''Cephalopholis urodeta'', the darkfin hind, flagtail rockcod, chevron rockcod, duskyfin hind, duskyfin rockcod, flagtail grouper or V-tail grouper, 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 ...

, a

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 ...

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 ...

Epinephelinae 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 ...

which is in 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 ...

which also includes the

anthias 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 ...

and sea basses. This fish occurs in 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 far eastern Indian Ocean.

Description

''Cephalopholis urodeta'' has a body which is less deep than the head is long with the body being around a third as deep as the

standard 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 m ...

. The profile between the eyes is convex and the rounded

preopercle The operculum is a series of bones found in bony fish and chimaeras that serves as a facial support structure and a protective covering for the gills; it is also used for respiration and feeding. Anatomy The opercular series contains four bon ...

has a serrated edge and a fleshy lower edge. The

maxilla The maxilla (plural: ''maxillae'' ) in vertebrates is the upper fixed (not fixed in Neopterygii) bone of the jaw formed from the fusion of two maxillary bones. In humans, the upper jaw includes the hard palate in the front of the mouth. The t ...

extends beyond the eye. 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 ...

has 9 spines and 14–16 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 8–9 soft rays. 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 rounded and the

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 do not extend to the anus. The overall colour of this fish is reddish-brown to pale greyish-brown, darkening towards the tail, with obvious whitish to pale blue diagonal lines across both lobes of the caudal fin. They frequently show six faint bars along the flanks, these fork towards the abdomen, and there are small orange-red spots on the head and nape, as well as a pair of dark spots near the tip of the lower lip. The

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 ...

are yellowish and there is normally a large reddish to brownish spot on the edge of the gill cover. This is a small species of grouper which 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

''Cephalopholis urodeta'' is found at

Christmas Island Christmas Island, officially the Territory of Christmas Island, is an Australian external territory comprising the island of the same name. It is located in the Indian Ocean, around south of Java and Sumatra and around north-west of the ...

in the eastern Indian Ocean but it is mainly a species of the Western Pacific Ocean. It extends as far north as

Okinawa is a prefecture of Japan. Okinawa Prefecture is the southernmost and westernmost prefecture of Japan, has a population of 1,457,162 (as of 2 February 2020) and a geographic area of 2,281 km2 (880 sq mi). Naha is the capital and largest city ...

and the

Ryukyu Islands The , also known as the or the , are a chain of Japanese islands that stretch southwest from Kyushu to Taiwan: the Ōsumi, Tokara, Amami, Okinawa, and Sakishima Islands (further divided into the Miyako and Yaeyama Islands), with Yonaguni ...

of southern Japan and as far south as the southern

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, ...

Queensland ) , nickname = Sunshine State , image_map = Queensland in Australia.svg , map_caption = Location of Queensland in Australia , subdivision_type = Country , subdivision_name = Australia , established_title = Before federation , established_ ...

in Australia. Its range extends east as far as

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 ...

and

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 ...

. It has also been recorded from

Phoenix Islands The Phoenix Islands, or Rawaki, are a group of eight atolls and two submerged coral reefs that lie east of the Gilbert Islands and west of the Line Islands in the central Pacific Ocean, north of Samoa. They are part of the Kiribati, Republic ...

Jarvis Island Jarvis Island (; formerly known as Bunker Island or Bunker's Shoal) is an uninhabited coral island located in the South Pacific Ocean, about halfway between Hawaii and the Cook Islands. It is an unincorporated, unorganized territory of the Uni ...

Palmyra Atoll Palmyra Atoll (), also referred to as Palmyra Island, is one of the Line Islands, Northern Line Islands (southeast of Kingman Reef and north of Kiribati). It is located almost due south of the Hawaiian Islands, roughly one-third of the way bet ...

, and

Kingman Reef Kingman Reef is a largely submerged, uninhabited, triangle-shaped reef, geologically an atoll, east-west and north-south, in the North Pacific Ocean, roughly halfway between the Hawaiian Islands and American Samoa. It has an area of 3 hecta ...

, as well as

Brunei Brunei ( , ), formally Brunei Darussalam ( ms, Negara Brunei Darussalam, Jawi alphabet, Jawi: , ), is a country located on the north coast of the island of Borneo in Southeast Asia. Apart from its South China Sea coast, it is completely sur ...

. In 1958 over 1,800 specimens of ''C. urodeta'' sourced in the South Pacific were released near

Oahu Oahu () (Hawaiian language, Hawaiian: ''Oʻahu'' ()), also known as "The Gathering place#Island of Oʻahu as The Gathering Place, Gathering Place", is the third-largest of the Hawaiian Islands. It is home to roughly one million people—over t ...

Hawaii Hawaii ( ; haw, Hawaii or ) is a state in the Western United States, located in the Pacific Ocean about from the U.S. mainland. It is the only U.S. state outside North America, the only state that is an archipelago, and the only stat ...

but they failed to become established.

Habitat and biology

''Cephalopholis urodeta'' is found in clear, shallow waters in the outer areas of reefs, in lagoons, behind the reef and over the top of reefs. They are solitary and prefer healthy coral reefs in areas of shallow water where they feed on largely on small fishes, which make up 68% of its diet, and

crustacean Crustaceans (Crustacea, ) form a large, diverse arthropod taxon which includes such animals as decapods, seed shrimp, branchiopods, fish lice, krill, remipedes, isopods, barnacles, copepods, amphipods and mantis shrimp. The crustacean group ...

s. It occurs down to depths of . A single male will have a territory which includes that of up to six females. The male will court the females in the afternoons.

Taxonomy

This species was once regarded as widespread in the Indian Ocean, nowadays the Indian Ocean form is regarded to be '' Cephalopholis nigripinnis''. The two species are known to hybridise at Christmas Island where intermediate individuals have been recorded.

Utlisation

''Cephalopholis urodeta'' is too small to be of interest to commercial fisheries, although it is taken by subsistence fishermen. It sometimes appears in the

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 ...

trade.

References

External links

* {{Taxonbar, from=Q1906676 urodeta Fish of the Indian Ocean Fish of the Pacific Ocean Fish of Oceania Fish of Palau Least concern biota of Oceania Fish described in 1801 Taxa named by Johann Reinhold Forster