Brassy trevally
Encyclopedia
The brassy trevally, Caranx papuensis (also known as the brassy kingfish, Papuan trevally, tea-leaf trevally and green back trevally) is a species
of large marine
fish
classified in the jack family, Carangidae
. The brassy trevally is distributed throughout the tropical waters of the Indian
and West Pacific Oceans
, ranging from South Africa
in the west to the Marquesas Islands
in the east, including Australia
to the south and Japan
in the north. The brassy trevally is best distinguished by its colouration, having small black spots scattered above and below its lateral line
, with a narrow white outside edge to its lower caudal fin. The species grows to a known maximum length of 88 cm and a weight of at least 6.4 kg
. It predominatly inhabits both coastal and offshore
reef
s, as well as inshore lagoon
s, bays and even estuarine waters as a juvenile. It is a predatory species, moving either individually or small schools, where it takes small fish and occasionally squid
and crustacean
s. Nothing is known of its reproductive cycle. The brassy trevally is not of great importance to commercial fisheries, but is taken in many netting and hook and line operations throughout its range. It is valued as a gamefish by anglers and spearfishermen
, and is considered an excellent table fish.
, one of a number of groups known as the jacks or trevallies. Caranx itself is part of the larger jack and horse mackerel family Carangidae
, a group of percoid
fishes in the order Perciformes
.
The species was first scientifically described by the Australian zoologists Haynes Gibbs Alleyne and William John Macleay
in 1877 based on a specimen collected from Hall Sound off Papua New Guinea
which was designated to be the holotype
. They named the species Caranx papuensis, with the specific epithet taking its name from Papua New Guinea where the holotype was taken. They referred the species to the genus Caranx, where it has remained. The species was independently redescribed twice; the first by Samuel Garman, who applied the name Caranx regularis and then by J.L.B. Smith
with the name Caranx celetus. The species was apparently widely confused with the now dubious Caranx sansun, a move which resulted in Smith trying to resolve the taxon
by renaming the species that had been identified as C. sansun, which led to several now defunct junior synonyms.
The species is commonly referred
to as the 'brassy trevally', 'tea-leaf trevally' or 'green back trevally' in reference to its colouration, while 'Papuan trevally' is used in reference to the specific epithet.
in weight. It is often confused with the giant trevally
, Caranx ignobilis, but is best distinguished by its lighter dorsal colouring and abundant black spots. It is similar in general appearance to most jacks in the genus, having a compressed, oblong
body, with the dorsal profile more convex than the ventral profile, particularly anteriorly. The dorsal fin
is in two distinct parts; the first consisting of 8 spine and the second of 1 spine and 21 to 23 soft rays. The anal fin consists of 2 anteriorly detached spines followed by 1 spine and 16 to 19 soft rays, while the pelvic fins have 1 spine followed by 19 to 20 soft rays. The lateral line
is moderately arched anteriorly, with 53 to 61 scales in this section, while the straight section contains 0 to 3 scales
and 31 to 39 strong scute
s. The breast is naked ventrally with the exception of a small patch of scales before the pelvic fin. The species has weakly developed adipose eyelids, while its dentition consists of an outer row of widely-spaced canine
s and an inner band of villiform teeth in the upper jaw
with a row of widely-spaced conical teeth on the lower jaw. The brassy trevally has 26 to 30 gill raker
s and 24 vertebrae.
As its name suggests, the brassy trevally is a brassy to yellow greenish colour dorsally, becoming silvery white on the underside. Juveniles generally lack the brassy tinge, being silver all over. The species head and body above the lateral line is scattered with small black spots, with few spots occasionally much lower near the pectoral fins. These spots become more numerous with age. The species also has a conspicuous pale silvery-white spot with black margins shoulder near the upper opercle
. The fins are yellow to dusky with the exception of the caudal fin which has a dusky upper lobe and a dusky to yellow lower lobe and distinctive narrow white band on the trailing edge.
and West Pacific Oceans
. Its range extends from South Africa
and Madagascar
north along the east Africa
n coast, but no records of the species are known from the Red Sea
or Persian Gulf
. Records resume from India
eastward throughout South East Asia, the Indonesian Archipelago
and numerous Indian Ocean and east Pacific island groups. The species is known from as far south as Sydney, Australia and as far north as the Ryukyu Islands
of Japan
. Its range extends eastward to the Marquesas Islands
in the central Pacific.
The brassy trevally inhabits both inshore and offshore
environments, predominantly inhabiting the seaward side of reef
complexes or deep water pinnacles as an adult. Other habitats the species is known from include rock outcrops in sandy bays and lagoon
s, while juveniles are often found in tidal mangrove
lined creeks in turbid waters. Juveniles are also found in estuaries throughout their range, occasionally extending to the upper reaches of rivers.
, prawn
s and crab
s. Studies on the species in Natal
estuaries found juveniles take predominantly crustacean
s as prey, switching to teleosts as they mature. Other aspects of the species biology are poorly understood, including reproduction and movements, although catch data indicates higher numbers occur in South Africa in summer.
The brassy trevally is not of high importance to commercial fisheries, often finding its way to market as bycatch
in various netting and hook and line fisheries. Catch statistics are not kept for the species. The species is of some importance to recreational fishermen
, and is considered a good gamefish and is often taken by various fish baits as well as lures
and flies. Despite this, it is rarely targeted by anglers, who overlook it for larger relatives such as giant trevally and bluefin trevally
, with the species often being an incidental catch, and rarely kept. The species is also commonly taken by spearfishermen
. Brassy trevally is considered to be an excellent table fish. The species has been held in large saltwater aquaria, with studies at the Reunion Island Aquarium reporting the species adjusts to aquarium life, but needs a large tank.
Species
In biology, a species is one of the basic units of biological classification and a taxonomic rank. A species is often defined as a group of organisms capable of interbreeding and producing fertile offspring. While in many cases this definition is adequate, more precise or differing measures are...
of large marine
Marine (ocean)
Marine is an umbrella term. As an adjective it is usually applicable to things relating to the sea or ocean, such as marine biology, marine ecology and marine geology...
fish
Fish
Fish are a paraphyletic group of organisms that consist of all gill-bearing aquatic vertebrate animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish, as well as various extinct related groups...
classified in the jack family, Carangidae
Carangidae
Carangidae is a family of fish which includes the jacks, pompanos, jack mackerels, and scads.They are marine fish found in the Atlantic, Indian and Pacific Oceans...
. The brassy trevally is distributed throughout the tropical waters of the Indian
Indian Ocean
The Indian Ocean is the third largest of the world's oceanic divisions, covering approximately 20% of the water on the Earth's surface. It is bounded on the north by the Indian Subcontinent and Arabian Peninsula ; on the west by eastern Africa; on the east by Indochina, the Sunda Islands, and...
and West Pacific Oceans
Pacific Ocean
The Pacific Ocean is the largest of the Earth's oceanic divisions. It extends from the Arctic in the north to the Southern Ocean in the south, bounded by Asia and Australia in the west, and the Americas in the east.At 165.2 million square kilometres in area, this largest division of the World...
, ranging from South Africa
South Africa
The Republic of South Africa is a country in southern Africa. Located at the southern tip of Africa, it is divided into nine provinces, with of coastline on the Atlantic and Indian oceans...
in the west to the Marquesas Islands
Marquesas Islands
The Marquesas Islands enana and Te Fenua `Enata , both meaning "The Land of Men") are a group of volcanic islands in French Polynesia, an overseas collectivity of France in the southern Pacific Ocean. The Marquesas are located at 9° 00S, 139° 30W...
in the east, including Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...
to the south and Japan
Japan
Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...
in the north. The brassy trevally is best distinguished by its colouration, having small black spots scattered above and below its lateral line
Lateral line
The lateral line is a sense organ in aquatic organisms , used to detect movement and vibration in the surrounding water. Lateral lines are usually visible as faint lines running lengthwise down each side, from the vicinity of the gill covers to the base of the tail...
, with a narrow white outside edge to its lower caudal fin. The species grows to a known maximum length of 88 cm and a weight of at least 6.4 kg
Kilogram
The kilogram or kilogramme , also known as the kilo, is the base unit of mass in the International System of Units and is defined as being equal to the mass of the International Prototype Kilogram , which is almost exactly equal to the mass of one liter of water...
. It predominatly inhabits both coastal and offshore
Shore
A shore or shoreline is the fringe of land at the edge of a large body of water, such as an ocean, sea, or lake. In Physical Oceanography a shore is the wider fringe that is geologically modified by the action of the body of water past and present, while the beach is at the edge of the shore,...
reef
Reef
In nautical terminology, a reef is a rock, sandbar, or other feature lying beneath the surface of the water ....
s, as well as inshore lagoon
Lagoon
A lagoon is a body of shallow sea water or brackish water separated from the sea by some form of barrier. The EU's habitat directive defines lagoons as "expanses of shallow coastal salt water, of varying salinity or water volume, wholly or partially separated from the sea by sand banks or shingle,...
s, bays and even estuarine waters as a juvenile. It is a predatory species, moving either individually or small schools, where it takes small fish and occasionally squid
Squid
Squid are cephalopods of the order Teuthida, which comprises around 300 species. Like all other cephalopods, squid have a distinct head, bilateral symmetry, a mantle, and arms. Squid, like cuttlefish, have eight arms arranged in pairs and two, usually longer, tentacles...
and crustacean
Crustacean
Crustaceans form a very large group of arthropods, usually treated as a subphylum, which includes such familiar animals as crabs, lobsters, crayfish, shrimp, krill and barnacles. The 50,000 described species range in size from Stygotantulus stocki at , to the Japanese spider crab with a leg span...
s. Nothing is known of its reproductive cycle. The brassy trevally is not of great importance to commercial fisheries, but is taken in many netting and hook and line operations throughout its range. It is valued as a gamefish by anglers and spearfishermen
Spearfishing
Spearfishing is an ancient method of fishing that has been used throughout the world for millennia. Early civilizations were familiar with the custom of spearing fish from rivers and streams using sharpened sticks....
, and is considered an excellent table fish.
Taxonomy and naming
The brassy trevally is classified within the genus CaranxCaranx
Caranx is a genus of tropical to subtropical marine fish 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...
, one of a number of groups known as the jacks or trevallies. Caranx itself is part of the larger jack and horse mackerel family Carangidae
Carangidae
Carangidae is a family of fish which includes the jacks, pompanos, jack mackerels, and scads.They are marine fish found in the Atlantic, Indian and Pacific Oceans...
, a group of percoid
Percoidei
Percoidei is one of eighteen suborders of bony fish in the order Perciformes. Many commercially harvested fish species are contained in this suborder, including the snappers, jacks, whitings, groupers, bass, perches and porgies.-Divisions:...
fishes in the order Perciformes
Perciformes
The Perciformes, also called the Percomorphi or Acanthopteri, is one of the largest orders of vertebrates, containing about 40% of all bony fish. Perciformes means perch-like. They belong to the class of ray-finned fish and comprise over 7,000 species found in almost all aquatic environments...
.
The species was first scientifically described by the Australian zoologists Haynes Gibbs Alleyne and William John Macleay
William John Macleay
Sir William John Macleay . was an Australian politician, zoologist and naturalist.-Early life:Macleay was born at Wick, Caithness, Scotland, second son of Kenneth Macleay of Keiss and his wife Barbara, née Horne...
in 1877 based on a specimen collected from Hall Sound off Papua New Guinea
Papua New Guinea
Papua New Guinea , officially the Independent State of Papua New Guinea, is a country in Oceania, occupying the eastern half of the island of New Guinea and numerous offshore islands...
which was designated to be the holotype
Holotype
A holotype is a single physical example of an organism, known to have been used when the species was formally described. It is either the single such physical example or one of several such, but explicitly designated as the holotype...
. They named the species Caranx papuensis, with the specific epithet taking its name from Papua New Guinea where the holotype was taken. They referred the species to the genus Caranx, where it has remained. The species was independently redescribed twice; the first by Samuel Garman, who applied the name Caranx regularis and then by J.L.B. Smith
James Leonard Brierley Smith
James Leonard Brierley Smith, known as J.L.B. Smith was a South African ichthyologist, organic chemist and university professor. He was the first to identify a taxidermied fish as a coelacanth, at the time thought long extinct.-Early life:Born in Graaff Reinet, Smith was the elder of two sons of...
with the name Caranx celetus. The species was apparently widely confused with the now dubious Caranx sansun, a move which resulted in Smith trying to resolve the taxon
Taxon
|thumb|270px|[[African elephants]] form a widely-accepted taxon, the [[genus]] LoxodontaA taxon is a group of organisms, which a taxonomist adjudges to be a unit. Usually a taxon is given a name and a rank, although neither is a requirement...
by renaming the species that had been identified as C. sansun, which led to several now defunct junior synonyms.
The species is commonly referred
Common name
A common name of a taxon or organism is a name in general use within a community; it is often contrasted with the scientific name for the same organism...
to as the 'brassy trevally', 'tea-leaf trevally' or 'green back trevally' in reference to its colouration, while 'Papuan trevally' is used in reference to the specific epithet.
Description
The brassy trevally is a large species of fish, growing to a known maximum of 88 cm in length and 6.4 kgKilogram
The kilogram or kilogramme , also known as the kilo, is the base unit of mass in the International System of Units and is defined as being equal to the mass of the International Prototype Kilogram , which is almost exactly equal to the mass of one liter of water...
in weight. It is often confused with the giant trevally
Giant trevally
The giant trevally, Caranx ignobilis , is a species of large marine fish classified in the jack family, Carangidae...
, Caranx ignobilis, but is best distinguished by its lighter dorsal colouring and abundant black spots. It is similar in general appearance to most jacks in the genus, having a compressed, oblong
Rectangle
In Euclidean plane geometry, a rectangle is any quadrilateral with four right angles. The term "oblong" is occasionally used to refer to a non-square rectangle...
body, with the dorsal profile more convex than the ventral profile, particularly anteriorly. The dorsal fin
Dorsal fin
A dorsal fin is a fin located on the backs of various unrelated marine and freshwater vertebrates, including most fishes, marine mammals , and the ichthyosaurs...
is in two distinct parts; the first consisting of 8 spine and the second of 1 spine and 21 to 23 soft rays. The anal fin consists of 2 anteriorly detached spines followed by 1 spine and 16 to 19 soft rays, while the pelvic fins have 1 spine followed by 19 to 20 soft rays. The lateral line
Lateral line
The lateral line is a sense organ in aquatic organisms , used to detect movement and vibration in the surrounding water. Lateral lines are usually visible as faint lines running lengthwise down each side, from the vicinity of the gill covers to the base of the tail...
is moderately arched anteriorly, with 53 to 61 scales in this section, while the straight section contains 0 to 3 scales
Scale (zoology)
In most biological nomenclature, a scale is a small rigid plate that grows out of an animal's skin to provide protection. In lepidopteran species, scales are plates on the surface of the insect wing, and provide coloration...
and 31 to 39 strong scute
Scute
A scute or scutum is a bony external plate or scale, as on the shell of a turtle, the skin of crocodilians, the feet of some birds or the anterior portion of the mesonotum in insects.-Properties:...
s. The breast is naked ventrally with the exception of a small patch of scales before the pelvic fin. The species has weakly developed adipose eyelids, while its dentition consists of an outer row of widely-spaced canine
Canine tooth
In mammalian oral anatomy, the canine teeth, also called cuspids, dogteeth, fangs, or eye teeth, are relatively long, pointed teeth...
s and an inner band of villiform teeth in the upper jaw
Jaw
The jaw is any opposable articulated structure at the entrance of the mouth, typically used for grasping and manipulating food. The term jaws is also broadly applied to the whole of the structures constituting the vault of the mouth and serving to open and close it and is part of the body plan of...
with a row of widely-spaced conical teeth on the lower jaw. The brassy trevally has 26 to 30 gill raker
Gill raker
Gill rakers in fish are bony or cartilaginous processes that project from the branchial arch and are involved with filter feeding tiny prey. They are not to be confused with the gill filaments that compose the bony part of the gill. Rakers are usually present in two rows, projecting from both the...
s and 24 vertebrae.
As its name suggests, the brassy trevally is a brassy to yellow greenish colour dorsally, becoming silvery white on the underside. Juveniles generally lack the brassy tinge, being silver all over. The species head and body above the lateral line is scattered with small black spots, with few spots occasionally much lower near the pectoral fins. These spots become more numerous with age. The species also has a conspicuous pale silvery-white spot with black margins shoulder near the upper opercle
Operculum (fish)
The operculum of a bony fish is the hard bony flap covering and protecting the gills. In most fish, the rear edge of the operculum roughly marks the division between the head and the body....
. The fins are yellow to dusky with the exception of the caudal fin which has a dusky upper lobe and a dusky to yellow lower lobe and distinctive narrow white band on the trailing edge.
Distribution and habitat
The brassy trevally is widespread throughout the tropical and subtropical waters of the IndianIndian Ocean
The Indian Ocean is the third largest of the world's oceanic divisions, covering approximately 20% of the water on the Earth's surface. It is bounded on the north by the Indian Subcontinent and Arabian Peninsula ; on the west by eastern Africa; on the east by Indochina, the Sunda Islands, and...
and West Pacific Oceans
Pacific Ocean
The Pacific Ocean is the largest of the Earth's oceanic divisions. It extends from the Arctic in the north to the Southern Ocean in the south, bounded by Asia and Australia in the west, and the Americas in the east.At 165.2 million square kilometres in area, this largest division of the World...
. Its range extends from South Africa
South Africa
The Republic of South Africa is a country in southern Africa. Located at the southern tip of Africa, it is divided into nine provinces, with of coastline on the Atlantic and Indian oceans...
and Madagascar
Madagascar
The Republic of Madagascar is an island country located in the Indian Ocean off the southeastern coast of Africa...
north along the east Africa
East Africa
East Africa or Eastern Africa is the easterly region of the African continent, variably defined by geography or geopolitics. In the UN scheme of geographic regions, 19 territories constitute Eastern Africa:...
n coast, but no records of the species are known from the Red Sea
Red Sea
The Red Sea is a seawater inlet of the Indian Ocean, lying between Africa and Asia. The connection to the ocean is in the south through the Bab el Mandeb strait and the Gulf of Aden. In the north, there is the Sinai Peninsula, the Gulf of Aqaba, and the Gulf of Suez...
or Persian Gulf
Persian Gulf
The Persian Gulf, in Southwest Asia, is an extension of the Indian Ocean located between Iran and the Arabian Peninsula.The Persian Gulf was the focus of the 1980–1988 Iran-Iraq War, in which each side attacked the other's oil tankers...
. Records resume from India
India
India , officially the Republic of India , is a country in South Asia. It is the seventh-largest country by geographical area, the second-most populous country with over 1.2 billion people, and the most populous democracy in the world...
eastward throughout South East Asia, the Indonesian Archipelago
Malay Archipelago
The Malay Archipelago refers to the archipelago between mainland Southeastern Asia and Australia. The name was derived from the anachronistic concept of a Malay race....
and numerous Indian Ocean and east Pacific island groups. The species is known from as far south as Sydney, Australia and as far north as the Ryukyu Islands
Ryukyu Islands
The , also known as the , is a chain of islands in the western Pacific, on the eastern limit of the East China Sea and to the southwest of the island of Kyushu in Japan. From about 1829 until the mid 20th century, they were alternately called Luchu, Loochoo, or Lewchew, akin to the Mandarin...
of Japan
Japan
Japan is an island nation in East Asia. Located in the Pacific Ocean, it lies to the east of the Sea of Japan, China, North Korea, South Korea and Russia, stretching from the Sea of Okhotsk in the north to the East China Sea and Taiwan in the south...
. Its range extends eastward to the Marquesas Islands
Marquesas Islands
The Marquesas Islands enana and Te Fenua `Enata , both meaning "The Land of Men") are a group of volcanic islands in French Polynesia, an overseas collectivity of France in the southern Pacific Ocean. The Marquesas are located at 9° 00S, 139° 30W...
in the central Pacific.
The brassy trevally inhabits both inshore and offshore
Shore
A shore or shoreline is the fringe of land at the edge of a large body of water, such as an ocean, sea, or lake. In Physical Oceanography a shore is the wider fringe that is geologically modified by the action of the body of water past and present, while the beach is at the edge of the shore,...
environments, predominantly inhabiting the seaward side of reef
Reef
In nautical terminology, a reef is a rock, sandbar, or other feature lying beneath the surface of the water ....
complexes or deep water pinnacles as an adult. Other habitats the species is known from include rock outcrops in sandy bays and lagoon
Lagoon
A lagoon is a body of shallow sea water or brackish water separated from the sea by some form of barrier. The EU's habitat directive defines lagoons as "expanses of shallow coastal salt water, of varying salinity or water volume, wholly or partially separated from the sea by sand banks or shingle,...
s, while juveniles are often found in tidal mangrove
Mangrove
Mangroves are various kinds of trees up to medium height and shrubs that grow in saline coastal sediment habitats in the tropics and subtropics – mainly between latitudes N and S...
lined creeks in turbid waters. Juveniles are also found in estuaries throughout their range, occasionally extending to the upper reaches of rivers.
Biology and fishery
The brassy trevally is a predatory fish, traveling either individually or in small schools, where it hunts down a variety of prey including small fish, squidSquid
Squid are cephalopods of the order Teuthida, which comprises around 300 species. Like all other cephalopods, squid have a distinct head, bilateral symmetry, a mantle, and arms. Squid, like cuttlefish, have eight arms arranged in pairs and two, usually longer, tentacles...
, prawn
Prawn
Prawns are decapod crustaceans of the sub-order Dendrobranchiata. There are 540 extant species, in seven families, and a fossil record extending back to the Devonian...
s and crab
Crab
True crabs are decapod crustaceans of the infraorder Brachyura, which typically have a very short projecting "tail" , or where the reduced abdomen is entirely hidden under the thorax...
s. Studies on the species in Natal
KwaZulu-Natal
KwaZulu-Natal is a province of South Africa. Prior to 1994, the territory now known as KwaZulu-Natal was made up of the province of Natal and the homeland of KwaZulu....
estuaries found juveniles take predominantly crustacean
Crustacean
Crustaceans form a very large group of arthropods, usually treated as a subphylum, which includes such familiar animals as crabs, lobsters, crayfish, shrimp, krill and barnacles. The 50,000 described species range in size from Stygotantulus stocki at , to the Japanese spider crab with a leg span...
s as prey, switching to teleosts as they mature. Other aspects of the species biology are poorly understood, including reproduction and movements, although catch data indicates higher numbers occur in South Africa in summer.
The brassy trevally is not of high importance to commercial fisheries, often finding its way to market as bycatch
Bycatch
The term “bycatch” is usually used for fish caught unintentionally in a fishery while intending to catch other fish. It may however also indicate untargeted catch in other forms of animal harvesting or collecting...
in various netting and hook and line fisheries. Catch statistics are not kept for the species. The species is of some importance to recreational fishermen
Angling
Angling is a method of fishing by means of an "angle" . The hook is usually attached to a fishing line and the line is often attached to a fishing rod. Fishing rods are usually fitted with a fishing reel that functions as a mechanism for storing, retrieving and paying out the line. The hook itself...
, and is considered a good gamefish and is often taken by various fish baits as well as lures
Fishing lure
A fishing lure is an object attached to the end of a fishing line which is designed to resemble and move like the prey of a fish. The purpose of the lure is to use movement, vibration, and colour to catch the fish's attention so it bites the hook...
and flies. Despite this, it is rarely targeted by anglers, who overlook it for larger relatives such as giant trevally and bluefin trevally
Bluefin trevally
The bluefin trevally, Caranx melampygus , is a species of large, widely distributed marine fish classified in the jack family, Carangidae...
, with the species often being an incidental catch, and rarely kept. The species is also commonly taken by spearfishermen
Spearfishing
Spearfishing is an ancient method of fishing that has been used throughout the world for millennia. Early civilizations were familiar with the custom of spearing fish from rivers and streams using sharpened sticks....
. Brassy trevally is considered to be an excellent table fish. The species has been held in large saltwater aquaria, with studies at the Reunion Island Aquarium reporting the species adjusts to aquarium life, but needs a large tank.