winged, bipedal, endothermic , egg-laying, vertebrate animals. Around 10,000 living species and 188 families makes them the most speciose class of tetrapod vertebrates. They inhabit ecosystems across the globe, from the Arctic to the Antarctic. Extant birds range in size from...
. In 1815, Rafinesque proposed the name Alectis, into which three species were eventually placed. Georges Cuvier
Georges Cuvier
Georges Chrétien Léopold Dagobert Cuvier or Jean Léopold Nicolas Frédéric Cuvier , known as Georges Cuvier, was a French naturalist and zoologist...
proposed a second name, Scyris for the genus in 1829, but Alectis had priority and has therefore been cemented for the time being. The name Alectis is derived from one of three Erinyes
Erinyes
In Greek mythology the Erinyes from Greek ἐρίνειν " pursue, persecute"--sometimes referred to as "infernal goddesses" -- were female chthonic deities of vengeance. A formulaic oath in the Iliad invokes them as "those who beneath the earth punish whosoever has sworn a false oath"...
in the Greek mythology
Greek mythology
Greek mythology is the body of myths and legends belonging to the ancient Greeks, concerning their gods and heroes, the nature of the world, and the origins and significance of their own cult and ritual practices. They were a part of religion in ancient Greece...
; daughter of Acheronte with a terrible rage.
A single species has been identified the fossil record; Alectis simus, from the Eocene
Eocene
The Eocene Epoch, lasting from about 56 to 34 million years ago , is a major division of the geologic timescale and the second epoch of the Paleogene Period in the Cenozoic Era. The Eocene spans the time from the end of the Palaeocene Epoch to the beginning of the Oligocene Epoch. The start of the...
period of England. It was found alongside a number of extinct and extant carangid genera including Caranx and Usacaranx (extinct).
Species
- African threadfishAfrican threadfishThe African threadfish, Alectis alexandrinus, is a large species of marine fish in the jack family, Carangidae. The species is distributed along the coast of tropical Africa in the eastern Atlantic Ocean, extending to the Mediterranean Sea. Adults live predominantly in shallow waters shallower...
, Alectis alexandrinus (Geoffroy Saint-HilaireÉtienne Geoffroy Saint-HilaireÉtienne Geoffroy Saint-Hilaire was a French naturalist who established the principle of "unity of composition". He was a colleague of Jean-Baptiste Lamarck and expanded and defended Lamarck's evolutionary theories...
, 1817) - African pompanoAfrican pompanoThe African pompano, Alectis ciliaris, is a widely distributed species of tropical marine fish in the Jack family, Carangidae. The species is found in tropical waters worldwide, with adults often inhabiting coastlines while juveniles are usually pelagic, floating with ocean currents...
, Alectis ciliaris (BlochMarcus Elieser BlochMarcus Elieser Bloch was a German medical doctor and naturalist. He is generally considered one of the most important ichthyologists of the 18th century.- Life :...
, 1787) - Indian threadfishIndian threadfishThe Indian threadfish, Alectis indicus, is a large species of coastal marine fish of the jack family, Carangidae. The species is widespread in the waters of the tropical Indo-West Pacific Ocean, ranging from east Africa to India, Asia, Indonesia and Australia...
, Alectis indicus (RuppellEduard RüppellWilhelm Peter Eduard Simon Rüppell was a German naturalist and explorer. Rüppell is occasionally transliterated to "Rueppell" for the English alphabet....
, 1830) - Alectis simus (Stinton, 1979) †
Note: Extinct species denoted with a cross †
Biology
The fish of the genus are large, powerful fishes that look very similar to a number of other large jackCarangidae
Carangidae is a family of fish which includes the jacks, pompanos, jack mackerels, and scads.They are marine fish found in the Atlantic, Indian and Pacific Oceans...
s, with the main difference being the profile of the head and the characteristic long filamentous anal and dorsal fins displayed by juvenile
Juvenile (organism)
A juvenile is an individual organism that has not yet reached its adult form, sexual maturity or size. Juveniles sometimes look very different from the adult form, particularly in terms of their colour...
s of these species. They are generally a silver colour, with pale green to hyaline
Hyaline
The term hyaline denotes a substance with a glass-like appearance.-Histopathology:In histopathological medical usage, a hyaline substance appears glassy and pink after being stained with haematoxylin and eosin — usually it is an acellular, proteinaceous material...
fins. A. indica is the largest of the genus, growing to a reported 165 m and 25 kg in weight.
The genus has a circum-tropical
Tropics
The tropics is a region of the Earth surrounding the Equator. It is limited in latitude by the Tropic of Cancer in the northern hemisphere at approximately N and the Tropic of Capricorn in the southern hemisphere at S; these latitudes correspond to the axial tilt of the Earth...
distribution, with adults generally restricted to reef
Reef
In nautical terminology, a reef is a rock, sandbar, or other feature lying beneath the surface of the water ....
s in coastal areas down to 100 m, while juveniles are often pelagic. All three are predators of small fishes, cephalopod
Cephalopod
A cephalopod is any member of the molluscan class Cephalopoda . These exclusively marine animals are characterized by bilateral body symmetry, a prominent head, and a set of arms or tentacles modified from the primitive molluscan foot...
s and crustacean
Crustacean
Crustaceans form a very large group of arthropods, usually treated as a subphylum, which includes such familiar animals as crabs, lobsters, crayfish, shrimp, krill and barnacles. The 50,000 described species range in size from Stygotantulus stocki at , to the Japanese spider crab with a leg span...
s. A little is known of their reproductive habits and larval phases, with spawning
Spawn (biology)
Spawn refers to the eggs and sperm released or deposited, usually into water, by aquatic animals. As a verb, spawn refers to the process of releasing the eggs and sperm, also called spawning...
occurring during daylight
Daylight
Daylight or the light of day is the combination of all direct and indirect sunlight outdoors during the daytime. This includes direct sunlight, diffuse sky radiation, and both of these reflected from the Earth and terrestrial objects. Sunlight scattered or reflected from objects in outer space is...
between pairs.
Relationship to humans
The genus is of minor importance to both commercialFishery
Generally, a fishery is an entity engaged in raising or harvesting fish which is determined by some authority to be a fishery. According to the FAO, a fishery is typically defined in terms of the "people involved, species or type of fish, area of water or seabed, method of fishing, class of boats,...
and subsistence fisheries, with the species generally not numerous enough to warrant a specific fishery. All species are considered fine game fish
Game fish
Game fish are fish pursued for sport by recreational anglers. They can be freshwater or marine fish. Game fish can be eaten after being caught, though increasingly anglers practise catch and release to improve fish populations. Some game fish are also targeted commercially, particularly...
, attaining large sizes and capable of blistering runs. The flesh
Fish (food)
Fish is a food consumed by many species, including humans. The word "fish" refers to both the animal and to the food prepared from it. Fish has been an important source of protein for humans throughout recorded history.-Terminology:...
of the genus is generally considered very good for culinary purposes, although at least one species has been implicated in a case of Ciguatera
Ciguatera
Ciguatera is a foodborne illness caused by eating certain reef fishes whose flesh is contaminated with toxins originally produced by dinoflagellates such as Gambierdiscus toxicus which lives in tropical and subtropical waters. These dinoflagellates adhere to coral, algae and seaweed, where they are...
poisoning. In Singapore
Singapore
Singapore , officially the Republic of Singapore, is a Southeast Asian city-state off the southern tip of the Malay Peninsula, north of the equator. An island country made up of 63 islands, it is separated from Malaysia by the Straits of Johor to its north and from Indonesia's Riau Islands by the...
, A. indica has successfully been bred in aquaculture
Aquaculture
Aquaculture, also known as aquafarming, is the farming of aquatic organisms such as fish, crustaceans, molluscs and aquatic plants. Aquaculture involves cultivating freshwater and saltwater populations under controlled conditions, and can be contrasted with commercial fishing, which is the...
for food production in relatively low numbers. Juveniles are occasionally used in saltwater aquariums, noted for their filamentous anal and dorsal fins.