''Monacanthus chinensis'', commonly known as the fan-bellied leatherjacket or fantail leatherjacket, is a

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 ...

filefish The filefish (Monacanthidae) are a diverse family of tropical to subtropical tetraodontiform marine fish, which are also known as foolfish, leatherjackets or shingles. They live in the Atlantic, Pacific and Indian Oceans. Filefish are closely rel ...

native to the western

Pacific Ocean The Pacific Ocean is the largest and deepest of Earth's five oceanic divisions. It extends from the Arctic Ocean in the north to the Southern Ocean (or, depending on definition, to Antarctica) in the south, and is bounded by the continen ...

and the eastern

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 ...

where it is found on

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 ...

s and soft sediments at shallow depths. This species grows to a

total length Fish measurement is the measuring of individual fish and various parts of their anatomies. These data are used in many areas of ichthyology, including taxonomy and fisheries biology. Overall length * Standard length (SL) is the length of a fish ...

of .

Description

The fan-bellied leatherjacket grows to a total length of about . It is a laterally-compressed fish recognisable by the upturned, pointed snout, the filamentary extension on the fan-shaped caudal fin, and the large dewlap on the underside of the fish. The foremost dorsal fin consists of a long erectile spine with a shorter one behind it. The hindermost dorsal fin has 28 to 34 soft rays and the anal fin has 27 to 34 soft rays. The colour is variable depending on its environment, being dark when swimming over beds of

mussel Mussel () is the common name used for members of several families of bivalve molluscs, from saltwater and Freshwater bivalve, freshwater habitats. These groups have in common a shell whose outline is elongated and asymmetrical compared with other ...

s and cream or tan when above a sandy seabed. In each case there are irregular darker blotches and streaks.

Distribution and habitat

The fan-bellied leatherjacket is native to the Indo-Pacific. Its range extends from Malaysia and southern Japan, through Indonesia and Samoa to western, northern and eastern Australia. It is a

demersal The demersal zone is the part of the sea or ocean (or deep lake) consisting of the part of the water column near to (and significantly affected by) the seabed and the benthos. The demersal zone is just above the benthic zone and forms a layer of ...

species and is found in estuaries and on algae-clad rocky coasts as well as over muddy and silty seabeds, on

seagrass meadow A seagrass meadow or seagrass bed is an underwater ecosystem formed by seagrasses. Seagrasses are marine (saltwater) plants found in shallow coastal waters and in the brackish waters of estuaries. Seagrasses are flowering plants with stems and ...

s and on reefs, both on and offshore, to depths of about .

Biology

The fan-bellied leatherjacket is diurnal and omnivorous, appearing to detect its food by sight. Besides feeding on

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 ...

and

seagrass Seagrasses are the only flowering plants which grow in marine environments. There are about 60 species of fully marine seagrasses which belong to four families (Posidoniaceae, Zosteraceae, Hydrocharitaceae and Cymodoceaceae), all in the orde ...

, it

preys 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 ...

on small invertebrates such as amphipods, caridean shrimps,

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, tanaids,

bryozoa Bryozoa (also known as the Polyzoa, Ectoprocta or commonly as moss animals) are a phylum of simple, aquatic invertebrate animals, nearly all living in sedentary colonies. Typically about long, they have a special feeding structure called a l ...

ns, hydroids,

polychaete worms Polychaeta () is a paraphyletic class of generally marine annelid worms, commonly called bristle worms or polychaetes (). Each body segment has a pair of fleshy protrusions called parapodia that bear many bristles, called chaetae, which are m ...

and

tunicate A tunicate is a marine invertebrate animal, a member of the subphylum Tunicata (). It is part of the Chordata, a phylum which includes all animals with dorsal nerve cords and notochords (including vertebrates). The subphylum was at one time ca ...

s. It does not appear to digest seagrass and algae well, but nevertheless, many carbon compounds are assimilated from these foodstuffs during the digestion process. About 40% of the diet is animal matter, and this species is very dependent on encrusting organisms and the

epiphytic An epiphyte is an organism that grows on the surface of a plant and derives its moisture and nutrients from the air, rain, water (in marine environments) or from debris accumulating around it. The plants on which epiphytes grow are called phoroph ...

algae and invertebrates present in a seagrass meadow.

References

External links

* {{Taxonbar, from=Q2650327 Monacanthidae Taxa named by Pehr Osbeck Fish described in 1765