Twospot Bristletooth, Ctenochaetus binotatus Randall 1955

Other Names: Two-spot Bristletooth, Two-spot Bristle-tooth, Twospot Surgeonfish

A Twospot Bristletooth, Ctenochaetus binotatus, on Ribbon Reef #10, Great Barrier Reef, Queensland, June 2002. Source: Erik Schlogl / License: CC by Attribution-NonCommercial

A brown surgenfish with pale spots on the head and chest, pale lines along the side, a blue eye, a conspicuous dark spot at the rear base of the dorsal and anal fins, and a lunate tail.

Cite this page as:
Bray, D.J. 2018, Ctenochaetus binotatus in Fishes of Australia, accessed 29 Mar 2023,

Twospot Bristletooth, Ctenochaetus binotatus Randall 1955

More Info


Offshore reefs of Western Australia, Ashmore Reef, Timor Sea, and the far northern Great Barrier Reef to One Tree Island, Capricorn Group, Queensland, with juveniles to at least Jervis Bay, New South Wales; also reefs in the Coral Sea. 
Elsewhere the species is widespread in the Indo-Pacific from East Africa to the Tuamoto archipelago and Mangareva, northwards to southern Japan, and south to Sydney and the Lord Howe Island region.


Species of Ctenochaetus feed on fine detritus, whisking the sand or rocky substrates with their teeth and sucking up detritus that comprises diatoms, small fragments of algae, organic material and fine inorganic sediment.

Similar Species

Similar surgeonfish such as the Lined Bristletooth, Ctenochaetus striatus, the Yelloweye Bristletooth, C. cyanocheilus, and the Dusky Surgeonfish, Acanthurus nigrofuscus, lack the blue eye ring.

Species Citation

Ctenochaetus binotatus Randall 1955, Zoologica (New York) 40(4): 164, text fig. 1G. Type locality: Pagapas Bay, Luzon, Philippines. 


Bray, D.J. 2018


Australian Faunal Directory

Twospot Bristletooth, Ctenochaetus binotatus Randall 1955


Allen, G.R. 1993. Fishes of Ashmore Reef and Cartier Island. Records of the Western Australian Museum, Supplement 44: 67-91 

Allen, G.R. 1997. Marine Fishes of Tropical Australia and South-east Asia. Perth : Western Australian Museum 292 pp. 106 pls. 

Allen, G.R. & Erdmann, M.V. 2012. Reef fishes of the East Indies. Perth : Tropical Reef Research 3 vols, 1260 pp. 

Allen, G.R. & Russell, B.C. 1986. Part VII Fishes. pp. 79-103 in Berry, P.F. (ed.). Faunal Surveys of the Rowley Shoals, Scott Reef and Seringapatam Reef, northwestern Australia. Records of the Western Australian Museum, Supplement 25: 1-106

Choat, J.H., Clements, K.D. and Robbins, W.D. 2002b. The trophic status of herbivorous fishes on coral reefs. 1. Dietary analyses. Marine Biology 140: 613-623.

Clements, K.D., Choat, J.H., Abesamis, R., McIlwain, J., Myers, R., Nanola, C., Rocha, L.A., Russell, B. & Stockwell, B. 2012. Ctenochaetus binotatus. The IUCN Red List of Threatened Species 2012: e.T177955A1501829. Downloaded on 25 January 2018.

Hutchins, J.B. 2001. Biodiversity of shallow reef fish assemblages in Western Australia using a rapid censusing technique. Records of the Western Australian Museum 20: 247-270 

Kuiter, R.H. 1992. Tropical Reef-Fishes of the Western Pacific, Indonesia and Adjacent Waters. Jakarta : PT Gramedia Pustaka Utama 314 pp. pls. 

Kuiter, R.H. 1993. Coastal Fishes of South-eastern Australia. Bathurst : Crawford House Press 437 pp. 

Kuiter, R.H. & Debelius, H. 2001. Surgeonfishes, Rabbitfishes and Their Relatives. A comprehensive guide to Acanthuroidei. Chorleywood, U.K. : TMC Publishing 208 pp. 

Lou, D.C. 1993. Growth in juvenile Scarus rivulatus and Ctenochaetus binotatus: a comparison of families Scaridae and Acanthuridae. Journal of Fish Biology 42: 15-23.

Lou, D.C. & Moltschaniwskyj, N. 1992. Daily otolith increments in juvenile tropical parrotfishes and surgeonfishes, Australian Journal of Marine and Freshwater Research 43: 973-981.

Oxley, W.G., Emslie, M., Muir, P. & Thompson, A.A. 2004. Marine surveys undertaken in the Lihou Reef National Nature Reserve, March 2004. Townsville : Australian Institute of Marine Science i-vii, 1-67 pp. 

Randall, J.E. 1955. A revision of the surgeonfish genus Ctenochaetus, family Acanthuridae, with descriptions of five new species. Zoologica (New York) 40(4): 149-166 figs 1-3 pls 1-2 

Randall, J.E. 2001. Surgeonfishes of Hawai'i and the World. Honolulu : Mutual Publishing and Bishop Museum Press 125 pp. 

Randall, J.E., Allen, G.R. & Steene, R. 1990. Fishes of the Great Barrier Reef and Coral Sea. Bathurst : Crawford House Press 507 pp. figs. 

Randall, J.E., Allen, G.R. & Steene, R. 1997. Fishes of the Great Barrier Reef and Coral Sea. Bathurst : Crawford House Press 557 pp. figs. 

Randall, J.E & Clements, K.D. 2001. Second revision of the surgeonfish genus Ctenochaetus (Perciformes: Acanthuridae), with descriptions of two new species. Indo-Pacific Fishes 32: 33.

Russell, B.C. 1983. Annotated checklist of the coral reef fishes in the Capricorn-Bunker group, Great Barrier Reef, Australia. Great Barrier Reef Marine Park Authority. Special Publication Series 1: 1-184 figs 1-2 

Russell, B.C., Larson, H.K., Hutchins, J.B. & Allen, G.R. 2005. Reef fishes of the Sahul Shelf. The Beagle, Records of the Museums and Art Galleries of the Northern Territory Supplement 1 2005: 83-105

Quick Facts

CAAB Code:37437021

Conservation:IUCN Least Concern

Depth:2-55 m

Fishing:Aquarium fish

Habitat:Reef associated

Max Size:22 cm TL

Species Maps

CAAB distribution map