Steephead Parrotfish, Chlorurus microrhinos (Bleeker 1854)

Other Names: Blunt-head Parrotfish, Gibbus Parrotfish, Heavybeak Parrotfish, Pacific Steephead Parrotfish

A male Steephead Parrotfish, Chlorurus microrhinos, in the Abrolhos Islands, Western Australia. Source: Rick Stuart-Smith / Reef Life Survey. License: CC by Attribution


This large parrotfish plays a very important role on coral reefs. As they graze schools of Steephead Parrotfish excavate coral to remove algae.

Footage of a Steephead Parrotfish sleeping in its protective mucus shield.

Cite this page as:
Bray, D.J. 2020, Chlorurus microrhinos in Fishes of Australia, accessed 24 Jun 2024,

Steephead Parrotfish, Chlorurus microrhinos (Bleeker 1854)

More Info


Rottnest Island to north Western Australia including offshore reefs, Ashmore Reef in the Timor Sea, the Northern Territory, and the far northern Great Barrier Reef and reefs in the Coral Sea, to Sydney, New South Wales; also Christmas Island in the eastern Indian Ocean, and the Lord Howe Island region in the Tasman Sea. Elsewhere the species is widespread in the east-Indo-west-central Pacific. Occurs in habitats ranging from inshore reefs to exposed outer reefs, forming schools of up to 40 individuals on reef fronts and reef crests.
This species is the most abundant large parrotfish marine parks in Western Australia and Queensland.


Feeds on benthic turf algae and detritus obtained by crunching dead coral on the reef.


A fast growing species, attaining a maximum age of 15 years.


This large parrotfish is targeted for food in much of its range, and is heavily fished in some areas.


In a recent study of steephead parrotfish on the Great Barrier Reef, tagged individuals had their internal temperatures monitored for a 24 h period using active acoustic telemetry. At night, on the reef, C. microrhinos were found to maintain a consistent average peritoneal cavity temperature 0.16 +/- 0.005°C (SE) warmer than the ambient temperature of the surrounding water (Welsh et al. 2012).

Species Citation

Scarus microrhinos Bleeker 1854, Natuurkundig Tijdschrift voor Nederlandsch Indië 6: 200. Type locality: Jakarta (as Batavia), Indonesia.


Bray, D.J. 2020


Atlas of Living Australia

Steephead Parrotfish, Chlorurus microrhinos (Bleeker 1854)


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. 2000. Fishes of Christmas Island, Indian Ocean. Records of the Western Australian Museum Supplement 59: 83-95.

Allen, G.R., Hoese, D.F., Paxton, J.R., Randall, J.E., Russell, B.C., Starck, W.A., Talbot, F.H. & Whitley, G.P. 1976. Annotated checklist of the fishes of Lord Howe Island. Records of the Australian Museum 30(15): 365-454 figs 1-2 

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

Allen, G.R., Steene, R.C. & Orchard, M. 2007. Fishes of Christmas Island. Christmas Island : Christmas Island Natural History Association 2 edn, 284 pp. 

Bellwood, D.R. 1994. A phylogenetic study of the parrotfishes family Scaridae (Pisces: Labroidei), with a revision of genera. Records of the Australian Museum, Supplement 20: 1-86 (as Chlorurus gibbus)

Bellwood, D.R. 1996. Coral reef crunchers. Nature Australia Autumn: 48-55.

Bellwood, D.R. 2001. Scaridae. pp. 3468-3492 in Carpenter, K.E. & Niem, T.H. (eds). The Living Marine Resources of the Western Central Pacific. FAO Species Identification Guide for Fisheries Purposes. Rome : FAO Vol. 6 pp. 3381-4218.

Bleeker, P. 1854. Species piscium batabiensium novae vel minus cognitae. Natuurkundig Tijdschrift voor Nederlandsch Indië 6: 191-202 See ref at BHL

Ceccarelli, D., Choat, J.H., Ayling, A.M., Richards, Z., van Herwerden, L., Ayling, A., Ewels, G., Hobbs, J. –P. & Cuff, B. 2008. Coringa-Herald National Nature Reserve Marine Survey – 2007. Report to the Department of the Environment, Water, Heritage and the Arts by C&R Consulting and James Cook University. 80 pp.

Choat, J.H., Axe, L.M. & Lou, D.C. 1996. Growth and longevity in fishes of the family Scaridae. Marine Ecology Progress Series 145: 33-41 (as Chlorurus gibbus)

Choat, J.H., Carpenter, K.E., Clements, K.D., Rocha, L.A., Russell, B., Myers, R., Lazuardi, M.E., Muljadi, A., Pardede, S. & Rahardjo, P. 2012. chlorurus microhinos. The IUCN Red List of Threatened Species 2012: e.T190728A17783512. Downloaded on 02 August 2016.

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

Choat, J.H., Clements, K.D. & Robbins, W.D. 2004. The trophic status of herbivorous fishes on coral reefs 2: Food processing modes and trophodynamics. Marine Biology 145: 445-454

Choat, J.H., Klanten, O.S., van Herwerden, L., Robertson, D.R. & Clements, K.D. 2012. Patterns and processes in the evolutionary history of parrotfishes (Family Labridae). Biological Journal of the Linnean Society 107: 529-557.

Choat, J.H. & Randall, J.E. 1986. A review of the parrotfishes (family Scaridae) of the Great Barrier Reef of Australia with description of a new species. Records of the Australian Museum 38: 175-228. (as Scarus gibbus)

Clements, K.D., German, D.P., Piché, J., Tribollet, A. & Choat, J.H. 2016. Integrating ecological roles and trophic diversification on coral reefs: multiple lines of evidence identify parrotfishes as microphages. Biological Journal of the Linnean Society

Choat, J.H., van Herwerden, L., Robbins, W.D., Hobbs, J.P. & Ayling, A.M. 2006. A report on the ecological surveys undertaken at Middleton and Elizabeth Reefs, February 2006. Report by James Cook University to the Department of the Environment and Heritage. 65 pp.

Comeros-Raynal, M.T., Choat, J.H., Polidoro, B.A., Clements, K.D., Abesamis, R., Craig, M.T., Lazuardi, M.E., McIlwain, J., Muljadi, A., Myers, R.F., Nañola Jr., C.L., Pardede, S., Rocha, L.A., Russell, B., Sanciangco, J.C., Stockwell, B., Harwell, H. & Carpenter, K.E. 2012. The likelihood of extinction of iconic and dominant components of coral reefs: the parrotfishes and surgeonfishes. PLoS ONE

Crossman, D.J., Choat, J.H. & Clements, K.D. 2005. Nutritional ecology of nominally herbivorous fishes on coral reefs. Marine Ecology Progress Series 296: 129-142.

Francis, M.P. 1993. Checklist of the coastal fishes of Lord Howe, Norfolk, and Kermadec Island, southwest Pacific Ocean. Pacific Science 47(2): 136-170

Gill, A.C. & Reader, S.E. 1992. Fishes. pp. 90-93, 193-228 in Hutchings, P. (ed.) Reef Biology. A Survey of Elizabeth and Middleton Reefs, South Pacific. Canberra : Australian National Parks Vol. 3, Kowari 230 pp. 

Hobbs, J-P.A., Newman, S.J., Mitsopoulos, G.E.A., Travers, M.J., Skepper, C.L., Gilligan, J.J., Allen, G.R., Choat, H.J. & Ayling, A.M. 2014. Checklist and new records of Christmas Island fishes: the influence of isolation, biogeography and habitat availability on species abundance and community composition. Raffles Bulletin of Zoology Supplement 30: 184–202

Hoey, A.S. & Bellwood, D.R. 2008. Cross-shelf variation in the role of parrotfishes on the Great Barrier Reef. Coral Reefs 27: 37-47

Hutchins, B. 2004. Fishes of the Dampier Archipelago, Western Australia. Records of the Western Australian Museum, Supplement 66: 343–398 

Hutchins, J.B. 1994. A survey of the nearshore reef fish fauna of Western Australia's west and south coasts — The Leeuwin Province. Records of the Western Australian Museum, Supplement 46: 1-66 figs 1-6 

Hutchins, J.B. 1997. Checklist of fishes of the Houtman Abrolhos Islands, Western Australia. pp. 239-253 in Wells, F. (ed.) The Marine Fauna and Flora of the Houtman Abrolhos Islands, Western Australia. Perth : Western Australian Museum. 

Johnson, J.W. 2010. Fishes of the Moreton Bay Marine Park and adjacent continental shelf waters, Queensland, Australia. pp. 299-353 in Davie, P.J.F. & Phillips, J.A. Proceedings of the Thirteenth International Marine Biological Workshop, The Marine Fauna and Flora of Moreton Bay. Memoirs of the Queensland Museum 54(3) 

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

Larson, H.K., Williams, R.S. & Hammer, M.P. 2013. An annotated checklist of the fishes of the Northern Territory, Australia. Zootaxa 3696(1): 1-293

Nicholson, G.M. & Clements, K.D. 2020. Resolving resource partitioning in parrotfishes (Scarini) using microhistology of feeding substrata. Coral Reefs

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.

Russ, G. 1984. Distribution and abundance of herbivorous grazing fishes in the central Great Barrier Reef. I. Levels of variability across the entire continental shelf. Marine Ecology Progress Series 20: 23-34.

Smith, L.L., Fessler, J.L., Alfaro, M.E., Streelman, J.T. & Westneat, M.W. 2008. Phylogenetic relationships and the evolution of regulatory gene sequences in the parrotfishes. Molecular Phylogenetics and Evolution 49: 136-152. 

Welsh, J.Q. & Bellwood, D.R. 2012. Regional endothermy in a coral reef fish? PLoS ONE 7(3): e33187. doi:10.1371/journal.pone.0033187

Westneat, M.W. & Alfaro, M.E. 2005. Phylogenetic relationships and evolutionary history of the reef fish family Labridae. Molecular Phylogenetics and Evolution 36: 370–390.

Wainwright, P.C., D.R. Bellwood, D.R., M.W. Westneat, M.W., J.R. Grubich, J.R. & Hoey, A.S. 2004. A functional morphospace for the skull of labrid fishes: patterns of diversity in a complex biomechanical system. Biological Journal of the Linnean Society 82: 1-25

Quick Facts

CAAB Code:37386020


Conservation:IUCN Least Concern

Depth:1-50 m

Habitat:Reef associated

Max Size:80 cm TL

Species Maps

CAAB distribution map