# African threadfish > Mediated Wiki article. Canonical URL: https://mediated.wiki/source/African_threadfish > Markdown URL: https://mediated.wiki/source/African_threadfish.md > Source: https://en.wikipedia.org/wiki/African_threadfish > Source revision: 1354736750 > License: Creative Commons Attribution-ShareAlike 4.0 International (https://creativecommons.org/licenses/by-sa/4.0/) {{Short description|Species of fish}} {{Speciesbox | status = LC | status_system = IUCN3.1 | status_ref = {{cite iucn |author=Smith-Vaniz, W.F. |author2=Carpenter, K.E. |date=2015 |title=''Alectis alexandrina'' |volume=2015 |article-number=e.T198772A43071024 |doi=10.2305/IUCN.UK.2015-4.RLTS.T198772A43071024.en |access-date=20 November 2021}} | image = Alectis-alexandrina.JPG | taxon = Alectis alexandrina | authority = ([É. Geoffroy Saint-Hilaire](/source/%C3%89tienne_Geoffroy_Saint-Hilaire), 1817) | synonyms = *''Gallus alexandrinus''
Geoffroy Saint-Hilaire, 1817 *''Scyris alexandrina''
(Geoffroy Saint-Hilaire, 1817) *''Scyris alexandrinus''
(Geoffroy Saint-Hilaire, 1817) *''Vomer alexandrinus''
(Geoffroy Saint-Hilaire, 1817) *''Caranx alexandrinus''
(Geoffroy Saint-Hilaire, 1817) *''Blepharis alexandrinus''
(Geoffroy Saint-Hilaire, 1817) *''Alectis alexandrinus''
(Geoffroy Saint-Hilaire, 1817) *''Gallichthys aegyptiacus'' ([Cuvier](/source/Georges_Cuvier), 1833) *''Caranx goreensis'' (Cuvier, 1833) *''Hynnis goreensis'' (Cuvier, 1833) *''Selene goreensis'' (Cuvier, 1833) | range_map = Alectis alexandrinus distribution.PNG | range_map_caption =Approximate distribution of the African threadfish. Note there is only one record for the Adriatic Sea. }} The '''African threadfish''' (''Alectis alexandrina''), also known as the '''Alexandria pompano''', is a [species](/source/species) of large [marine](/source/marine_(ocean)) [fish](/source/fish) in the jack family, [Carangidae](/source/Carangidae). The species is distributed along the coast of tropical [Africa](/source/Africa) in the eastern [Atlantic Ocean](/source/Atlantic_Ocean), extending to the [Mediterranean Sea](/source/Mediterranean_Sea). Adults live predominantly in waters shallower than 70 m deep, often forming small schools. The African threadfish is similar in appearance to the closely related and co-occurring [African pompano](/source/African_pompano), with the species' most definitive feature its slightly concave head profile. Like other members of the genus ''[Alectis](/source/Alectis)'', the juveniles of the species have long trailing dorsal and anal [fin](/source/fin)s. The African threadfish is of minor [commercial importance](/source/fishery), and is also considered to be a [game fish](/source/game_fish). ==Taxonomy and naming== The African threadfish is one of three members of the diamond trevally [genus](/source/genus) ''[Alectis](/source/Alectis)'', which is one of 33 genera in the jack and horse mackerel [family](/source/Family_(taxonomy)) [Carangidae](/source/Carangidae). The Carangidae are part of the [order](/source/Order_(biology)) [Carangiformes](/source/Carangiformes).{{cite book |title=Fishes of the World |edition=5th |author1=J. S. Nelson |author2=T. C. Grande |author3=M. V. H. Wilson |year=2016 |pages=380–387 |publisher=Wiley |ISBN=978-1-118-34233-6 |url=https://sites.google.com/site/fotw5th/ |access-date=2019-11-23 |archive-date=2019-04-08 |archive-url=https://web.archive.org/web/20190408194051/https://sites.google.com/site/fotw5th/ }} The species has a complex [taxonomic history](/source/Taxonomy_(biology)), featuring two [species description](/source/species_description)s. The first description was made by the [French](/source/France) [naturalist](/source/naturalist) [Étienne Geoffroy Saint-Hilaire](/source/%C3%89tienne_Geoffroy_Saint-Hilaire) in 1817, in which he named the species ''Gallus alexandrinus'', using the generic name ''[Gallus](/source/Gallus_(bird))'' which had been created by [Lacépède](/source/Bernard_Germain_%C3%89tienne_de_la_Ville%2C_Comte_de_Lac%C3%A9p%C3%A8de) after he recognised the genus distinct from ''Zeus'', a genus of [dories](/source/List_of_fishes_known_as_dory). However, ''Gallus'' was preoccupied by a bird,{{cite book | last = Hosese | first = D.F. |author2= Bray, D.J. |author3=Paxton, J.R. |author4= Alen, G.R. | title = Zoological Catalogue of Australia Vol. 35 (2) Fishes | publisher = CSIRO | year = 2007 | location = Sydney | page = 1150 | isbn =978-0-643-09334-8 }} leading to the reassignment of the species to at least six different genera, before the species was placed in ''Alectis''. The second description was made by [Georges Cuvier](/source/Georges_Cuvier) in 1833 under the name of ''Gallichthys aegyptiacus''. This name was also re-evaluated twice, before the description was discarded as a junior synonym of ''A. alexandrina''. The species has also been incorrectly referred to as ''Alectis alexandrinus''. However the genus is feminine and so ''alexandrina'' is the correct spelling. The common names 'African threadfish' and 'Alexandria pompano' are in reference to the species prominent distribution around Africa, as well as the thread like appearance of the [juvenile](/source/juvenile_(organism))s dorsal and anal fins.{{FishBase | genus = Alectis | species = alexandrina | year = 2021 | month = February}} ==Description== thumb|left|African threadfish have a slight concavity to their forehead profileThe African threadfish has the typical [body](/source/Anatomy) structure of a large jack, with a distinctly angular, strongly compressed body. The major identifying feature of the species is its head profile, having a slight concavity near the [eye](/source/eye)s which distinguishes it from the [African pompano](/source/African_pompano). The [dorsal](/source/Anatomical_terms_of_location) profile of the fish is more curved than the [ventral](/source/Anatomical_terms_of_location) profile, and the body is deepest between the origins of the soft [dorsal](/source/dorsal_fin) and soft [anal fin](/source/anal_fin)s.{{cite journal | last = Gunn | first = John S. | title = A revision of selected genera of the family Carangidae (Pisces) from Australian waters | journal = Records of the Australian Museum | volume = Supplement 12 | pages =1–78 | year = 1990 | doi=10.3853/j.0812-7387.12.1990.92| url = https://australianmuseum.net.au/Uploads/Journals/17723/92.pdf }} The first section of the dorsal fin consists of 5 to 7 visible [spines](/source/Fish_anatomy), with the second section having one spine and 20 to 22 [soft rays](/source/Fish_anatomy). The anal fin has two spines followed by a single spine and 18 or 19 soft rays. The [pectoral fin](/source/pectoral_fin) is long and curved, extending beyond the junction of the straight and curved sections of the [lateral line](/source/lateral_line). Anterior to the [caudal fin](/source/caudal_fin) are two oblate keels on each side of the line of scutes.{{cite book | last = Bellemans | first = M |author2=A. Sagna|author3=W. Fischer|author4=N. Scialabba | title = Guide des Ressources Halieutiques Du Senegal et de la Gambie | publisher = FAO | year = 1988 | location = Rome | page = 45 | isbn = 92-5-202747-5}} The body appears to be scaleless, but on closer inspection has minute, deeply embedded [scales](/source/scale_(zoology)). The lateral line is strongly curved anteriorly, with a section of 6 to 11 [scute](/source/scute)s toward the tail. Juveniles and often adults have long, filamentous trailing first anal and dorsal fin spines, a trait of all members of ''Alectis''. The species grows to at least 1 m in length. The African threadfish is silver in colour, often with blue and greenish tints and reflection, especially when fresh. The fins are all a pale silvery green to blue colour, or [hyaline](/source/hyaline). Juveniles may show two dark bands on their lower bodies. ==Distribution and habitat== The African threadfish is primarily distributed throughout the tropical eastern [Atlantic Ocean](/source/Atlantic_Ocean), inhabiting the waters of [West Africa](/source/West_Africa) from [Morocco](/source/Morocco) around to [Angola](/source/Angola). The species also has had several individuals taken from the [Mediterranean](/source/Mediterranean){{cite journal | last = Torcu | first = Hatic | author2 = Zeliha Aka | author3 = Akif İşbilir | title = An investigation on fishes of the Turkish Republic of Northern Cyprus | journal = Turkish Journal of Veterinary and Animal Sciences | volume = 25 | issue = 2 | pages = 155–159 | year = 2001 | url = http://journals.tubitak.gov.tr/veterinary/issues/vet-01-25-2/vet-25-2-3-9909-13.pdf | access-date = 2007-10-31 | archive-date = 2021-05-14 | archive-url = https://web.archive.org/web/20210514055928/https://journals.tubitak.gov.tr/veterinary/issues/vet-01-25-2/vet-25-2-3-9909-13.pdf }}{{cite journal| last = Santos | first =R.S. | author2 = Barreiros, J.P. |author3=Worms, J. |author4=Porteiro, F.M. |author5=Afonso, P. |author6=Wirtz, P. | title = Contribution to the knowledge of the coastal marine fishes of São Tomé Island (Gulf of Guinea) | journal = Life and Marine Sciences | volume = 17 | issue = A | pages = 65–92 | year = 1999 | hdl = 1834/704}} and one extreme capture in the [Adriatic Sea](/source/Adriatic_Sea).{{cite journal | last = Dulcic | first = J. | title = On the record of the African threadfish ''Alectis alexandrinus'' (Pisces: Carangidae) from the Adriatic Sea | journal = [Journal of the Marine Biological Association of the United Kingdom](/source/Journal_of_the_Marine_Biological_Association_of_the_United_Kingdom) | volume = 85 | issue = 4 | pages = 1013–1014 | year = 2005 | doi = 10.1017/S0025315405012051}} Adults are generally solitary in [coastal](/source/coastal) waters, occupying lower parts of the water column, down to at least 70 m. Juveniles are usually [pelagic](/source/pelagic) and drift with ocean currents, sometimes ending up in [estuarine](/source/estuarine) environments. ==Biology== Limited information is available on the species [biology](/source/biology), with only the [diet](/source/Diet_(nutrition)) of the species confirmed. The African threadfish feeds on [squid](/source/squid) and other fishes. The [reproduction](/source/reproduction) in the species is largely unknown, but observations on ''Alectis ciliaris'' suggest individual fish may pair and then [spawn](/source/spawn_(biology)).{{cite journal | last = von Westernhagen | first = H. | title = Observations on the natural spawning of ''Alectis indicus'' (Rüppell) and ''Caranx ignobilis'' (Forsk.) (Carangidae) | journal = Journal of Fish Biology | volume = 6 | issue = 4 | pages = 513–516 | year = 1974 | doi = 10.1111/j.1095-8649.1974.tb04567.x}} ==Relationship to humans== [[File:African threadfish Ghana 2.jpg|thumb|African threadfish taken off [Ghana](/source/Ghana)]] The species is of minor importance to local [fisheries](/source/fisheries) throughout its range, and is also considered a good [game fish](/source/game_fish), especially in larger sizes. The species is rarely targeted by anglers though, due to its comparative rarity. The fish also fetches high prices at [market](/source/Market_(economics)), unlike many other members of the Carangidae. The [IGFA](/source/IGFA) world record for the species stands at {{convert|8.10|kg|lboz|abbr=on}} caught off of Daklha, [Morocco](/source/Morocco) in 1993.{{cite web |title=Threadfish, African |url=https://igfa.org/igfa-world-records-search/?search_type=CommonName&search_term_1=Threadfish,%20African |website=igfa.org |publisher=IGFA |access-date=14 June 2019}} ==References== {{Reflist|30em}} ==External links== {{Commons}} *[http://eol.org/pages/343488/overview African threadfish (''Alectis alexandrina'')] at [http://eol.org Encyclopaedia of Life] {{Taxonbar|from=Q765602}} African threadfish Category:Fish of Africa Category:Fish of the East Atlantic Category:Fish of the Mediterranean Sea Category:Marine fish of West Africa African threadfish Category:Taxa named by Étienne Geoffroy Saint-Hilaire --- Adapted from the Wikipedia article [African threadfish](https://en.wikipedia.org/wiki/African_threadfish) by Wikipedia contributors ([contributor history](https://en.wikipedia.org/wiki/African_threadfish?action=history)). Available under [Creative Commons Attribution-ShareAlike 4.0 International](https://creativecommons.org/licenses/by-sa/4.0/). Changes may have been made.