The blackfin scad (''Alepes melanoptera'') (also known as the shortfinned trevally and Chinese trevally) is a species of

tropical The tropics are the regions of Earth surrounding the Equator. They are defined in latitude by the Tropic of Cancer in the Northern Hemisphere at N and the Tropic of Capricorn in the Southern Hemisphere at S. The tropics are also referred to ...

marine Marine is an adjective meaning of or pertaining to the sea or ocean. Marine or marines may refer to: Ocean * Maritime (disambiguation) * Marine art * Marine biology * Marine debris * Marine habitats * Marine life * Marine pollution Military * ...

fish Fish are aquatic, craniate, gill-bearing 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. Approximately 95% of li ...

of the jack family Carangidae. The species inhabits inshore waters throughout the

Indo-Pacific The Indo-Pacific is a vast biogeographic region of Earth. In a narrow sense, sometimes known as the Indo-West Pacific or Indo-Pacific Asia, it comprises the tropical waters of the Indian Ocean, the western and central Pacific Ocean, and the ...

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 A dorsal fin is a fin located on the back of most marine and freshwater vertebrates within various taxa of the animal kingdom. Many species of animals possessing dorsal fins are not particularly closely related to each other, though through conv ...

. It is a predator which feeds on

plankton Plankton are the diverse collection of organisms found in Hydrosphere, water (or atmosphere, air) that are unable to propel themselves against a Ocean current, current (or wind). The individual organisms constituting plankton are called plankt ...

crustacean Crustaceans (Crustacea, ) form a large, diverse arthropod taxon which includes such animals as decapods, seed shrimp, branchiopods, fish lice, krill, remipedes, isopods, barnacles, copepods, amphipods and mantis shrimp. The crustacean group ...

s, but little else is known of its biology. The blackfin scad is a minor

food fish Food is any substance consumed by an organism for nutritional support. Food is usually of plant, animal, or fungal origin, and contains essential nutrients, such as carbohydrates, fats, proteins, vitamins, or minerals. The substance is ingest ...

throughout its range, and is highly valued in

Cambodia Cambodia (; also Kampuchea ; km, កម្ពុជា, UNGEGN: ), officially the Kingdom of Cambodia, is a country located in the southern portion of the Indochinese Peninsula in Southeast Asia, spanning an area of , bordered by Thailand t ...

and

Thailand Thailand ( ), historically known as Siam () and officially the Kingdom of Thailand, is a country in Southeast Asia, located at the centre of the Indochinese Peninsula, spanning , with a population of almost 70 million. The country is bo ...

Taxonomy and naming

The blackfin scad is one of five species in the scad genus ''Alepes'', which is one of 33 genera of the jack family, Carangidae. The Carangidae are part of the

order Order, ORDER or Orders may refer to: * Categorization, the process in which ideas and objects are recognized, differentiated, and understood * Heterarchy, a system of organization wherein the elements have the potential to be ranked a number of d ...

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

. The species was first scientifically described by the English naturalist

William John Swainson William John Swainson FLS, FRS (8 October 1789 – 6 December 1855), was an English ornithologist, malacologist, conchologist, entomologist and artist. Life Swainson was born in Dover Place, St Mary Newington, London, the eldest son of ...

under the name of ''Trachinus melanoptera'', placing the species in a new genus which was found to be already in use by an unrelated species of fish. The species was therefore subsequently placed in the new combination of ''Alepes melanoptera'', becoming the

type species In zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the species that contains the biological type specimen ...

of the new genus ''Alepes''. After Swainson's initial description,

Pieter Bleeker Pieter Bleeker (10 July 1819 – 24 January 1878) was a Dutch medical doctor, ichthyologist, and herpetologist. He was famous for the ''Atlas Ichthyologique des Indes Orientales Néêrlandaises'', his monumental work on the fishes of East Asia ...

unknowingly redescribed the species as ''Selar malam'', a name which was revised three times before it too was assigned to ''Alepes''. The species was redescribed twice more by Day in 1876 and Chu and Chen in 1958. Being Swainson is the first author to correctly describe the fish, even though he initially ascribed it to the wrong genus, the

ICZN The International Code of Zoological Nomenclature (ICZN) is a widely accepted convention in zoology that rules the formal scientific naming of organisms treated as animals. It is also informally known as the ICZN Code, for its publisher, the I ...

recognises ''Alepes melanoptera'' as the correct name, and the rest as invalid

junior synonym The Botanical and Zoological Codes of nomenclature treat the concept of synonymy differently. * In botanical nomenclature, a synonym is a scientific name that applies to a taxon that (now) goes by a different scientific name. For example, Linna ...

s. Such synonymy is common in the genus ''Alepes'' due to the abundance of similar genera. The specific name 'melanoptera' literally means 'black wing' in Greek; a reference to its distinctive colouration.

Description

The blackfin scad has a body profile very similar to that of the other round scads of the genus ''Alepes'', in particular to ''

Alepes apercna The smallmouth scad (''Alepes apercna'') (also known as the banded scad and roundfin trevally), is a species of tropical marine fish in the jack family Carangidae. The species is endemic to northern Australia, inhabiting primarily inshore water ...

'', but can be distinguished quite easily by the prominent black colouration of the

. The species has a tendency, like other carangids, to become more elongated with age, thus changing their body proportions slightly. It has an oblong, compressed body with dorsal and ventral profiles that are nearly equally convex in shape. The nose somewhat blunter than others in the genus, and has a mouth full of numerous comb like teeth. Like other members of ''Alepes'', it has an

adipose eyelid An adipose eyelid is a transparent eyelid found in some species of fish, that covers some or all of the eye. They are most commonly found on deep sea (benthic) fish, but can also be seen on non-benthic fish. Fish with this feature include milkfish ...

which is well developed only on the posterior section of the eye. The dorsal fin is split into two sections like in all of the Carangidae, the first with 7 or 8 spines and the second with one spine followed by 23 to 26

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

. The

anal fin Fins are distinctive anatomical features composed of bony spines or rays protruding from the body of a fish. They are covered with skin and joined together either in a webbed fashion, as seen in most bony fish, or similar to a flipper, as se ...

consists of two detached spines followed by a single spine and 18 to 21 soft rays, with both the anal and dorsal fins have a low profile. The

pectoral fin Fins are distinctive anatomical features composed of bony spines or rays protruding from the body of a fish. They are covered with skin and joined together either in a webbed fashion, as seen in most bony fish, or similar to a flipper, as ...

is falcate and extends to beyond the junction of the curved and straight sections of the

lateral line The lateral line, also called the lateral line organ (LLO), is a system of sensory organs found in fish, used to detect movement, vibration, and pressure gradients in the surrounding water. The sensory ability is achieved via modified epithelial ...

. The lateral line itself is strongly arched anteriorally, with the curved and straight sections of the line intersecting just after the commencement of the spinous dorsal fin. The curved section of the lateral line holds 31 to 50

scales Scale or scales may refer to: Mathematics * Scale (descriptive set theory), an object defined on a set of points * Scale (ratio), the ratio of a linear dimension of a model to the corresponding dimension of the original * Scale factor, a number w ...

and up to 2 scutes, while the straight section holds up to 4 scales and 49 to 69 scutes. The

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

s number 24 to 30 and the species has 24

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

. The blackfin scad has a maximum known length of 25 cm. The upper body of the fish is silvery blue above grading to a silvery white below with a diffuse black spot. The membranes of the first, spinous dorsal fin are black, giving the species its common name. All other fins are pale to

hyaline A hyaline substance is one with a glassy appearance. The word is derived from el, ὑάλινος, translit=hyálinos, lit=transparent, and el, ὕαλος, translit=hýalos, lit=crystal, glass, label=none. Histopathology Hyaline cartilage is ...

with the exception of the

caudal fin Fins are distinctive anatomical features composed of bony spines or rays protruding from the body of a fish. They are covered with skin and joined together either in a webbed fashion, as seen in most bony fish, or similar to a flipper, as se ...

which is a dusky yellow with darker edges.

Distribution and habitat

The blackfin scad is distributed throughout parts of the

and

subtropical The subtropical zones or subtropics are geographical zone, geographical and Köppen climate classification, climate zones to the Northern Hemisphere, north and Southern Hemisphere, south of the tropics. Geographically part of the Geographical z ...

region. The species has been recorded as far west as the

Persian Gulf The Persian Gulf ( fa, خلیج فارس, translit=xalij-e fârs, lit=Gulf of Persis, Fars, ), sometimes called the ( ar, اَلْخَلِيْجُ ٱلْعَرَبِيُّ, Al-Khalīj al-ˁArabī), is a Mediterranean sea (oceanography), me ...

(Kuwait) and has a seemingly sparse distribution in the western

Indian Ocean The Indian Ocean is the third-largest of the world's five oceanic divisions, covering or ~19.8% of the water on Earth's surface. It is bounded by Asia to the north, Africa to the west and Australia to the east. To the south it is bounded by th ...

up to

India India, officially the Republic of India (Hindi: ), is a country in South Asia. It is the seventh-largest country by area, the second-most populous country, and the most populous democracy in the world. Bounded by the Indian Ocean on the so ...

and

Sri Lanka Sri Lanka (, ; si, ශ්‍රී ලංකා, Śrī Laṅkā, translit-std=ISO (); ta, இலங்கை, Ilaṅkai, translit-std=ISO ()), formerly known as Ceylon and officially the Democratic Socialist Republic of Sri Lanka, is an ...

. It is common around the

Asia Asia (, ) is one of the world's most notable geographical regions, which is either considered a continent in its own right or a subcontinent of Eurasia, which shares the continental landmass of Afro-Eurasia with Africa. Asia covers an area ...

n coast,

Malaysia Malaysia ( ; ) is a country in Southeast Asia. The federation, federal constitutional monarchy consists of States and federal territories of Malaysia, thirteen states and three federal territories, separated by the South China Sea into two r ...

Philippine The Philippines (; fil, Pilipinas, links=no), officially the Republic of the Philippines ( fil, Republika ng Pilipinas, links=no), * bik, Republika kan Filipinas * ceb, Republika sa Pilipinas * cbk, República de Filipinas * hil, Republ ...

s and as far south as

Indonesia Indonesia, officially the Republic of Indonesia, is a country in Southeast Asia and Oceania between the Indian and Pacific oceans. It consists of over 17,000 islands, including Sumatra, Java, Sulawesi, and parts of Borneo and New Guine ...

. The northernmost captures have been made in Okinawa, Japan and a specimen has also been collected off

Taiwan Taiwan, officially the Republic of China (ROC), is a country in East Asia, at the junction of the East and South China Seas in the northwestern Pacific Ocean, with the People's Republic of China (PRC) to the northwest, Japan to the nort ...

. The species frequents inshore habitats, not found in the open ocean.

Biology and fisheries

The biology and ecology of the blackfin scad are poorly studied, although the diet of the species is known. The species is a

planktivorous A planktivore is an aquatic organism that feeds on planktonic food, including zooplankton and phytoplankton. Planktivorous organisms encompass a range of some of the planet's smallest to largest multicellular animals in both the present day and ...

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

, consuming a variety of pelagic

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

s, prawns and

copepod Copepods (; meaning "oar-feet") are a group of small crustaceans found in nearly every freshwater and saltwater habitat (ecology), habitat. Some species are planktonic (inhabiting sea waters), some are benthos, benthic (living on the ocean floor) ...

s. The species is caught mainly by hook and line methods but is not considered a major commercial species in any regions. Despite this, the fish is highly esteemed in

and Thailand, where it is fried, steamed or

baked Baking is a method of preparing food that uses dry heat, typically in an oven, but can also be done in hot ashes, or on hot stones. The most common baked item is bread but many other types of foods can be baked. Heat is gradually transferre ...

. It may also be salted or

dried Drying is a mass transfer process consisting of the removal of water or another solvent by evaporation from a solid, semi-solid or liquid. This process is often used as a final production step before selling or packaging products. To be consider ...

References

External links

Blackfin scad at fishbase
{{Taxonbar, from=Q2706724 Alepes Fish described in 1839