Imposter trevally
Encyclopedia
The imposter trevally, Carangoides talamparoides (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 ocean
s, 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, crustacean
s and cephalopod
s, 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 artisan
al gear.
Carangoides
, one of a number of groups of fish referred to as jacks and trevallies. Carangoides is further classified in the family Carangidae
, itself part of the suborder Percoidei
and the order Perciformes
; the perch-like fishes.
The species was first scientifically described by the Dutch
ichthyologist Pieter Bleeker
in 1852 based on the holotype
specimen taken from western Sumatra
in Indonesia
. Bleeker named this new species Carangoides talamparoides, with the specific epithet having a slightly ambiguous meaning. Talam is a length measurement spanning the length of the thumb to little finger, par is Greek
for 'equal' and oides translates to 'like' - possibly indicating the small size of the holotype. Bleeker's classification is still considered to be correct to this day, with some authors incorrectly reassigning the species to Caranx
, and only one junior synonym has been applied; Carangoides gibber by Henry Weed Fowler
.
ed almost ovate body, with the dorsal profile somewhat more convex than the ventral. This asymmetry is due to the dorsal profile of the head being strongly elevated to the nape
. The dorsal fin
is in two distinct sections; the first consisting of 8 spines and the second of 1 spine and 20 to 23 soft rays. The long section of the anal fin is preceded by two detached spines, while the main fin has 1 spine and 17 to 19 soft rays. The lobes of both the soft dorsal and anal fins are low, being shorter than the head length. The lateral line
has a moderate anterior arch, with the curved section of the line much longer than the straight section. There are 32 to 52 scale
s on the lateral line, with 20 to 32 of these being weak scute
s at the base of the caudal fin. The breast is devoid of scales, with this area extending to behind the pelvic fins, and often as far as the anal fin, and reaching as far up as the pectoral fin base. The jaws both have bands of small villiform teeth, with some outer teeth becoming conical at the front of the mouth. There are 27 to 31 gill raker
s and 24 vertebrae in total.
The imposter trevally is a silver to bluish grey dorsally, becoming silvery white below. A major distinguishing feature is the white to pale grey tongue, with this also seen in the carangid genus Uraspis although their different body shapes prevent confusion with C. talamparoides. The operculum
has a small black spot on its upper margin. The soft dorsal and anal fins are dusky in colour, while the caudal fin is dusky yellow with black distal margins.
and west Pacific Ocean
s. Its range extends from the Gulf of Oman
through to India
and Sri Lanka
in the west, with a break in records from Sri Lanka to the Gulf of Thailand
. In the west Pacific the imposter trevally inhabits South East Asian waters from the Gulf of Thailand to Sumatra
and Borneo
. It is distributed east towards the Philippines
and Guam
, and south to Australia
.
The imposter trevally inhabits coastal waters throughout its range, often found over the sandy continental shelf
in the waters off North West Australia. Here it is known to form cohabit with Carangoides coeruleopinnatus and Carangoides malabaricus in waters 30 to 140 m deep.
of the imposter trevally, which was carried out in Albatross Bay, Australia. It was found teleost fish made up 73% of its diet, cephalopod
s 16% and a variety of crustacean
s including brachyurans and stomatopods the remainder. It is thought that the coexisting C. coeruleopinnatus and C. malabaricus use diet partitioning to allow this cohabitation. Nothing is known of the species reproduction and growth patterns.
The imposter trevally is of little importance to fisheries throughout its range, occasionally caught using hook and line, bottom trawls and various types of artisinal nets. It is often found in the bycatch of northern Australian prawn
trawlers, and usually discarded.
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 small coastal marine fish
Coastal fish
Coastal fish, also called offshore fish or neritic fish, are fish that inhabit the sea between the shoreline and the edge of the continental shelf. Since the continental shelf is usually less than 200 metres deep, it follows that pelagic coastal fish are generally epipelagic fish, inhabiting the...
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 imposter trevally is distributed through the tropical waters of 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 ocean
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...
s, from the Gulf of Oman
Gulf of Oman
The Gulf of Oman or Sea of Oman is a strait that connects the Arabian Sea with the Strait of Hormuz, which then runs to the Persian Gulf. It is generally included as a branch of the Persian Gulf, not as an arm of the Arabian Sea. On the north coast is Pakistan and Iran...
in the west to 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...
and 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...
in the east. The species is quite similar to the Malabar trevally
Malabar trevally
The Malabar trevally, Carangoides malabaricus, is a species of large inshore marine fish of the jack family, Carangidae...
, but can be distinguished by its 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...
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
Continental shelf
The continental shelf is the extended perimeter of each continent and associated coastal plain. Much of the shelf was exposed during glacial periods, but is now submerged under relatively shallow seas and gulfs, and was similarly submerged during other interglacial periods. The continental margin,...
in depths of up to 140 m, often associating with closely related carangid species. It preys on a range of small fish, 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 and cephalopod
Cephalopod
A cephalopod is any member of the molluscan class Cephalopoda . These exclusively marine animals are characterized by bilateral body symmetry, a prominent head, and a set of arms or tentacles modified from the primitive molluscan foot...
s, 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 artisan
Artisan
An artisan is a skilled manual worker who makes items that may be functional or strictly decorative, including furniture, clothing, jewellery, household items, and tools...
al gear.
Taxonomy and naming
The imposter trevally is classified within the genusGenus
In biology, a genus is a low-level taxonomic rank used in the biological classification of living and fossil organisms, which is an example of definition by genus and differentia...
Carangoides
Carangoides
Carangoides is a genus of tropical to subtropical marine fishes in the jack family, Carangidae. They are small to large sized, deep bodied fish characterised by a certain gill raker and jaw morphology, often appearing very similar to jacks in the genus Caranx...
, one of a number of groups of fish referred to as jacks and trevallies. Carangoides is further classified in the 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...
, itself part of the suborder Percoidei
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:...
and 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 perch-like fishes.
The species was first scientifically described by the Dutch
Netherlands
The Netherlands is a constituent country of the Kingdom of the Netherlands, located mainly in North-West Europe and with several islands in the Caribbean. Mainland Netherlands borders the North Sea to the north and west, Belgium to the south, and Germany to the east, and shares maritime borders...
ichthyologist Pieter Bleeker
Pieter Bleeker
Pieter Bleeker was a Dutch medical doctor and ichthyologist, famous for his work on the fishes of East Asia – Atlas Ichthyologique des Orientales Neerlandaises – which was published 1862–1877....
in 1852 based on 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...
specimen taken from western Sumatra
Sumatra
Sumatra is an island in western Indonesia, westernmost of the Sunda Islands. It is the largest island entirely in Indonesia , and the sixth largest island in the world at 473,481 km2 with a population of 50,365,538...
in Indonesia
Indonesia
Indonesia , officially the Republic of Indonesia , is a country in Southeast Asia and Oceania. Indonesia is an archipelago comprising approximately 13,000 islands. It has 33 provinces with over 238 million people, and is the world's fourth most populous country. Indonesia is a republic, with an...
. Bleeker named this new species Carangoides talamparoides, with the specific epithet having a slightly ambiguous meaning. Talam is a length measurement spanning the length of the thumb to little finger, par is Greek
Greek language
Greek is an independent branch of the Indo-European family of languages. Native to the southern Balkans, it has the longest documented history of any Indo-European language, spanning 34 centuries of written records. Its writing system has been the Greek alphabet for the majority of its history;...
for 'equal' and oides translates to 'like' - possibly indicating the small size of the holotype. Bleeker's classification is still considered to be correct to this day, with some authors incorrectly reassigning the species to Caranx
Caranx
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...
, and only one junior synonym has been applied; Carangoides gibber by Henry Weed Fowler
Henry Weed Fowler
Henry Weed Fowler was an American zoologist born in Holmesburg, Pennsylvania.He studied at Stanford University under David Starr Jordan...
.
Description
The imposter trevally is a relatively small species, growing to a maximum known length of 30 cm, still making it small compared to many of its relatives. The overall shape of the fish is similar to most of the other species in Carangoides, having a strongly compressCompress
Compress is a UNIX compression program based on the LZC compression method, which is an LZW implementation using variable size pointers as in LZ78.- Description of program :Files compressed by compress are typically given the extension .Z...
ed almost ovate body, with the dorsal profile somewhat more convex than the ventral. This asymmetry is due to the dorsal profile of the head being strongly elevated to the nape
Nape
The nape is the back of the neck. In technical anatomical/medical terminology, the nape is referred to by the word nucha, which also gives the adjective corresponding to "nape" in English, "nuchal"....
. 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 sections; the first consisting of 8 spines and the second of 1 spine and 20 to 23 soft rays. The long section of the anal fin is preceded by two detached spines, while the main fin has 1 spine and 17 to 19 soft rays. The lobes of both the soft dorsal and anal fins are low, being shorter than the head length. 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...
has a moderate anterior arch, with the curved section of the line much longer than the straight section. There are 32 to 52 scale
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...
s on the lateral line, with 20 to 32 of these being weak 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 at the base of the caudal fin. The breast is devoid of scales, with this area extending to behind the pelvic fins, and often as far as the anal fin, and reaching as far up as the pectoral fin base. The jaws both have bands of small villiform teeth, with some outer teeth becoming conical at the front of the mouth. There are 27 to 31 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 in total.
The imposter trevally is a silver to bluish grey dorsally, becoming silvery white below. A major distinguishing feature is the white to pale grey tongue, with this also seen in the carangid genus Uraspis although their different body shapes prevent confusion with C. talamparoides. The operculum
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....
has a small black spot on its upper margin. The soft dorsal and anal fins are dusky in colour, while the caudal fin is dusky yellow with black distal margins.
Distribution and habitat
The imposter trevally inhabits the tropical 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 Ocean
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...
s. Its range extends from the Gulf of Oman
Gulf of Oman
The Gulf of Oman or Sea of Oman is a strait that connects the Arabian Sea with the Strait of Hormuz, which then runs to the Persian Gulf. It is generally included as a branch of the Persian Gulf, not as an arm of the Arabian Sea. On the north coast is Pakistan and Iran...
through to 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...
and Sri Lanka
Sri Lanka
Sri Lanka, officially the Democratic Socialist Republic of Sri Lanka is a country off the southern coast of the Indian subcontinent. Known until 1972 as Ceylon , Sri Lanka is an island surrounded by the Indian Ocean, the Gulf of Mannar and the Palk Strait, and lies in the vicinity of India and the...
in the west, with a break in records from Sri Lanka to the Gulf of Thailand
Gulf of Thailand
The Gulf of Thailand , also known in to Malays as Teluk Siam literally meant Gulf of Siam, is a shallow arm of the South China Sea.-Geography:...
. In the west Pacific the imposter trevally inhabits South East Asian waters from the Gulf of Thailand to Sumatra
Sumatra
Sumatra is an island in western Indonesia, westernmost of the Sunda Islands. It is the largest island entirely in Indonesia , and the sixth largest island in the world at 473,481 km2 with a population of 50,365,538...
and Borneo
Borneo
Borneo is the third largest island in the world and is located north of Java Island, Indonesia, at the geographic centre of Maritime Southeast Asia....
. It is distributed east towards the Philippines
Philippines
The Philippines , officially known as the Republic of the Philippines , is a country in Southeast Asia in the western Pacific Ocean. To its north across the Luzon Strait lies Taiwan. West across the South China Sea sits Vietnam...
and Guam
Guam
Guam is an organized, unincorporated territory of the United States located in the western Pacific Ocean. It is one of five U.S. territories with an established civilian government. Guam is listed as one of 16 Non-Self-Governing Territories by the Special Committee on Decolonization of the United...
, and south to 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...
.
The imposter trevally inhabits coastal waters throughout its range, often found over the sandy continental shelf
Continental shelf
The continental shelf is the extended perimeter of each continent and associated coastal plain. Much of the shelf was exposed during glacial periods, but is now submerged under relatively shallow seas and gulfs, and was similarly submerged during other interglacial periods. The continental margin,...
in the waters off North West Australia. Here it is known to form cohabit with Carangoides coeruleopinnatus and Carangoides malabaricus in waters 30 to 140 m deep.
Biology and fishery
Only one study has thoroughly recorded the dietDiet (nutrition)
In nutrition, diet is the sum of food consumed by a person or other organism. Dietary habits are the habitual decisions an individual or culture makes when choosing what foods to eat. With the word diet, it is often implied the use of specific intake of nutrition for health or weight-management...
of the imposter trevally, which was carried out in Albatross Bay, Australia. It was found teleost fish made up 73% of its diet, cephalopod
Cephalopod
A cephalopod is any member of the molluscan class Cephalopoda . These exclusively marine animals are characterized by bilateral body symmetry, a prominent head, and a set of arms or tentacles modified from the primitive molluscan foot...
s 16% and a variety of 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 including brachyurans and stomatopods the remainder. It is thought that the coexisting C. coeruleopinnatus and C. malabaricus use diet partitioning to allow this cohabitation. Nothing is known of the species reproduction and growth patterns.
The imposter trevally is of little importance to fisheries throughout its range, occasionally caught using hook and line, bottom trawls and various types of artisinal nets. It is often found in the bycatch of northern Australian 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...
trawlers, and usually discarded.