Breaksea Cod, Epinephelides armatus (Castelnau 1875)

Other Names: Black-arse, Black-arse Cod, Black-arsed Cod, Break-sea Cod, Breaksea Rock Cod, Tiger Cod

A Breaksea Cod, Epinephelides armatus, at Albany, Western Australia. Source: Rick Stuart-Smith / Reef Life Survey. License: CC by Attribution

A relatively large cod found only in Western Australia. The Breaksea Cod has a large 'square' tail and is highly variable in colour, ranging from yellow, pink or greenish, to brown or grey, with a distinctive black blotch around the anus (hence one of the other names - Black-arse Cod).

Unlike many other cods or groupers, this species does not change sex during its life.

Cite this page as:
Dianne J. Bray, Epinephelides armatus in Fishes of Australia, accessed 18 Jul 2024,

Breaksea Cod, Epinephelides armatus (Castelnau 1875)

More Info


Endemic to Western Australia, from the Recherche Archipelago in the south, to Shark Bay on the west coast. Inhabits offshore limestone and coral reefs to depths of 100 m, commonly to about 35 m.


Meristic features: Dorsal fin X, 20; Anal fin III, 7–8; Caudal fin 17; Pectoral fin 15; Pelvic fin I, 5; lateral line scales  ~about 70.
Body depth 37–40% SL; head length ~ about 33% SL; eye diameter 16–22% HL.


Grows to a maximum length of 56 cm TL, and a  weight of 3 kg; commonly 30-40 cm.


Pinkish grey to black, paler below; each scale with pale centre; anus black; fins grey to black with paler margins. Adults with a yellowish or greenish shine. Juveniles are paler than the adults and have the front of the head dark.


Carnivore - an ambush predator that feeds mostly on fishes.


Unlike many serranid species, the Breaksea Cod is a gonochrist - meaning that the sexes are separate and individuals do not change sex.
Moore et al. (2007) found that the spawning period lasts for about 9 months, and that females grow more slowly and take longer to mature that males. 
Like many other groupers, the Breaksea Cod is long-lived and matures slowly (3–4 years) making it vulnerable to overexploitation. Individuals mature at 3-4 years of age at lengths of around 23-27 cm (females) and 27-35 cm (males). Maximum age is about 20 years.


An important recreational species in southwestern Australia, and taken on hook and line; also occasionally taken in commercial trawls.


IUCN Red List of Threatened Species: Near Threatened

Species Citation

Serranus armatus Castelnau, 1875, Intercolonial Exhibition Essays 2: 7. Type locality: Swan River, Western Australia.


Dianne J. Bray

Breaksea Cod, Epinephelides armatus (Castelnau 1875)


Castelnau, F.L. de 1875. Researches on the fishes of Australia. Intercolonial Exhibition Essays. 2. pp. 1–52 in, Philadelphia Centennial Exhibition of 1876 : Official Record. Melbourne.

Coleman, N. 1980. Australian Sea Fishes South of 30ºS. Lane Cove, NSW : Doubleday Australia Pty Ltd 309 pp.
Cornish, A. (Grouper & Wrasse Specialist Group) 2004. Epinephelides armatus. In: IUCN 2013. IUCN Red List of Threatened Species. Version 2013.2. . Downloaded on 28 December 2013.

Eastman A. 2001. Age, growth and reproductive biology of the Breaksea Cod Epinephelides armatus. Honours thesis, Curtin University of Technology, Australia 67pp.

Grant, E.M. 2002. Guide to Fishes. Redcliffe : EM Grant Pty Ltd 880 pp.

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. 1994. Families Serranidae, Callanthiidae. pp. 528-548 figs 469-485 in Gomon, M.F., Glover, C.J.M. & Kuiter, R.H. (eds). The Fishes of Australia's South Coast. Adelaide : State Printer 992 pp. 810 figs.

Kuiter, R.H. 1996. Guide to Sea Fishes of Australia. A comprehensive reference for divers and fishermen. Sydney, NSW, Australia : New Holland Publishers xvii, 434 pp.

Kuiter, R.H. 2004. Basslets, Hamlets and their relatives. A comprehensive guide to selected Serranidae and Plesiopidae. Chorleywood, UK : TMC Publishing 1, 216 pp.

Moore, S.E., Hesp, S.A., Hall, N.G. & Potter, I.C. 2007. Age and size compositions, growth and reproductive biology of the breaksea cod Epinephelides armatus, a gonochoristic serranid. Journal of Fish Biology 71(5): 1407-1429.

Prokop, F. 2002. Australian Fish Guide. Australian Fishing Network, Victoria, Australia. 224pp.

Roberts, C.D. & Gomon, M.F. 2008. Families Polyprionidae, Serranidae and Callanthiidae. pp. 534-549 in Gomon. M.F., Bray, D.J. & Kuiter, R.H (eds). Fishes of Australia's Southern Coast. Sydney : Reed New Holland 928 pp.

Quick Facts

CAAB Code:37311100

Conservation:IUCN Near Threatened

Depth:0-100 m

Fishing:Recreational fish

Habitat:Reef associated

Max Size:56 cm TL


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CAAB distribution map