Herring scad | |
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Scientific classification | |
Kingdom: | Animalia |
Phylum: | Chordata |
Class: | Actinopterygii |
Order: | Carangiformes |
Family: | Carangidae |
Genus: | Alepes |
Species: | A. vari |
Binomial name | |
Alepes vari (G. Cuvier, 1833) | |
Approximate range of the herring scad | |
Synonyms | |
The herring scad (Alepes vari) (also known as the duskyfin crevalle and trevally scad), is a common species of tropical marine fish in the jack family Carangidae. The species inhabits the surface waters of coastal regions throughout the Indo-West Pacific region, feeding on a variety of crustaceans and small fishes. It is the largest fish of the scad genus Alepes , growing to a recorded length of 56 cm. The herring scad is identified among the genus Alepes by its more numerous and smaller scutes and the number of gill rakers on the first arch. It is of minor importance to fisheries throughout its range.
The herring scad is one of five extant species in the scad genus Alepes, a group of fish in the jack family, Carangidae. The Carangidae are part of the order Carangiformes. [2]
The species was first scientifically described by the French naturalist Georges Cuvier in 1833 from a specimen now lost to science. [3] He named the species Caranx vari, believing the fish was closely affiliated with the large jacks of that genus. The species was later transferred to the scad genus Alepes by Gushiken in 1983, and a specimen from Puducherry, India was designated to be the lectotype the following year by Smith-Vaniz. [4] The species was redescribed and renamed twice after Cuvier's description, first by Pieter Bleeker as Selar macrurus and then by Henry Fowler as Alepes glabra, both of which are junior synonyms discarded under ICZN rules. Although commonly called the 'herring scad', the names duskyfin crevalle, trevally scad and, incorrectly, blackfin scad ( A. melanoptera ) are applied to the species. [5]
The herring scad has a body profile very similar to other members of the genus Alepes, having a strongly compressed, ovate body. The ventral and dorsal profiles of the fish are almost evenly convex, joined anteriorally by a pointed snout. There are two separate dorsal fins, the first containing 8 spines while the second has a single spine followed by 24 to 27 soft rays. The anal fin consists of two anteriorally detached small spines followed by a single spine connected to 20 to 23 soft rays. [6] The lateral line is strongly arched anteriorally with the junction of the curved and straight sections located the origin of second dorsal to the third soft ray. The curved section contains 42 to 50 scales and 0 to 2 scutes, while the straight section has 0 to 7 scales and 48 to 69 scutes. [7] There is a well-developed adipose eyelid on the posterior half of the eye. The jaws hold a single row of numerous comb like teeth. There are 32 to 38 gill rakers and a total of 24 vertebrae. The herring scad is by far the largest species in Alepes, growing to 56 cm in total length, although is more commonly encountered at below 30 cm. [8]
The species is an ash blue above, fading to a silvery white below, with a diffuse dusky blotch on margin of operculum. The fins are dusky with the exception of the spinous dorsal fin which is pale to dark dusky. The amount of dark pigment in the fins is sexually dimorphic, with males developing darker spinous dorsal fin, lobes of soft dorsal and anal fins, and pelvic fins than females. [8]
The herring scad is distributed throughout tropical to subtropical regions of the Indo-West Pacific oceans. The species has been recorded from the Red Sea, eastward to Sri Lanka, India, Southeast Asia, China, Indonesia, the Philippines, New Guinea, and as far north as Taiwan [4] and as far south as northern Australia. [9] The herring scad is most commonly found in shallow coastal regions where it inhabits the surface layers of the ocean over a variety of substrates. [8]
The herring scad is a carnivorous species, known to consume a variety of crustaceans including shrimps, copepods and decapods as well as other small fishes. It is one of a number of pelagic fish from the Red Sea found to have high numbers of luminescent bacteria in its gut, living symbiotically with the fish as part of the gut flora. [10]
Parasites of the herring scad include the philometrid nematode Philometra austropacifica, which lives inside the ovary of the females. [11]
The species is of little importance to fisheries, taken occasionally on hook and line gear. [8]
The smallmouth scad, is a species of tropical marine fish in the jack family Carangidae. The species is endemic to northern Australia, inhabiting primarily inshore waters. It is similar to other scads in the genus Alepes, and is distinguished by a well-developed posterior adipose eyelid, as well as fin membrane spotting and gill raker counts. It is not a large species, with the maximum length reported to be 29.5 cm. It feeds primarily on a variety of small invertebrates, and is of very minor economic importance.
The shrimp scad, is a species of widespread tropical marine fish of the jack family, Carangidae. The shrimp scad is widely distributed in the tropical and subtropical western Indian Ocean and areas of the eastern Pacific Ocean, ranging from South Africa in the west to Hawaii in the east, including Japan and Australia to the north and south. The species is commonly found on inshore reefs and sandy substrates. It has the common body profile of a scad, and may be difficult to differentiate from others in the genus Alepes. It is one of the larger scads, growing to 40 cm, but often is encountered at much smaller sizes. The shrimp scad often forms large schools, and is carnivorous, consuming a variety of crustaceans and small fish. It is of moderate importance to fisheries throughout its range.
The blackfin scad is a species of tropical marine fish of the jack family Carangidae. The species inhabits inshore waters throughout the Indo-Pacific region, although is rare in the western Indian Ocean. It is not a large species, with the largest reported capture being 25 cm, and it is distinguished readily from similar species by the prominent black dorsal fin. It is a predator which feeds on planktonic crustaceans, but little else is known of its biology. The blackfin scad is a minor food fish throughout its range, and is highly valued in Cambodia and Thailand.
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 razorbelly scad is a small species of tropical marine fish in the jack family, Carangidae. The species inhabits coastal waters in the Indo-Pacific, from Pakistan in the west to Japan and Australia in the east, often found over reefs. The razorbelly scad has a complex taxonomic history, and even recently has had its position in the genus Alepes challenged, but appears to be stable after a molecular phylogeny study supported its placement in Alepes. It is very similar to other scads in the same genus, but is readily identified by its unique teeth. Razorbelly scad are predatory fish, taking a variety of crustaceans and shrimps, and show a change in feeding intensity over the year. Reproduction and development has been extensively studied in India, where spawning occurs in a single event from January to September. The species is commonly taken in tropical fisheries, where it is marketed fresh or dried.
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.
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 genera by specific gill raker, fin ray and dentition characteristics. The genus is represented in the Pacific, Indian and Atlantic Oceans, inhabiting both inshore and offshore regions, ranging from estuaries and bays to deep reefs and offshore islands. All species are powerful predators, taking a variety of fish, crustaceans and cephalopods, while they in turn are prey to larger pelagic fishes and sharks. A number of fish in the genus have a reputation as powerful gamefish and are highly sought by anglers. They often make up high amounts of the catch in various fisheries, but are generally considered poor to fair table fishes.
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 bumpnose trevally, also known as the bumpnose kingfish or onion kingfish, is a species of relatively small inshore marine fish classified in the jack family Carangidae. The bumpnose trevally is fairly common in the tropical and subtropical waters of the Indo-west Pacific region, ranging from South Africa in the west to Japan and Samoa in the east. It is a small species by carangid standards, reaching a maximum known length of 32 cm, and can be distinguished from the similarly shaped Carangoides armatus by a distinct 'bump' on the snout, which gives the fish its common name. The species inhabits coastal waters, often living along bays and beaches, where it takes shrimp, small crabs, and juvenile fish as prey. The bumpnose trevally is of minor importance to fisheries throughout its range, taken by hook and line, trawls, and seine nets. It is also of minor importance to anglers, taken by baits from beaches and piers, and is considered a modest table fish.
The duskyshoulder trevally or epaulet trevally, is a species of small inshore marine fish in the jack family, Carangidae. It is distributed through the eastern Indian and western Pacific Oceans, ranging from eastern India to northern Australia and Taiwan. It is relatively small by carangid standards, reaching only 27 cm maximum length, and can be distinguished by the large, black blotches on its shoulders. The duskyshoulder trevally is an inshore fish living in waters less than 50 m deep, over sandy substrates in bays and on the continental shelf. It is a predatory fish, taking demersal fishes, crustaceans, and cephalopods, with nothing known of its reproductive habits. It is of little value to fisheries, often taken as bycatch in prawn trawling operations.
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 brownback trevally, also known as the brown-backed trevally, is a species of small inshore marine fish classified in the jack family, Carangidae. The brownback trevally is distributed in two populations through the tropical waters of the Indo-west Pacific region, ranging from the Persian Gulf east to India, South East Asia and the Indonesian islands. The species is distinguished from similar species by its completely scaled breast and black-tipped second dorsal fin, and is known to reach a maximum length of 25 cm. The brownback trevally inhabits inshore waters including bays and estuaries, where it preys on demersal crustaceans and small fish. Other aspects of its biology are poorly known, and it is of minor importance to fisheries, occasionally caught by hook and line or trawls. William Smith-Vaniz has recently suggested the two distinct populations may actually represent two distinct species.
The imposter trevally, also known as the imposter jack or white-tongued trevally, is a species of small coastal marine fish in the jack family Carangidae. The imposter trevally is distributed through the tropical waters of Indian and west Pacific oceans, from the Gulf of Oman in the west to Japan and Australia in the east. The species is quite similar to the Malabar trevally, but can be distinguished by its gill raker count, and is identifiable from other species by having a white to pale grey tongue. It is a relatively small species, growing to a maximum recorded length of 30 cm. The imposter trevally inhabits coastal waters of the continental shelf in depths of up to 140 m, often associating with closely related carangid species. It preys on a range of small fish, crustaceans and cephalopods, but little is known of its reproductive biology. The imposter trevally is of minor importance to fisheries throughout its range, taken by hook and line, bottom trawls and several types of artisanal gear.
The fringefin trevally, also called fringe-finned trevally, round-finned trevally or reef herring, is a species of inshore marine fish classified in the jack and horse mackerel family Carangidae. A relatively small fish, the fringefin trevally is known to reach 40 cm (16 in), but is mostly encountered at lengths less than 25 cm (9.8 in). The fringefin trevally has an ovate body, with distinctive orange-yellow fins and a black opercular spot. The dental patterns of the species distinguish it from the closely related scads of the genus Alepes. Males have characteristic elongated dorsal and anal fins which produce a series of trailing filaments. The fringefin trevally is restricted to the waters of the Indo-Pacific, ranging from northern Australia to Papua New Guinea and eastern Indonesia. An inshore species, it is found in coastal and estuarine environments and exhibits daily and seasonal movements. The fringefin trevally is predatory, taking crustaceans as prey. The species is often taken as bycatch in prawn trawls and occasionally taken by anglers.
The yellowstripe scad, also known as the yellowstripe trevally, yellow-banded trevally, smooth-tailed trevally, slender-scaled trevally and slender trevally, is a species of small inshore fish in the jack and horse mackerel family Carangidae, and the only member of the genus Selaroides. The yellowstripe trevally is distributed throughout the tropical waters of the Indo-West Pacific region, ranging from the Persian Gulf in the west to Vanuatu and New Caledonia in the east. The species is distinguished by its prominent lateral yellow band, and differs from the scads of the genus Selar in having a smaller eye and different dentition. The yellowstripe scad reaches a maximum recorded length of 22 cm, however is normally encountered at sizes less than 15 cm. Phylogenetic studies indicate the yellowstripe scad is closely related to the scads of the genus Selar, although its exact placement in the family Carangidae is less well agreed upon.
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.