''Apsilus'' is a small

genus Genus ( plural genera ) is a taxonomic rank used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In the hierarchy of biological classification, genus com ...

of marine

ray-finned fish Actinopterygii (; ), members of which are known as ray-finned fishes, is a class of bony fish. They comprise over 50% of living vertebrate species. The ray-finned fishes are so called because their fins are webs of skin supported by bony or hor ...

, snappers belonging to the

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 ...

Lutjanidae Lutjanidae, or snappers are a family of perciform fish, mainly marine, but with some members inhabiting estuaries, feeding in fresh water. The family includes about 113 species. Some are important food fish. One of the best known is the red snapp ...

. The two species within the genus are native to the

Atlantic Ocean The Atlantic Ocean is the second-largest of the world's five oceans, with an area of about . It covers approximately 20% of Earth's surface and about 29% of its water surface area. It is known to separate the " Old World" of Africa, Europe ...

Characteristics

The two species within the genus ''Apsilus'' are medium-sized snappers with

fusiform Fusiform means having a spindle-like shape that is wide in the middle and tapers at both ends. It is similar to the lemon-shape, but often implies a focal broadening of a structure that continues from one or both ends, such as an aneurysm on a b ...

bodies, the body can be slender or relatively deep but these are robust fishes. The jaws are equipped with moderately sized teeth which are conical or bristle shaped and which are arranged in bands with the outer row enlarged. They have a continuous

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 ...

which is not notched where the spiny and soft-rayed parts meet. The dorsal fin has 10 spines and 9 or 10 soft rays while 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 ...

has 3 spines and 8 soft rays. The dorsal and anal fins are lacking in scales while the caudal fin is scaled, the caudal fin may be forked or emarginate.

Distribution

''Apsilus'' fishes are found in the Atlantic Ocean, the African forktail snapper has been reported from the Indian Ocean but these reports are questionable.

Habitat and biology

''Apsilus'' snappers inhabit waters with depths between , typically over rocky substrates. They may be encountered as solitary fish or in aggregations and they feed on small fish, squid, benthic crustaceans and more sizeable zooplankton.

Species

The following currently recognized species make up the genus ''Apsilus'': * ''

Apsilus dentatus ''Apsilus dentatus'', the black snapper, is a species of marine ray-finned fish, a snapper belonging to the Family (biology), family Lutjanidae. It is found in the western Atlantic Ocean. Description ''Apsilus dentatus'' has an elongated, oval sha ...

'' Guichenot, 1853 (black snapper) * '' Apsilus fuscus'' Valenciennes, 1830 (African forktail snapper)

Systematics and etymology

''Apsilus'' was created in 1830 when the French

zoologist Zoology ()The pronunciation of zoology as is usually regarded as nonstandard, though it is not uncommon. is the branch of biology that studies the Animal, animal kingdom, including the anatomy, structure, embryology, evolution, Biological clas ...

Achille Valenciennes described ''A. fuscus'' from the Cape Verde Islands. In 1980 when G. David Johnson designated the

subfamily In biological classification, a subfamily (Latin: ', plural ') is an auxiliary (intermediate) taxonomic rank, next below family but more inclusive than genus. Standard nomenclature rules end subfamily botanical names with "-oideae", and zoologi ...

Apsilinae Apsilinae is a subfamily of marine ray-finned fishes, one of four subfamilies classified within the family Lutjanidae, the snappers. Genera The subfamily Apsilinae contains four genera and 13 species: * '' Apsilus'' Valenciennes, 1230 * '' Lipo ...

within the Lutjanidae he used ''Apsilus'' as its type genus. ''Apsilus''is formed the word ''a'' meaning "not" and ''psilos'' meaning ''naked'' or ''bald'', Valenciennes did not explain what this name alludes to but these fishes have scales on 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 ...

, but none of the other fins are scaled.

References

{{Taxonbar, from=Q10416303 Apsilinae