{{short description|Species of fish}} {{Speciesbox | image =Cleftbelly trevally 2.jpg | status = LC | status_system = IUCN3.1 | status_ref = <ref name="iucn status 20 November 2021">{{cite iucn |author=Smith-Vaniz, W.F. |author2=Borsa, P. |author3=Carpenter, K.E. |author4=Jiddawi, N. |author5=Yahya, S. |author6=Obota, C. |date=2018 |title=''Atropus atropos'' |volume=2018 |article-number=e.T20256645A46664034 |doi=10.2305/IUCN.UK.2018-2.RLTS.T20256645A46664034.en |access-date=20 November 2021}}</ref> | parent_authority = [[Lorenz Oken|Oken]], 1817 | display_parents = 3 | taxon = Atropus atropos | authority = ([[Marcus Elieser Bloch|Bloch]] & [[Johann Gottlob Schneider|Schneider]], 1801) | synonyms = * ''Brama atropos'', <br /><small>Bloch & Schneider, 1801</small> * ''Caranx atropus'', <br /><small>(Bloch & Schneider, 1801)</small> * ''Atropus atropus'' <small>(misspelling)</small> | range_map = Atropus atropos distribution.png | range_map_caption = Approximate range of the cleftbelly trevally }} The '''cleftbelly trevally''' ('''''Atropus atropos'''''), also known as the '''cleftbelly kingfish''', '''Kuweh trevally''' or '''thin crevalle''', is a species of [[tropical fish|tropical]] [[marine biology|marine]] [[fish]] of the jack family, [[Carangidae]]. The species inhabits coastal waters throughout the [[Indian Ocean|Indo]]-[[West Pacific]] region from [[South Africa]] in the west to [[Japan]] in the east, often found near the water's surface. The cleftbelly trevally is distinguished by a number of anatomical characteristics, with a deep median groove in the belly giving the species its [[common name]]. It is not a large fish, growing to a maximum recorded length of {{cvt|26.5|cm}}. Cleftbelly trevally are [[predation|predatory]] fish, taking a variety of small [[crustacean]]s and fish. The species is of minor importance to [[fishery|fisheries]] throughout its range.
==Taxonomy and naming== The cleftbelly trevally was formerly the only species in the [[genus]] ''Atropus'', which is one of 31 genera in the jack [[Family (taxonomy)|family]], [[Carangidae]]. The Carangidae are part of the [[Order (biology)|order]] [[Carangiformes]].<ref name = Nelson5>{{BioRef |fotw5 |pages=380–387}}</ref>
The species was first [[Scientific classification|scientifically described]] under the name of ''Brama atropos'' by [[German people|German]] [[ichthyologist]]s [[Marcus Elieser Bloch]] and [[Johann Gottlob Schneider]] in the massive 1801 volume of ''Systema Ichthyologiae iconibus cx illustratum'', a document which is the [[Taxonomy (biology)|taxonomic]] authority for many species.<ref name = "fishbase">{{FishBase |Atropus|atropos | year = 2007 | month = November}}</ref> Bloch and Schneider placed the species in the genus ''[[Brama (fish)|Brama]]'', within the [[pomfret]] family. The generic position of the species was revised twice, once being placed in the jack genus, ''[[Caranx]]'', and finally into ''Atropus''. The genus ''Atropus'' had been informally created by [[Georges Cuvier]] in 1817 as "Les Atropus", and was formally [[Latinisation (literature)|Latinized]] by [[Lorenz Oken]], thus making him the author of the genus.<ref name = "Lin1999">{{cite journal | last = Lin | first = Pai-Lei | author2 = Shao, Kwang-Tsao | title = A Review of the Carangid Fishes (Family Carangidae) From Taiwan with Descriptions of Four New Records | journal = Zoological Studies | volume = 38 | issue = 1 | pages = 33–68 | url = http://cat.inist.fr/?aModele=afficheN&cpsidt=10055944 | date = 18 April 1999 | access-date = 1 January 2008 | archive-date = 29 February 2012 | archive-url = https://web.archive.org/web/20120229173915/http://cat.inist.fr/?aModele=afficheN&cpsidt=10055944 }}</ref> ''A. atropos'' is the [[type species]] of the genus by [[monotypy]]. The [[type specimen]] was taken from the waters of [[Puducherry (city)|Puducherry]], in [[India]].
The fact that the generic and specific names differ by a single letter has also led to the misspelling of the species as ''Atropus atropus'' in some publications.<ref name = "Lin1999"/> The species is most commonly referred to in English as the cleftbelly trevally, with other names including cleftbelly kingfish, Kuweh trevally and thin crevalle.<ref name = "fishbase"/> It is also occasionally called the 'blackfin jack', but should not be confused with ''[[Hemicaranx zelotes]]'', also known by that name.
==Description== [[File:Atropus atropos.png|thumb|200 px|left|Male cleftbelly trevally]]The cleftbelly trevally has a body shape similar in many ways to a number of the larger jacks, with a strongly compressed body almost [[Glossary of ichthyology#O|ovate]] in shape.<ref name = "FAO">{{cite book | editor-last = Carpenter | editor-first = Kent E. | editor2-first = Volker H. |editor2-last=Niem | title = FAO species identification guide for fishery purposes. The living marine resources of the Western Central Pacific. Volume 5. Bony fishes part 3 (Menidae to Pomacentridae) | publisher = FAO | year = 2001 | location = Rome | page = 2684 | url = ftp://ftp.fao.org/docrep/fao/009/y4160e/y4160e00.pdf | isbn = 92-5-104587-9 }}</ref> The [[Anatomical terms of location#Dorsal and ventral|dorsal]] profile of the head is straight and steep from the tip of the upper [[jaw]] to above the eye where the profile becomes [[wikt:convex|convex]]. The eye lacks an [[adipose eyelid]], and the upper jaw has a narrow band of small teeth, while the lower jaw has two or three rows of small teeth which narrow to one row on the sides of the jaw.<ref name = "FAO"/> The [[Anatomical terms of location#Dorsal and ventral|ventral]] profile is [[wiktionary:Concave|concave]] upwards, with a major distinguishing feature of the species being a deep median groove along the belly, into which the large [[pelvic fin]]s fold, also encompassing the first two [[anal fin]] [[Fish anatomy#Spines and rays|spines]] and [[anus]]. The entire chest from underneath the [[pectoral fin]]s to the base of the pelvic fins is scaleless.<ref name = "Lin1999"/> There are two separate [[dorsal fin]]s, the first with eight spines and the second with a single spine followed by 19 to 22 [[Fish anatomy#Spines and rays|soft rays]].<ref name = "Oman">{{cite book | last = Randall | first = John E. | title = Coastal Fishes of Oman | publisher = University of Hawaii Press | year = 1995 | location = Honolulu | page = 183 | isbn = 0-8248-1808-3 }}</ref> The anal fin has two detached spines before the major part of the anal fin, which consists of one spine and 17 or 18 soft rays. The pectoral and pelvic fins are both quite long, with the latter extending almost to the anal fin origin. The [[lateral line]] has a moderately strong arch [[Anatomical terms of location#Anterior and posterior|anteriorally]] which intersects the straight section underneath the fifth to seventh dorsal rays. The straight part of the lateral line has 31–37 [[scute]]s.<ref name = "Oman"/>[[File:Cleftbelly trevally.jpg|right|thumb|210px|A cleftbelly trevally at an Indian market]] There are 24 [[vertebra]]e and 29 to 34 total [[gill raker]]s.<ref name = "FAO"/> The species is known to reach {{cvt|26.5|cm}} in length, although often encountered below {{cvt|20|cm}}.<ref name = "fishbase"/>
The cleftbelly trevally is a bluish green on the upper body which fades to silver on the underside of the fish. The membranes of the large pelvic fin are a distinctive black, while the remaining fins are a pale white colour. Juveniles have indistinct dark bands across their bodies, with a black spot becoming more prominent in adults.<ref name = "Oman"/>
The species show [[sexual dimorphism]] in their dorsal fins, with mature males having between 6 and 12 elongated soft rays, strung out into filaments of varying lengths. The anal fin is also has five similar extensions of the soft rays. Females do not show this elongation.<ref>{{cite journal | last = Shameen | first = A. |author2=Dutt, S. | title = A note on sexual dimorphism in carangid fishes | journal = Mahasagar | volume = 17 | issue = 3 | pages = 179–181 | year = 1984 | issn = 0542-0938 }}</ref>
==Distribution and habitat== The cleftbelly trevally inhabits the [[tropics|tropical]] and [[subtropical]] waters of the [[Indian Ocean|Indo]]-[[West Pacific]] region. Its range extends from [[South Africa]]<ref name = "F1">{{cite journal | last = Fowler | first = Henry W. | title = South African Fishes Received from Mr. H. W. Bell-Marley in 1935 | journal = Proceedings of the Academy of Natural Sciences of Philadelphia | volume = 87| pages = 361–408| year = 1935}}</ref> along the [[east Africa]]n coast<ref name = "F2">{{cite journal | last = Fowler | first = Henry W. | title = Fishes Obtained by Mr. H. W. Bell-Marley Chiefly in Natal and Zululand in 1929 to 1932 | journal = Proceedings of the Academy of Natural Sciences of Philadelphia | volume = 86 | pages = 405–514 | year = 1934 }}</ref> including the [[Persian Gulf]], east to [[India]], [[Southeast Asia]], the [[Philippines]], [[Taiwan]] and southern [[Japan]].<ref name = "FAO"/> Some sources state the Persian Gulf as the westernmost point of the species range, but specimens sent to [[Henry Weed Fowler|Henry Fowler]] from South and eastern Africa in the 1930s show this to be incorrect.<ref name = "F1"/><ref name = "F2"/>
The species inhabit shallow [[coastal]] waters, where they swim close to the surface. There has been a report of the species living in areas near [[estuary|estuaries]] which empty large flows of fresh water into these areas, indicating the species may be able to live in estuarine environments.<ref>{{cite journal | last1 = Ansari | first1 = Z.A. | first2 = A. |last2=Chatterji |first3=B. S. |last3=Ingole | title = Community Structure and Seasonal Variation of an Inshore Demersal Fish Community at Goa, West Coast of India | journal = [[Estuarine, Coastal and Shelf Science]] | volume = 41 | issue = 5 | pages = 593–610 | publisher = Elsevier | year = 1995 | doi = 10.1016/0272-7714(95)90029-2| bibcode = 1995ECSS...41..593A |display-authors=etal}}</ref>
==Biology and fishery== The cleftbelly trevally is a [[predation|predatory]] species, preying on small [[crustacean]]s including [[shrimp]]s, [[copepod]]s and [[Decapoda|decapods]], as well as small fish.<ref>{{cite book | last1 = Masuda | first1 = H. |first2=K. | last2 = Amaoka |first3=C. |last3=Araga |first4=T. |last4=Uyeno |first5=T. |last5=Yoshino | title = The fishes of the Japanese Archipelago. Vol. 1 | publisher = Tokai University Press | year = 1984 | location = Tokyo, Japan | page = 437 | isbn = 978-4-486-05054-4 }}</ref> Reproduction in the species has not been extensively studied, although early growth has been described in a 1984 article. The study was located in India, and showed the fish grows {{cvt|12.4|cm}} in its first year of life, growing slower in its second and third years, adding {{cvt|7.35|cm}} and {{cvt|3.5|cm}} to its total length, respectively, in these years.<ref>{{cite journal | last = Kochar | first = L.S. |author2=S.N. Dwivedi | title = A Comparative study of Morphometric Relationships and Age and Growth of ''Atropus atropus'' and ''Carangoides malabaricus'' Bloch and Schneider off Bombay Coast India | journal = Proceedings of the National Academy of Sciences, India Section B | volume = 58 | issue = 4 | pages = 515–524 | year = 1988 | issn = 0369-8211 }}</ref> The species reaches [[sexual maturity]] at {{cvt|21|cm}}, in the second or third year of its life.<ref>{{cite journal | last1 = Reuben | first1 = S. | first2 = H.M. |last2=Kasim |first3=S. |last3=Sivakami | title = Fishery, biology and stock assessment of carangid resources from the Indian seas | journal = Indian Journal of Fisheries | volume = 39 | issue = 3–4 | pages = 195–234 | year = 1992 |display-authors=etal}}</ref>
The species is of minor importance to [[fishery|fisheries]] throughout its range, taken mainly by [[trawl]]s, traps and by various hook-and-line methods.<ref name = "FAO"/>
==References== {{Reflist|2}}
{{Portal bar|Fish}} {{Taxonbar|from=Q3235117}}
[[Category:Caranginae|cleftbelly trevally}]] [[Category:Fish of the Indian Ocean]] [[Category:Fish of the Pacific Ocean]] [[Category:Marine fish of East Africa]] [[Category:Marine fish of Asia]] [[Category:Fish of the Red Sea]] [[Category:Fish of South Asia]] [[Category:Fish of Southeast Asia]] [[Category:Fish described in 1801|cleftbelly trevally]] [[Category:Taxa named by Marcus Elieser Bloch]] [[Category:Taxa named by Johann Gottlob Theaenus Schneider]]