The longfin crevalle jack (''Caranx fischeri'') is a recently described

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 ...

of large marine fish classified in the jack

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 ...

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 ...

. It inhabits the subtropical waters of the east

Atlantic Ocean The Atlantic Ocean is the second-largest of the world's five oceans, with an area of about . It covers approximately 20% of Earth's surface and about 29% of its water surface area. It is known to separate the " Old World" of Africa, Europe ...

, ranging along the

Africa Africa is the world's second-largest and second-most populous continent, after Asia in both cases. At about 30.3 million km2 (11.7 million square miles) including adjacent islands, it covers 6% of Earth's total surface area ...

n coast from Mauritania south at least to Moçamedes in southern

Angola , national_anthem = " Angola Avante"() , image_map = , map_caption = , capital = Luanda , religion = , religion_year = 2020 , religion_ref = , coordina ...

, with the species historically present in the

Mediterranean Sea The Mediterranean Sea is a sea connected to the Atlantic Ocean, surrounded by the Mediterranean Basin and almost completely enclosed by land: on the north by Western and Southern Europe and Anatolia, on the south by North Africa, and on the ...

. It is an inshore species, known to occasionally penetrate

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 ...

, possibly to

spawn Spawn or spawning may refer to: * Spawn (biology), the eggs and sperm of aquatic animals Arts, entertainment, and media * Spawn (character), a fictional character in the comic series of the same name and in the associated franchise ** '' Spawn: ...

. The species is very similar to the

crevalle jack The crevalle jack (''Caranx hippos''), also known as the common jack, black-tailed trevally, couvalli jack, black cavalli, jack crevale, or yellow cavalli is a common species of large marine fish classified within the jack family, Carangidae. The ...

, ''Caranx hippos'', and is separated by its extended

dorsal Dorsal (from Latin ''dorsum'' ‘back’) may refer to: * Dorsal (anatomy), an anatomical term of location referring to the back or upper side of an organism or parts of an organism * Dorsal, positioned on top of an aircraft's fuselage * Dorsal c ...

and anal fin lobes as well as more detailed anatomical features including dorsal and anal fin ray counts. The fish is known to reach 127 cm in length and 20.9 kg in weight. The longfin crevalle jack is a

predator Predation is a biological interaction where one organism, the predator, kills and eats another organism, its prey. It is one of a family of common feeding behaviours that includes parasitism and micropredation (which usually do not kill th ...

y fish, taking small fish as its main prey. Due to longstanding confusion between ''C. fischeri'' and ''C. hippos'', the importance of each species to African fisheries is poorly understood, with a known combined catch in this region of between 2,233 and 10,054

tonne The tonne ( or ; symbol: t) is a unit of mass equal to 1000 kilograms. It is a non-SI unit accepted for use with SI. It is also referred to as a metric ton to distinguish it from the non-metric units of the short ton ( United State ...

s per year in 1995–2004. Like its close relatives, the species is considered a powerful

gamefish Game fish, sport fish or quarry refer to popular fish pursued by recreational anglers, and can be freshwater or saltwater fish. Game fish can be eaten after being caught, or released after capture. Some game fish are also targeted commercia ...

and highly sought after, although their coarse flesh makes for relatively poor quality food.

Taxonomy and naming

The longfin crevalle jack is classified within the genus ''

Caranx ''Caranx'' is a genus of tropical to subtropical marine fishes in the jack family Carangidae, commonly known as jacks, trevallies and kingfishes. They are moderate- to large-sized, deep-bodied fishes which are distinguished from other carangid g ...

'', one of a number of groups known as the jacks or trevallies. ''Caranx'' itself is part of the larger jack and horse mackerel family

, part of the order

Carangiformes Carangiformes is an order of the ray-finned fishes. The order is part of a clade which is a sister clade to the Ovalentaria, the other orders in the clade being Synbranchiformes, Anabantiformes, Istiophoriformes and Pleuronectiformes. The Caran ...

. The species belongs to the "''Caranx hippos'' complex" as defined by William Smith-Vaniz and Kent Carpenter, which includes ''C. fischeri'', ''C. hippos'' and '' C. caninus''. The identity of the species was entangled with ''C. hippos'' until William Smith-Vaniz and Ken Carpenter described the species in full in 2007, anatomically setting it aside from ''C. hippos''. The

holotype A holotype is a single physical example (or illustration) of an organism, known to have been used when the species (or lower-ranked taxon) was formally described. It is either the single such physical example (or illustration) or one of sever ...

specimen is derived from a specimen collected in 1978 off

Cameroon Cameroon (; french: Cameroun, ff, Kamerun), officially the Republic of Cameroon (french: République du Cameroun, links=no), is a country in west-central Africa. It is bordered by Nigeria to the west and north; Chad to the northeast; the C ...

, and was initially referred to ''C. hippos''. The species has no synonyms due to its recent description, but the species has been misidentified as both ''C. hippos'' and ''C. carangus'' (now synonymous with ''C. hippos''). The specific epithet is in reference to Dr. Walter Fischer, a former official of the

FAO The Food and Agriculture Organization of the United Nations (FAO)french: link=no, Organisation des Nations unies pour l'alimentation et l'agriculture; it, Organizzazione delle Nazioni Unite per l'Alimentazione e l'Agricoltura is an intern ...

who initiated the Species Identification and Data Program. The naming of the new species was presented at an IGCC and FAO meeting. The species common name as defined by Smith-Vaniz and Carpenter is 'longfin crevalle jack', referring to the extended fin lobes which separates the species from the crevalle jack.

Description

The longfin crevalle jack is large species, growing to a maximum recorded size of 53 cm as measured by Smith-Vaniz and Carpenter in their description. Discussion on the

angling Angling is a fishing technique that uses a fish hook or "angle" (from Old English ''angol'') attached to a fishing line to tether individual fish in the mouth. The fishing line is usually manipulated via a fishing rod, although rodless techni ...

merits of the species in the same publication indicate that the species grows significantly larger, recorded up to 127 cm by anglers mistaking it for ''C. hippos''. It has a body profile similar to most of the large species in ''Caranx'', possessing a strongly compressed approximately

oblong An oblong is a non-square rectangle. Oblong may also refer to: Places * Oblong, Illinois, a village in the United States * Oblong Township, Crawford County, Illinois, United States * A strip of land on the New York-Connecticut border in the Unit ...

form. The

profile is much more

convex Convex or convexity may refer to: Science and technology * Convex lens, in optics Mathematics * Convex set, containing the whole line segment that joins points ** Convex polygon, a polygon which encloses a convex set of points ** Convex polytop ...

than the

ventral Standard anatomical terms of location are used to unambiguously describe the anatomy of animals, including humans. The terms, typically derived from Latin or Greek roots, describe something in its standard anatomical position. This position prov ...

profile, with the caudal peduncle quite slender. The

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 ...

is in two parts, the first consisting of 8 spines and the second of 1 spine followed by 21 to 24

soft rays Fish anatomy is the study of the form or morphology of fish. It can be contrasted with fish physiology, which is the study of how the component parts of fish function together in the living fish. In practice, fish anatomy and fish physiology co ...

. The dorsal and anal fin lobes are slightly elongated on the species, which distinguishes from the similar

. The anal fin consists of 2 detached spines anterior to the main bulk of the fin, which consists of 1 spine followed by 17 to 19 soft rays. The lateral line is moderately arched anteriorly, with this section containing 50 to 73 scales, while the straight section has 0 to 16 scales and 24 to 41

scute A scute or scutum (Latin: ''scutum''; plural: ''scuta'' "shield") is a bony external plate or scale overlaid with horn, as on the shell of a turtle, the skin of crocodilians, and the feet of birds. The term is also used to describe the anterior po ...

s. The breast is devoid of scales up to the origin of the pelvic fins and is separated from the base of the

pectoral fin 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 ...

s by a narrow band of scales. there are 20 to 25

gill raker Gill rakers in fish are bony or cartilaginous processes that project from the branchial arch (gill arch) and are involved with suspension feeding tiny prey. They are not to be confused with the gill filaments that compose the fleshy part of the ...

s in total and 24

vertebrae The spinal column, a defining synapomorphy shared by nearly all vertebrates, Hagfish are believed to have secondarily lost their spinal column is a moderately flexible series of vertebrae (singular vertebra), each constituting a characteristi ...

. The longfin crevalle jack is olive to greenish blue in colour dorsally, fading to pale and white ventrally. The dorsal fin dark brown to grey while the anal fin is brownish yellow, becoming white towards the lobe. The

caudal fin 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 ...

is brown-yellow and the pelvic fins white. The species has a dark spot both on its

opercle The operculum is a series of bones found in bony fish and chimaeras that serves as a facial support structure and a protective covering for the gills; it is also used for respiration and feeding. Anatomy The opercular series contains four b ...

and lower pectoral fin rays.

Distribution and habitat

The longfin crevalle jack inhabits the subtropical waters of the east

, currently known to range from Mauritania south to at least Moçamedes in southern

Angola , national_anthem = " Angola Avante"() , image_map = , map_caption = , capital = Luanda , religion = , religion_year = 2020 , religion_ref = , coordina ...

. Publications describing historical fish specimens collected in the

Mediterranean The Mediterranean Sea is a sea connected to the Atlantic Ocean, surrounded by the Mediterranean Basin and almost completely enclosed by land: on the north by Western Europe, Western and Southern Europe and Anatolia, on the south by North Africa ...

confirm ''Caranx fischeri'' was present in this region, although no recent specimens are known. The species appears to be able to travel long distances, with one adult collected from Ascension Island in the mid-Atlantic. The longfin crevalle jack appears to be primarily an inshore species based the limited data available, although captures such as those in the Ascension Island indicate the species may live

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 ...

ally. In the inshore environment they are known from

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, as well as estuarine environments, possibly penetrating the upper reaches of

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 ...

Habitat and behavior

The specifics of the longfin crevalle jack's biology are not known due its recent description and previous confusion with ''C. hippos''. It is clear that all species of crevalle jack are powerful

s, taking a variety of small, schooling fish species including herrings, other carangids and

porgies The Sparidae are a family of fish in the order Perciformes, commonly called sea breams and porgies. The sheepshead, scup, and red seabream are species in this family. Most sparids are deep-bodied compressed fish with a small mouth separated by a ...

of the family Sparidae. Small jacks, probably including ''C. fischeri'' also are known to take invertebrates including

shrimps Shrimp are crustaceans (a form of shellfish) with elongated bodies and a primarily swimming mode of locomotion – most commonly Caridea and Dendrobranchiata of the decapod order, although some crustaceans outside of this order are refer ...

and crabs. Reproduction is poorly known, with

spawning Spawn is the eggs and sperm released or deposited into water by aquatic animals. As a verb, ''to spawn'' refers to the process of releasing the eggs and sperm, and the act of both sexes is called spawning. Most aquatic animals, except for aquat ...

possibly occurring in estuaries and rivers.

Relationship with humans

Due to confusion with ''C. hippos'', the species contribution to fisheries is also poorly understood. A combined total of 2233 to 10054 t per year for ''C. hippos'' and ''C. fischeri'' was recorded from several

n countries by the FAO in the 1995 to 2004 interval, indicating it is of moderate importance. Like the other crevalle jacks, the species is a strong

and sought after by anglers in West Africa. Taken by lures or bait, the species is not considered a good

table fish Many species of fish are caught by humans and consumed as food in virtually all regions around the world. Fish has been an important dietary source of protein and other nutrients throughout human history. The English language does not have ...

, having coarse, tasteless flesh. The

IGFA The International Game Fish Association (''IGFA'') is the leading authority on angling pursuits and the keeper of the most current World Record fishing catches by fish categories. Fishermen who are sport fishers are careful to follow their strin ...

world record stands at 28 kg (61 lb 12 oz) caught off the Loos Islands, Guinea by Daniel Gaillard in 2017, previous records were caught in

Angola , national_anthem = " Angola Avante"() , image_map = , map_caption = , capital = Luanda , religion = , religion_year = 2020 , religion_ref = , coordina ...

References

External links

Longfin crevalle jack at FishbaseEncyclopedia of Life page
{{Taxonbar, from=Q5258089 longfin crevalle jack Fish of the East Atlantic Marine fauna of West Africa longfin crevalle jack