Thicklip Wrasse, Hemigymnus melapterus (Bloch 1791)

Other Names: Blackedge Thicklip Wrasse, Blackeye Thicklip, Blackeye Thicklip Wrasse, Black-eyed Thicklip, Black-eyed Thick-lip, Half & Half Wrasse, Half-and-half Thicklip, Half-and-half Wrasse, Half-half Thicklip, Thicklip Wrasse, Thicklipped Wrasse, Thick-lipped Wrasse

A male (Terminal phase) Thicklip Wrasse, Hemigymnus melapterus, at Palau. Source: Mark Rosenstein / iNaturalist. License: CC by Attribution-NonCommercial-ShareAlike


Often seen taking in mouthfuls of sand to sift out invertebrates before passing the sand out through the gill openings.

Adults are mostly whitish to pale greenish or greyish anterior to a diagonal line between the dorsal and anal fin origins, blackish to dark green posteriorly, with a pattern of scribbles and lines on the head. Juveniles are greenish-brown with a diagonal white bar behind the pectoral fin.

Cite this page as:
Dianne J. Bray, Hemigymnus melapterus in Fishes of Australia, accessed 22 Jun 2024,

Thicklip Wrasse, Hemigymnus melapterus (Bloch 1791)

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Recorded in tropical and subtropical waters in Australia from the Houtman Abrolhos (Western Australia) to Sydney (New South Wales); also at Christmas and Cocos Keeling islands, Lord Howe Island and Elizabeth and Middleton Reefs, in depths of 1-40 m.

Elsewhere, widespread in the Indo-Pacific, from the Red Sea and East Africa to French Polynesia and Pohnpei.

Common on shallow coral reefs throughout its range - on subtidal reef flats, lagoons, outer reef slopes and drop-offs. The Thicklip Wrasse is often seen on sandy and rubble areas around reefs and bommies.


Changes colour dramatically from juvenile to adult. Juveniles are greenish-brown with a diagonal white bar behind the pectoral fin, before developing the pale anterior and dark posterior bicolor pattern.


Juveniles feed on tiny planktonic crustaceans near the bottom. Adults feed by taking in mouthfuls of sand to sort out the invertebrates (crustaceans, molluscs, brittle stars). The sand is then expelled through the gill openings.


Taken in multispecies fisheries and collected for the aquarium trade.


Dianne J. Bray

Thicklip Wrasse, Hemigymnus melapterus (Bloch 1791)


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

Allen, G.R. & Smith-Vaniz, W.F. 1994. Fishes of Cocos (Keeling) Islands. Atoll Research Bulletin 412: 1-21

Allen, G.R. & Steene, R.C. 1988. Fishes of Christmas Island, Indian Ocean. Australian government Publishing Service, Canberra, Australia, 197 pp.

Allen, G.R. & Swainston, R. 1988. The Marine Fishes of North-Western Australia. A field guide for anglers and divers. Perth, WA : Western Australian Museum vi 201 pp., 70 pls.

Allen, G.R., N.J. Cross, C.J. Allen & M.F. Gomon 2006. Labridae: Labrinae. pp. 1368-1418 in Beesley, P.L. & Wells, A. (eds). Zoological Catalogue of Australia. Volume 35 Australia : ABRS & CSIRO Publishing Parts 1-3, 2178 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.

Alleyne, H.G. & Macleay, W.J. 1877. The ichthyology of the Chevert Expedition. Proceedings of the Linnean Society of New South Wales 1(3–4): 261-281, 321-359, pls 3-9, 10-17 [pp. 261-281, pls 3-9 published Feb 1877; pp. 321-359, pls 10-17 published Mar 1877]

Bloch, M.E. 1791. Naturgeschichte der ausländischen Fische. Berlin : J. Morino Vol. 5 152 pp. pls 253-288.

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.

Eckert, G. 1987. Estimates of adults and juvenile mortality for labrid fishes at One Tree Island, Great Barrier Reef. Marine Biology 95: 167-171.

Francis, M. 1993. Checklist of the coastal fishes of Lord Howe, Norfolk, and Kermadec Islands, southwest Pacific Ocean. Pacific Science 47(2): 136-170 figs 1-2

Grant, E.M. 1975. Guide to Fishes. Brisbane : Queensland Government, Co-ordinator General’s Department 640 pp.

Grant, E.M. 1991. Fishes of Australia. Brisbane : EM Grant Pty Ltd 480 pp.

Grutter, A. 1998. Habitat-related differences in the abundance of parasites from a coral reef fish : an indication of the movement patterns of Hemigymnus melapterus. Journal of Fish Biology 53: 49-57.

Grutter, A.S., Deveney, M.R., Whittington, I.D. & Lester, R.J.G. 2002. The effect of the cleaner fish Labroides dimidiatus on the capsalid monogean Benedenia lolo parasite of the labrid fish Hemmigymnus melapterus. Journal of Fish Biology  61(5): 1098-1108.

Henry, G.W. & Lyle, J.M. 2003. The National Recreational and Indigenous Fishing Survey. NSW Fisheries Final Report Series: 48. Fisheries Reserach & Development Corporation and the Fisheries Action Program, Canberra, Australia.

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

Hutchins, J.B. 2001. Checklist of the fishes of Western Australia. Records of the Western Australian Museum, Supplement 63: 9-50

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. 1997. Guide to sea fishes of Australia. A comprehensive reference for divers and fishermen. Frenchs Forest, NSW, Australia : New Holland Publishers I-xvii, 434 pp.

Kuiter, R.H. 2002. Fairy and rainbow wrasses and their relatives - a comprehensive guide to selected labrids. TMC Publishing, Chorleywood, UK.

Oxley, W.G., Ayling, A.M., Cheal, A.J. & Osborne, K. 2004. Marine surveys undertaken in the Elizabeth and Middleton Reefs Marine National Nature Reserve, December 2003. Townsville : Australian Institute of Marine Sciences 64 pp.

Parenti, P. & Randall, J.E. 2000. An annotated checklist of the species of the labroid fish families Labridae and Scaridae. Ichthyological Bulletin of the J.L.B. Smith Institute, Grahamstown 68: 1-97

Randall, J.E. 1986. Family No. 220: Labridae. pp. 683-706 in Smith, M.M. & Heemstra, P.C. (eds). Smith's Sea Fishes. Johannesburg : Macmillan South Africa xx + 1047 pp. 144 pls.

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.

Shea, S., Liu, M., Sadovy, Y., Craig, M.T. & Rocha, L.A. 2010. Hemigymnus melapterus. In: IUCN 2012. IUCN Red List of Threatened Species. Version 2012.2. <>. Downloaded on 15 December 2012.

Victor, B.C. 1986. Duration of the planktonic larval stage of one humdred species of Pacific and Atlantic wrasses  (family Labridae). Marine Biology 90(3): 317-326.

Westneat, M.W. 2001. Labridae. pp. 3381-3467 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.

Quick Facts

CAAB Code:37384125

Biology:Hermaphrodite - changes sex

Conservation:IUCN Least Concern

Depth:1-40 m

Habitat:Reef associated

Max Size:45 cm TL

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