Blackspotted Croaker, Protonibea diacanthus (Lacépède 1802)

Other Names: Black Croaker, Black Jew, Black Jewfish, Black Spotted Croaker, Black-spotted Croaker, Blotched Jewfish, Jewy, Mulloway, Spotted Croaker, Spotted Jewfish, Two-spined Jewfish

Blackspotted Croaker, Protonibea diacanthus. Source: Australian National Fish Collection, CSIRO. License: CC by Attribution-NonCommercial-ShareAlike

Black jewfish can be distinguished from southern jewfish (mulloway) by the narrower shape of the tail peduncle, and their darker colouration. This species has a rapid growth rate, reaching 60 cm in around 2 years and maturing in around 4 years at 80-90 cm.    Fish Distribution: This species occurs throughout the Indo-west Pacific region from the Persian Gulf and India, north to Japan and south to Papua New Guinea and northern Australia. They occur in estuaries and coastal waters over muddy bottoms, rocky reefs and other structures.  There are several different populations of black jewfish in northern Australia, each with its own discreet spawning area to which fish return year after year.

Cite this page as:
Bray, D.J. 2022, Protonibea diacanthus in Fishes of Australia, accessed 21 Jun 2024,

Blackspotted Croaker, Protonibea diacanthus (Lacépède 1802)

More Info


South of Onslow, Western Australia, to north of Mackay, Queensland. Elsewhere the species occurs in the tropical, Indo-west Pacific. Inhabit estuarine and coastal waters over muddy bottoms and offshore to depths of 100 m. 


Opportunistic feeders, preying mostly on crustaceans and small fishes.


Forms spawning aggregations.


A popular recreational and commercial species. Individuals caught below 10 m are susceptible to barotrauma-induced injuries (tissue damage due to expansion of the swim bladder on ascent). As a result, catch and release from water deeper than 15 m is not recommended.

Species Citation

Lutjanus diacanthus Lacépède 1802, Hist. Nat. Poiss. 4 : 240. Type locality unknown.


Bray, D.J. 2022

Blackspotted Croaker, Protonibea diacanthus (Lacépède 1802)


Allan, R. 2002. Australian Fish and How to Catch Them. Sydney : New Holland Publishers (Australia) 394 pp. (as Johnius diacanthus)

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

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. 

Gloerfelt-Tarp, T. & Kailola, P.J. 1984. Trawled Fishes of Southern Indonesia and Northwest Australia. Jakarta : Dir. Gen. Fish. (Indonesia), German Tech. Coop., Aust. Dev. Ass. Bur. 406 pp. 

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

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

Lacépède, B.G. 1802. Histoire Naturelle des Poissons. Paris : chez Plassan Vol. 4 728 pp. 16 pls.   

Larson, H.K. & Williams, R.S. 1997. Darwin Harbour fishes: a survey and annotated checklist. pp. 339-380 in Hanley, H.R., Caswell, G., Megirian, D. & Larson, H.K. (eds) The Marine Flora and Fauna of Darwin Harbour, Northern Territory, Australia. Proceedings of the Sixth International Marine Biology Workshop. Darwin : Museum and Art Gallery of the Northern Territory 466 pp.  Sainsbury, K.J., Kailola, P.J. & Leyland, G.G. 1984. Continental Shelf Fishes of Northern and North-Western Australia. Canberra : Fisheries Information Service 375 pp. figs & pls.   

Sasaki, K. 1996. Sciaenid fishes of the Indian Ocean (Teleostei, Perciformes). Memoirs of the Faculty of Science. Kôchi University D Biol. 16/17: 83-95.   

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Trewavas, E. 1977. The sciaenid fishes (croakers or drums) of the Indo-West Pacific. Transactions of the Zoological Society of London 33: 253-541 figs 1-61 pls 1-14  

Whitley, G.P. 1945. New sharks and fishes from Western Australia. Part 2. The Australian Zoologist 11(1): 1-42 figs 1-15. (as Sciaena antarctica rex)  

Yearsley, G.K., Last, P.R. & Ward, R.D. (eds) 1999. Australian Seafood Handbook. Hobart : CSIRO Marine Research 460 pp.

Quick Facts

CAAB Code:37354003

Depth:to 100 m

Fishing:Recreational, commercial fish

Habitat:Estuarine, coastal waters over muddy bottoms

Max Size:150 cm SL

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Species Maps

CAAB distribution map