''Ctenochaetus'', or bristletooth tangs, is a

genus Genus (; : genera ) is a taxonomic rank above species and below family (taxonomy), family as used in the biological classification of extant taxon, living and fossil organisms as well as Virus classification#ICTV classification, viruses. In bino ...

of marine

ray-finned fish Actinopterygii (; ), members of which are known as ray-finned fish or actinopterygians, is a class of bony fish that comprise over 50% of living vertebrate species. They are so called because of their lightly built fins made of webbings of sk ...

belonging to the

family Family (from ) is a Social group, group of people related either by consanguinity (by recognized birth) or Affinity (law), affinity (by marriage or other relationship). It forms the basis for social order. Ideally, families offer predictabili ...

Acanthuridae Acanthuridae are a family of ray-finned fish which includes 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 brigh ...

, which includes the surgeonfishes, unicornfishes and tangs. These fishes are found in the

Indo-Pacific The Indo-Pacific is a vast biogeographic region of Earth. In a narrow sense, sometimes known as the Indo-West Pacific or Indo-Pacific Asia, it comprises the tropical waters of the Indian Ocean, the western and central Pacific Ocean, and the ...

region. They have many, small flexible teeth and some species have the common name bristletooth.

Taxonomy

''Ctenochaetus'' was first proposed as a genus in 1884 by the American

biologist A biologist is a scientist who conducts research in biology. Biologists are interested in studying life on Earth, whether it is an individual Cell (biology), cell, a multicellular organism, or a Community (ecology), community of Biological inter ...

Theodore Gill Theodore Nicholas Gill (March 21, 1837 – September 25, 1914) was an American ichthyologist, mammalogist, malacologist, and librarian. Career Born and educated in New York City under private tutors, Gill early showed interest in natural hist ...

with ''Acanthurus strigosus'' as its

type species In International_Code_of_Zoological_Nomenclature, zoological nomenclature, a type species (''species typica'') is the species name with which the name of a genus or subgenus is considered to be permanently taxonomically associated, i.e., the spe ...

. ''A. strigosus'' had originally been described in 1828 by

Edward Turner Bennett Edward Turner Bennett (6 January 1797 – 21 August 1836) was an English zoologist and writer. He was the elder brother of the botanist John Joseph Bennett.

from the Sandwich Islands.

Paraphyly

It has been proposed that this genus and ''

Acanthurus ''Acanthurus'' is a genus of marine ray-finned fish belonging to the family Acanthuridae, which includes the surgeonfishes, unicornfishes and tangs, found in the Atlantic, Indian and Pacific Ocean. They are found in tropical oceans, especially ...

'' should be merged as otherwise ''Acanthurus'' is

paraphyletic Paraphyly is a taxonomic term describing a grouping that consists of the grouping's last common ancestor and some but not all of its descendant lineages. The grouping is said to be paraphyletic ''with respect to'' the excluded subgroups. In co ...

. ''Ctenochaetus'' species all nest within ''Acanthurus'', while '' A. nubilis'' and '' A. pyroferus'' are furthermore nested within ''Ctenochaetus''. The 5th edition of ''

Fishes of the World ''Fishes of the World'' is a standard reference for the systematics of fishes. It was first written in 1976 by the American ichthyologist Joseph S. Nelson (1937–2011). Now in its fifth edition (2016), the work is a comprehensive overview of t ...

'' recognises these two genera as valid and classifies them as the two genera in the

tribe The term tribe is used in many different contexts to refer to a category of human social group. The predominant worldwide use of the term in English is in the discipline of anthropology. The definition is contested, in part due to conflict ...

Acanthurini of 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 botanical subfamily names with "-oideae", and zo ...

Acanthurinae within the family Acanthuridae.

Etymology

''Ctenochaetus'' Is a compound of ''cteno'', meaning “bristle”, and ''chaetus'', meaning “comb”. Gill did not explain what this alluded to but it is almost certain to allude to the bristle or comb like teeth of these fishes.

Species

''Ctenochaetus'' currently has nine recognised species classified within it: * '' Ctenochaetus binotatus'' J. E. Randall, 1955 (Twospot surgeonfish) * '' Ctenochaetus cyanocheilus'' J. E. Randall & Clements, 2001 (Short-tail bristle-tooth) * '' Ctenochaetus flavicauda'' Fowler, 1938 (Whitetail bristletooth) * '' Ctenochaetus hawaiiensis'' J. E. Randall, 1955 (Chevron tang) * '' Ctenochaetus marginatus'' (

Valenciennes Valenciennes (, also , , ; ; or ; ) is a communes of France, commune in the Nord (French department), Nord Departments of France, department, Hauts-de-France, France. It lies on the Scheldt () river. Although the city and region experienced ...

, 1835) (Striped-fin surgeonfish) * '' Ctenochaetus striatus'' ( Quoy &

Gaimard Joseph Paul Gaimard (31 January 1793 – 10 December 1858) was a French naval surgeon and naturalist. Biography Gaimard was born at Saint-Zacharie on January 31, 1793. He studied medicine at the naval medical school in Toulon, subsequent ...

, 1825) (Striated surgeonfish) * '' Ctenochaetus strigosus'' ( E. T. Bennett, 1828) (Kole Tang) * '' Ctenochaetus tominiensis'' J. E. Randall, 1955 (Tomini surgeonfish) * '' Ctenochaetus truncatus'' J. E. Randall & Clements, 2001 (Indian gold-ring bristle-tooth)

Characteristics

''Ctenochaetus'' surgeonfishes are closely related to the surgeonfishes in the genus ''Acanthurus'' and are very similar to them. They have a different jaw structure from the ''Acanthurus'' surgeonfishes having numerous brush or bristle like flexible teeth. Their

dorsal fin A dorsal fin is a fin on the back of most marine and freshwater vertebrates. Dorsal fins have evolved independently several times through convergent evolution adapting to marine environments, so the fins are not all homologous. They are found ...

is supported by 8 spines and between 24 and 31 soft rays while their

anal fin Fins are moving appendages protruding from the body of fish that interact with water to generate thrust and help the fish swim. Apart from the tail or caudal fin, fish fins have no direct connection with the back bone and are supported o ...

s are supported by 3 spines and between 22 and 28 soft rays. These fish vary in length from a maximum published

standard length Fish measurement is the measuring of individual fish and various parts of fish anatomy, their anatomies, for data used in many areas of ichthyology, including Taxonomy (biology), taxonomy and fishery biology. Overall length Standard length (SL) is ...

of in ''C. strigosus'' to a maximum published

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

of in ''C. marginatus''.

Distribution

''Ctenochaetus'' surgeonfishes have a wide Indo-Pacific distribution. They are found from the eastern coast of Africa, including the Red Sea eastwards through the tropical Indian Ocean into the Pacific Ocean as far east as

Hawaii Hawaii ( ; ) is an island U.S. state, state of the United States, in the Pacific Ocean about southwest of the U.S. mainland. One of the two Non-contiguous United States, non-contiguous U.S. states (along with Alaska), it is the only sta ...

References

{{Taxonbar, from=Q137748 Acanthurini Marine fish genera Taxa named by Theodore Gill Taxa described in 1884