''Acanthurus nubilus'', the bluelined surgeon, pin-striped surgeon, dark surgeonfish or dropoff surgeonfish, 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 ...

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 ...

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 ...

, which includes the surgeonfishes, unicornfishes and tangs. This species is found in the Western Pacific Ocean.

Taxonomy

''Acanthurus nubilus'' was first formally described as ''Hepatus nubilus'' in 1929 by the American

ichthyologist Ichthyology is the branch of zoology devoted to the study of fish, including bony fish ( Osteichthyes), cartilaginous fish (Chondrichthyes), and jawless fish (Agnatha). According to FishBase, 33,400 species of fish had been described as of Octobe ...

Henry Weed Fowler Henry Weed Fowler (March 23, 1878 – June 21, 1965) was an American zoologist born in Holmesburg, Pennsylvania. He studied at Stanford University under David Starr Jordan. He joined the Academy of Natural Sciences in Philadelphia and worked as ...

and Barton Appler Bean with its type locality given as Dodepo Island on the

Gulf of Tomini The Gulf of Tomini ( id, Teluk Tomini), also known as the Bay of Tomini, is the equatorial gulf which separates the Minahassa Peninsula, Minahassa (Northern) and East Peninsula, Sulawesi, East Peninsulas of the island of Sulawesi (Celebes) in In ...

off

Sulawesi Sulawesi (), also known as Celebes (), is an island in Indonesia. One of the four Greater Sunda Islands, and the world's eleventh-largest island, it is situated east of Borneo, west of the Maluku Islands, and south of Mindanao and the Sulu Ar ...

. The genus '' Acanthurus'' is one of two genera in the tribe Acanthurini which is one of three tribes in 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 ...

Acanthurinae ''Acanthurinae'' is a subfamily of fish belonging to the family Acanthuridae, including 55 species in four genera. Description Among the species of the genera ''Acanthurus'' and ''Zebrasoma'' there are small anatomical differences: the fir ...

which is one of two subfamilies in the family Acanthuridae.

Etymology

''Acanthurus nubilus'' has the specific name ''nubilus'', which means "cloudy", and is a reference to the overall dull dark colour of this fish with dusky median and pelvic fins.

Description

''Acanthurus nubilus'' has 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 ...

supported by 6 or 7 spines and between 25 and 27 soft rays while ythe

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 ...

is supported by 3 spines and 23 or 24 soft rays. The head and front part of the body are bluish-grey with many dense brown or brownish-yellow spots, which change into horizontal lines towards the rear of the body. This species has a maximum published

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 and habitat

''Acanthurus nubilus'' is found in the western Pacific Ocean where it has been recorded from Indonesia, the

Society Islands The Society Islands (french: Îles de la Société, officially ''Archipel de la Société;'' ty, Tōtaiete mā) are an archipelago located in the South Pacific Ocean. Politically, they are part of French Polynesia, an overseas country of the F ...

and the

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 has been reported from the

Austral Islands The Austral Islands (french: Îles Australes, officially ''Archipel des Australes;'' ty, Tuha'a Pae) are the southernmost group of islands in French Polynesia, an overseas country of the French Republic in the South Pacific. Geographically, ...

Pitcairn Islands The Pitcairn Islands (; Pitkern: '), officially the Pitcairn, Henderson, Ducie and Oeno Islands, is a group of four volcanic islands in the southern Pacific Ocean that form the sole British Overseas Territory in the Pacific Ocean. The four isl ...

, the Philippines and the

Marianas The Mariana Islands (; also the Marianas; in Chamorro: ''Manislan Mariånas'') are a crescent-shaped archipelago comprising the summits of fifteen longitudinally oriented, mostly dormant volcanic mountains in the northwestern Pacific Ocean, betw ...

. It is found at depths between on steep drop offs exposed to strong currents where it 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 ...

References

{{Taxonbar, from=Q1094321 nubilis Fish described in 1929 Taxa named by Henry Weed Fowler Taxa named by Barton Appler Bean