''Pseudanthias ventralis'', the longfin anthias or longfin basslet', is a species 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 ...

, an Pseudanthias from 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 ...

Anthiinae Anthias are members of the family Serranidae and make up the subfamily Anthiinae. Anthias make up a sizeable portion of the population of pink, orange, and yellow reef fishes seen swarming in most coral reef photography and film. The name Anthi ...

part of 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 ...

Serranidae The Serranidae are a large family of fishes belonging to the order Perciformes. The family contains about 450 species in 65 genera, including the sea basses and the groupers (subfamily Epinephelinae). Although many species are small, in some case ...

, the

grouper Groupers are fish of any of a number of genera in the subfamily Epinephelinae of the family Serranidae, in the order Perciformes. Not all serranids are called "groupers"; the family also includes the sea basses. The common name "grouper" is u ...

s and sea basses. It is found in the Western Pacific Ocean.

Description

''Pseudanthias ventralis'' has males which are metallic purple with a yellow head and a yellow tinge on the back just below the

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 ...

, although sometimes this is masked by heavy purple spotting. The populations from the southern quadrant of their range normally has distinct and circular purple spots in this part of the back. The dorsal fin is red on the spiny part and hyaline or yellowish on the soft-rayed part. 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 ...

is mostly clear and the only markings are two vertical purple lines. The anal fin is clear with an obvious purple line demarcating a are of deeper colouration which contains the anal fin spines and the first soft rays fin. The females are a similar metallic purple colour as the males, but do not have the dame markings. They do have a yellow dorsal fin, the colour just extending on to a small area of the back as far as the caudal peduncle. They also have a red arcing stripe which separates the yellow and purple on the back near the tail. Specimens from other geographical regions show differences in colouration to the above which represents the population from the type locality. The dorsal fin has 10 spines and 17 soft rays while the anal fin has 3 spines and 8 soft rays. This species attains a maximum

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 .

Distribution

''Pseudanthias ventralis'' is found in the Western Pacific from southern Japan to the

Marshall Islands The Marshall Islands ( mh, Ṃajeḷ), officially the Republic of the Marshall Islands ( mh, Aolepān Aorōkin Ṃajeḷ),'' () is an independent island country and microstate near the Equator in the Pacific Ocean, slightly west of the Internati ...

, the

Coral Sea The Coral Sea () is a marginal sea of the South Pacific off the northeast coast of Australia, and classified as an interim Australian bioregion. The Coral Sea extends down the Australian northeast coast. Most of it is protected by the Fre ...

, Vanuatu,

New Caledonia ) , anthem = "" , image_map = New Caledonia on the globe (small islands magnified) (Polynesia centered).svg , map_alt = Location of New Caledonia , map_caption = Location of New Caledonia , mapsize = 290px , subdivision_type = Sovereign st ...

and the

Great Barrier Reef The Great Barrier Reef is the world's largest coral reef system composed of over 2,900 individual reefs and 900 islands stretching for over over an area of approximately . The reef is located in the Coral Sea, off the coast of Queensland, ...

and in

French Polynesia )Territorial motto: ( en, "Great Tahiti of the Golden Haze") , anthem = , song_type = Regional anthem , song = " Ia Ora 'O Tahiti Nui" , image_map = French Polynesia on the globe (French Polynesia centered).svg , map_alt = Location of Frenc ...

Pitcairn Island Pitcairn Island is the only inhabited island of the Pitcairn Islands, of which many inhabitants are descendants of mutineers of HMS ''Bounty''. Geography The island is of volcanic origin, with a rugged cliff coastline. Unlike many other ...

and the

Cook Islands ) , image_map = Cook Islands on the globe (small islands magnified) (Polynesia centered).svg , capital = Avarua , coordinates = , largest_city = Avarua , official_languages = , lan ...

Habitat and biology

''Pseudanthias ventralis'' is associated with coral reefs with a depth range of . It is a secretive species which is normally recorded from caves or beneath ledges but have also been reported over coral rubble along steep drop-offs or the sides of channels. They leave the shelter of caves and overhangs to feed on

zooplankton Zooplankton are the animal component of the planktonic community ("zoo" comes from the Greek word for ''animal''). Plankton are aquatic organisms that are unable to swim effectively against currents, and consequently drift or are carried along by ...

such as

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

. It also feeds on larvae of crustaceans and fish eggs.

Taxonomy

''Pseudanthis ventralis'' was first formally described by John E. Randall as ''Anthias ventralis'' in 1979 with the type locality given as Gannet Ridge near Pitcairn Island. This species is placed in the

subgenus In biology, a subgenus (plural: subgenera) is a taxonomic rank directly below genus. In the International Code of Zoological Nomenclature, a subgeneric name can be used independently or included in a species name, in parentheses, placed between t ...

''Pseudanthias'' by some authorities This species and '' Pseudanthias hawaiiensis'' were formerly considered conspecific but ''P. hawaiiensis'' is now considered a valid species. The variation, especially in males, in different geographic populations of ''P.ventralis'' may warrant further investigation into their specific statuses.

Utilisation

It occasionally makes its way into the aquarium trade, but it is a difficult species to maintain.

References

{{Taxonbar, from=Q3752521 ventralis Fish of the Pacific Ocean Taxa named by John Ernest Randall Fish described in 1979