| Trachurus delagoa | |
|---|---|
Scientific classification  | |
| Domain: | Eukaryota |
| Kingdom: | Animalia |
| Phylum: | Chordata |
| Class: | Actinopterygii |
| Order: | Carangiformes |
| Family: | Carangidae |
| Genus: | Trachurus |
| Species: | T. delagoa |
| Binomial name | |
| Trachurus delagoa Nekrasov, 1970 | |
| Synonyms [2] | |
Trachurus delagoa, the African scad, is a species of jack mackerel from the family Carangidae which is found in the south western Indian Ocean. [2]
Trachurus delagoa has an elongate body which is slightly compressed and has the upper and lower profiles roughly the same. The eye is moderately large and has a well-developed adipose eyelid which normally covers almost all of the eye apart from a vertical oval with the pupil in the centre. It has a reasonably wide upper jaw which extends to underneath the forward anterior edge of the eye. The mouth is equipped with small teeth, having a single row in each jaw. It has two separate dorsal fins, the first having 8 spines with the second having a single spine and 28 to 32 soft rays. The anal fin has 2 detached spines to its front followed by a single spine and 24 to 28 soft rays. The pectoral fins are as long or longer than the length of the head. The scales in the lateral line and large and form scutes. It has a black spot on the upper margin of the operculum, the upper part of the body is dark blue and the flanks and belly are silvery. The anal and pectoral fins are pale yellow in colour, the caudal fin is grey and the pelvic fins are white or unpigmented. [3] It grows to a maximum total length of 35 centimetres (14 in). [2]
Trachurus delagoa occurs in the south-western Indian Ocean off the eastern costa of Africa from Eastern Cape Province to southern Mozambique. It is also found off southern Madagascar and the Walters Shoals. [1]
Trachurus delagoa is largely demersal and occurs in areas of the continental shelf where there is a sandy substrate. It ranges in depth from the shoreline to around 400 metres (1,300 ft). It spends the day in the depths and undertakes a vertical migration at night to feed near the surface. Its prey is made up largely of smaller fish and crustaceans. [3] It is a social species which forms schools. [1]
African scads are largely fished for with bottown trawls and with hook and line. [3] In KwaZulu Natal it is fished for on a small scale by fishermen on paddleboards or kayaks. [1]
The Atlantic horse mackerel, also known as the European horse mackerel or common scad, is a species of jack mackerel in the family Carangidae, which includes the jacks, pompanos and trevallies. It is found in the eastern Atlantic Ocean off Europe and Africa and into the south-eastern Indian Ocean. It is an important species in commercial fisheries and is listed as a Vulnerable species on The IUCN Red List of Threatened Species.
The Pacific jack mackerel, also known as the Californian jack mackerel or simply jack mackerel, is an abundant species of pelagic marine fish in the jack family, Carangidae. It is distributed along the western coast of North America, ranging from Alaska in the north to the Gulf of California in the south, inhabiting both offshore and inshore environments. The Pacific jack mackerel is a moderately large fish, growing to a maximum recorded length of 81 cm, although commonly seen below 55 cm. It is very similar in appearance to other members of its genus, Trachurus, especially T. murphyi, which was once thought to be a subspecies of T. symmetricus, and inhabits waters further south. Pacific jack mackerel travel in large schools, ranging up to 600 miles offshore and to depths of 400 m, generally moving through the upper part of the water column.
The bludger, also known as the bludger trevally, nakedbreast trevally or Bleeker's jackfish, is a widespread species of large marine fish in the jack family, Carangidae. The bludger inhabits the tropical and subtropical regions of the Indo-west Pacific Ocean, distributed from South Africa in the west to Japan and New Caledonia in the east. It is a large fish, growing to a maximum recorded length of 90 cm, and is very similar to the yellowspotted trevally, Carangoides fulvoguttatus, but can be separated by the complete absence of breast scales and a number of other anatomical features. The species inhabits moderately deep offshore coral and rocky reefs, where it preys on small crustaceans and fish. The reproductive biology of the species is poorly known, but it appears to move to more tropical waters to spawn. The bludger is of intermediate importance to fisheries throughout its range, taken by hook and line and various netting methods. It is of some value to anglers also, considered a good gamefish, but generally regarded as poor eating due to its soft oily flesh, which is used as bait by many anglers. The name ‘bludger’ is said to either refer to the blunt head of the species, or the destination of the fish when caught by professional fishermen who treat the fish as discard.
The Indian threadfish, also known as the Indian threadfin, diamond trevally, mirror fish or plumed trevally, 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. Adult fish tend to inhabit coastal waters over reefs down to 100 m in depth, while juveniles inhabit a variety of environments including estuaries and seagrass beds. The Indian threadfish is similar to the other two species in the genus Alectis, with a slight concavity in the profile of the head the most obvious distinguishing feature. It is a large species, growing to 165 cm and 25 kg in weight. The species is carnivorous, consuming fishes, cephalopods and crustaceans. The Indian threadfish is of minor commercial importance, and has been the subject of aquaculture in Singapore.
The cleftbelly trevally, also known as the cleftbelly kingfish, Kuweh trevally or thin crevalle, is a species of tropical marine fish of the jack family, Carangidae. The species inhabits coastal waters throughout the 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 the only member of the genus Atropus and 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 26.5 cm. Cleftbelly trevally are predatory fish, taking a variety of small crustaceans and fish. The species is of minor importance to fisheries throughout its range.
The horse-eye jack, also known as the big-eye jack, is a game fish and minor commercial fish in the family Carangidae. Its appearance is similar to that of the crevalle jack, although the horse-eye jack's head is not as blunt. The horse-eye jack is known to feed on smaller fish and on many invertebrates, such as shrimp and crab.
The yellowtail scad, is an abundant species of small inshore marine fish of the jack family, Carangidae. The species is widespread in the Indo-Pacific region from east Africa in the west to Hawaii in the east, extending north to Japan and south to Australia. The yellowtail scad is the only member of the monotypic genus Atule and is distinguished from similar species by a well-developed adipose eyelid and finlet-like extensions of the last rays of the dorsal and anal fins. It inhabits coastal areas such as bays and coral reefs, preying on small fishes and crustaceans. Spawning has been well studied in Hawaii, where fish enter bays to spawn, releasing up to 161,000 eggs each between March and October. The yellowtail scad is an important component of fisheries throughout its range, taken by a number of netting and hook-and-line methods. It is a prized food fish in some regions and is cooked or preserved by a variety of methods.
The longfin trevally, also known as the longfin kingfish, longfin cavalla or armed trevally, is a species of inshore marine fish in the jack family, Carangidae. The species is common in tropical to subtropical waters of the Indo-Pacific, ranging from South Africa in the west to Japan in the east, typically inhabiting inshore reefs and bays. The species is easily distinguished by its elongate dorsal and anal fin lobes and filamentous dorsal rays, as well as its scaleless breast. Longfin trevally are pelagic predators, taking a variety of small fish, cephalopods and crustaceans, and reach sexual maturity at around 21 cm. The species has a maximum known length of 57 cm and weight of 3.5 kg. The longfin trevally has a very complex taxonomic history which is closely intertwined with another currently valid species, Carangoides ciliarius, which may yet prove to be synonymous. Longfin trevally are of minor importance to fisheries throughout their range and are considered good table fish, and are occasionally taken by anglers.
The longnose trevally, also known as the tea-leaf trevally, club-nosed trevally, grunting trevally or dusky trevally, is a species of inshore marine fish in the jack family, Carangidae. The species is distributed throughout the tropical and subtropical waters of the Indian and west Pacific Oceans from South Africa to New Zealand and Japan, inhabiting coastal waters, especially reefs, to a depth of 90 m. The longnose trevally is distinguished from similar species by a combination of a scaleless breast and the number of gill rakers and fin rays. It is a moderately large fish, growing to a maximum known length of 72 cm and 4.35 kg. The longnose trevally is a predatory fish, consuming small fish, crustaceans and molluscs. The species is of minor commercial importance throughout its range, and is considered to be a good table fish.
The coastal trevally, also known as the onion trevally, Japanese trevally or bluefin kingfish, is a species of inshore marine fish in the jack family Carangidae. The species is distributed throughout the tropical and subtropical waters of the Indian and west Pacific Oceans, from South Africa in the west to Japan and New Caledonia in the east, reaching as far south as Australia. The species is found on deep coastal reefs, both in schools and as solitary individuals, where they prey on small midwater organisms including crustaceans, small fish and cephalopods. The species is taken as bycatch in a number of fisheries throughout its range by a number of fishing methods and is of little commercial value, but is considered to be a good table fish. A mistype in the original volume in which Eduard Rüppell named the species led to the combination Carangoides caeruleopinnatus, which has incorrectly spread through the literature.
The shadow trevally, also known as the shadow kingfish, twothread trevally or Aldabra trevally, is a species of inshore marine fish in the jack family Carangidae. The species is patchily distributed throughout the tropical and subtropical waters of the Indian and west Pacific Oceans, from South Africa in the west to Japan and Samoa in the east, reaching as far south as Indonesia and New Caledonia. It is most easily distinguished from similar species by as series of dark rectangular blotches under the second dorsal fin, giving a 'shadowed' appearance, from which its common name is derived. The shadow trevally is a reasonably large fish, growing to 85 cm in length and at least 2.6 kg in weight. It inhabits shallow coastal waters, including reefs, bays, and estuaries, where it takes small fish and benthic crustaceans as prey. Nothing is known of the species' ecology and reproductive biology. It is of little importance to fisheries, and is occasionally taken by bottom trawls and other artisanal fishing gear.
The blue trevally, also known as the banded trevally, barred trevally, Ferdau's trevally or Forskaal's jackfish, is a common, widespread species of pelagic marine fish classified in the jack family, Carangidae. The blue trevally is distributed throughout the tropical and subtropical waters of the Indo-Pacific and central Pacific regions, ranging from South Africa in the west to Hawaii in the east. It is a moderately large fish, growing to a recorded maximum length of 70 cm, with the number of rays in the second dorsal fin and the colouring serving as diagnostic features of the species. The species inhabits waters to depths of 60 m, generally inhabiting reefs, beaches, lagoons, and areas with sandy substrates. It is a predatory fish, taking other fish, prawns, crabs, and molluscs, and very little is known of the species' reproductive biology. The blue trevally is of varying importance to fisheries throughout its range, with some regions having high catches of the fish. It is considered to be a gamefish, and is sought after for its excellent eating qualities.
The coachwhip trevally, also known as the oblong trevally or oblique-banded trevally, is a species of inshore marine fish classified in the jack family Carangidae. The coachwhip trevally is distributed through the Indo-west Pacific region, ranging from South Africa in the west to Fiji and Japan in the east. It is a moderately large fish, growing to a known maximum length of 46 cm and can be distinguished from similar species by an array of detailed morphological features including dentition, fin ray counts and scale patterns. The coachwhip trevally inhabits coastal waters throughout its range, known to prefer estuarine waters in a number of localities. Nothing is known of its diet or reproductive biology, and is of little importance to fisheries, occasionally taken as bycatch in trawl and hook and line fisheries.
The barcheek trevally, also known as the barcheek kingfish, shortridge trevally or oblique-banded trevally, is a species of moderately large marine fish of the jack family Carangidae. The barcheek trevally is distributed throughout the tropical waters of the Indo-west Pacific region, ranging from South Africa in the west to Japan, Australia and a number of small central Pacific islands in the east. The species inhabits inshore and offshore waters, found along the slopes of lagoons and out to deeper reefs on the continental shelf, where it preys on small fish and benthic crustaceans. It is a moderately large fish, growing to a maximum recorded length of 50 cm, and can be distinguished from similar species by its somewhat protruding lower jaw and the dark banding on its operculum. It is of minor importance to fisheries throughout its range, taken by trawling, hook and line methods and various inshore fish netting methods.
The Senegal jack, also known as the African jack, is a species of large marine fish classified in the jack family Carangidae. The species is distributed through the tropical waters of the eastern Atlantic Ocean, ranging along the west African coast from Angola in the south to Mauritania in the north. It can be distinguished from co-occurring relatives by its longer dorsal fin lobe, as well as a host of other anatomical features. The Senegal jack grows to a known maximum length of 1 m. It is a coastal species, known to live semi-pelagically, inhabiting both the sea floor and surface waters to depths of around 200 m. The Senegal jack is a predatory species, taking fish, crabs and shrimps as its main prey items. The species reaches sexual maturity at 21 cm in females and 24 cm in males, with spawning occurring in two periods; February to April and September to November. The species is of minor importance to fisheries, and is not discriminated from other jacks in catch statistics. It is taken by trawls, seines and hook and line, and sold fresh or preserved.
The longrakered trevally, also known as the cale cale trevally and heavyjawed kingfish, is a species of marine fish in the jack and horse mackerel family Carangidae. The longrakered trevally is distributed throughout the tropical and subtropical waters of the Indian and west Pacific Oceans, from Mozambique and Madagascar in the west, to Japan and northern Australia in the east. A large species growing to a recorded length of 1 m, the longrakered trevally is distinguished by is protruding lower jaw, elongated gill rakers and lack of villiform teeth on its tongue. It is an inshore species, restricted to coastal and estuarine regions, where it preys on fishes and crustaceans. Little is known of the species reproductive cycle or growth. The longrakered trevally is of minor importance to fisheries and is often taken as bycatch in finfish and prawn trawls, as well as by recreational fishermen.
The Indian Scad, also known as the Northern mackerel scad, round scad, Russell's mackerel scad, slender scad or the three lined grunter, is a species of ray-finned fish of the genus Decapterus which is part of the family Carangidae and which occurs in the Indian Ocean. It has colonised the eastern Mediterranean through the Suez Canal. It is an important species in coastal fisheries throughout its range.
The Arabian scad is a species of jack mackerel from the family Carangidae which is found in the Western Indian Ocean.
Aphareus rutilans, the rusty jobfish, ironjaw snapper, red smalltooth job, silvermouth or small tooth jobfish, is a species of marine ray-finned fish, a snapper belonging to the family Lutjanidae. It is found in the Indo-Pacific region.
Lepidotrigla spiloptera, the spotwing gurnard, spotfin gurnard or red-fringed gurnard, is a species of marine, demersal ray-finned fish from the family Triglidae, the gurnards and sea robins. It has a wide Indo-Pacific distribution.
