''Acanthurus leucosternon'' is a

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 * ...

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 ...

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 ...

belonging to the

surgeonfish Acanthuridae are the family of surgeonfishes, tangs, and unicornfishes. The family includes about 86 extant species of marine fish living in tropical seas, usually around coral reefs. Many of the species are brightly colored and popular in ...

family Family (from la, familia) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). The purpose of the family is to maintain the well-being of its ...

, Acanthuridae. Its common names are powder blue tang and powder-blue surgeonfish.

Description

The fish can reach an average size of 23 cm (9 in) in length. The body has an oval shape and is compressed laterally. Like other

es, ''Acanthurus leucosternon'' swims with its

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 ...

s. 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 ...

has a crescent shape. The fish has a "surgeon's

scalpel A scalpel, lancet, or bistoury is a small and extremely sharp bladed instrument used for surgery, anatomical dissection, podiatry and various arts and crafts (either called a hobby knife or an X-acto knife.). Scalpels may be single-use disposa ...

," an erected part of the spine located at the base of the tail. The mouth is small and pointed in a beak-like manner with tiny and sharp teeth for reaching narrow spaces of food. Its sides are blue; its

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 ...

and the base of

are yellow; the head is black; the mouth, the throat area, the

anal Anal may refer to: Related to the anus *Related to the anus of animals: ** Anal fin, in fish anatomy ** Anal vein, in insect anatomy ** Anal scale, in reptile anatomy *Related to the human anus: ** Anal sex, a type of sexual activity involvin ...

and

pelvic fin Pelvic fins or ventral fins are paired fins located on the ventral surface of fish. The paired pelvic fins are homologous to the hindlimbs of tetrapods. Structure and function Structure In actinopterygians, the pelvic fin consists of two en ...

s are white. The

s are transparent with yellow reflections. The intensity of its blue color shows off if the fish is healthy or not. The fish does not undergo color changes as it matures; as some tangs, surgeonfish and unicornfish do.

Distribution and habitat

''Acanthurus leucosternon'' is found in tropical waters from the

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 ...

. The

species In biology, a species is the basic unit of classification and a taxonomic rank of an organism, as well as a unit of biodiversity. A species is often defined as the largest group of organisms in which any two individuals of the appropriate s ...

inhabits shallow and clear coastal waters always associated with a

reef A reef is a ridge or shoal of rock, coral or similar relatively stable material, lying beneath the surface of a natural body of water. Many reefs result from natural, abiotic processes— deposition of sand, wave erosion planing down rock out ...

. It prefers flat top reefs and areas along seaward slopes.

Behaviour

The powder blue tang, like most

in the family

Acanthuridae Acanthuridae are the family of surgeonfishes, tangs, and unicornfishes. The family includes about 86 extant species of marine fish living in tropical seas, usually around coral reefs. Many of the species are brightly colored and popular in aq ...

, is

herbivorous A herbivore is an animal anatomically and physiologically adapted to eating plant material, for example foliage or marine algae, for the main component of its diet. As a result of their plant diet, herbivorous animals typically have mouthpart ...

, eating mostly

benthic The benthic zone is the ecological region at the lowest level of a body of water such as an ocean, lake, or stream, including the sediment surface and some sub-surface layers. The name comes from ancient Greek, βένθος (bénthos), meaning "t ...

algae Algae (; singular alga ) is an informal term for a large and diverse group of photosynthetic eukaryotic organisms. It is a polyphyletic grouping that includes species from multiple distinct clades. Included organisms range from unicellular mic ...

. ''Acanthurus leucosternon'' has a diurnal activity. It is

solitary Solitary is the state of being alone or in solitude. The term may refer to: * shortened form of solitary confinement * Solitary animal, an animal that does not live with others in its species * Solitary but social, a type of social organization in ...

territorial A territory is an area of land, sea, or space, particularly belonging or connected to a country, person, or animal. In international politics, a territory is usually either the total area from which a state may extract power resources or a ...

and aggressive with other

. In cases where food is plentiful, it may feed in shoals, but in cases of scarcity, it may compete individually for food. It may use its surgeon's

as a defensive weapon.

Economic value

Maldives Surgeonfish, Acanthurus leucosternon

The powder blue tang is rarely harvested for anything other than the marine

aquarium An aquarium (plural: ''aquariums'' or ''aquaria'') is a vivarium of any size having at least one transparent side in which aquatic plants or animals are kept and displayed. Fishkeepers use aquaria to keep fish, invertebrates, amphibians, aq ...

industry. It is a commonly sold fish that is moderately difficult to care for, although its popularity is easily exceeded by the

regal tang ''Paracanthurus hepatus'' is a species of Indo-Pacific surgeonfish. A popular fish in marine aquaria, it is the only member of the genus ''Paracanthurus''. A number of common names are attributed to the species, including regal tang, palette s ...

and

yellow tang The yellow tang (''Zebrasoma flavescens'') is a saltwater fish species of the family Acanthuridae. It is one of the most popular marine aquarium fish. It is bright yellow in color, and it lives in reefs. The yellow tang spawn around a full mo ...

. They are very prone to ''

Cryptocaryon irritans ''Cryptocaryon irritans'' is a species of ciliates that parasitizes marine fish, causing marine white spot disease or marine ich (pronounced ''ick''). It is one of the most common causes of disease in marine aquaria. Taxonomy ''Cryptocaryon i ...

''. They are reef safe and are compatible with most species except other species of fish in the genus

Acanthurus ''Acanthurus'' is a genus of fish in the family Acanthuridae found in the Atlantic, Indian and Pacific Ocean. They are found in tropical oceans, especially near coral reefs, with most species in the Indo-Pacific but a few are found in the Atla ...

References

External links