Slender Cardinalfish, Rhabdamia gracilis (Bleeker 1856)

Other Names: Luminous Cardinalfish, Slender Cardinal, Slender Cardinal-fish

Slender Cardinalfish, Rhabdamia gracilis, at North West Solitary Island, New South Wales, 19 June 2015, depth 11 m. Source: Ian Shaw / iNaturalist. License: CC by Attribution-NonCommercial

An almost transparent cardinalfish with a silvery head and abdomen, a black tip on one or both caudal-fin lobes, a bluish mid-lateral stripe, and a reddish patch on the gill cover behind the eye. Females larger than 4 cm SL have one or two dark stripes along the sides, which are absent in males and smaller females.

Cite this page as:
Bray, D.J. 2022, Rhabdamia gracilis in Fishes of Australia, accessed 02 Mar 2024,

Slender Cardinalfish, Rhabdamia gracilis (Bleeker 1856)

More Info


Houtman Abrolhos Islands, and offshore reefs of north Western Australia, and Ashmore and Cartier Islands in the Timor Sea, to Sydney, New South Wales; also Cocos (Keeling) Islands in the eastern Indian Ocean. Elsewhere the species occurs in the tropical, Indo-west-central Pacific, from East Africa to the Marshall Islands, and north to Japan. Forms large dense schools in gutters and above the reef.


Dorsal fin VII, 9; Anal fin 12-13. 
Greatest depth of body 3.3-3.6 in SL.


Translucent whitish to pinkish, head and abdomen silvery; bluish midlateral stripe; posteriorly placed black spot; sometimes on caudal peduncle; one or both caudal-fin lobes with black tip.


Feeds on plankton above the reef during the day and at night.


Slender Cardinalfish are used as bait in commercial fisheries such as Skipjack Pole-and-line fisheries.

Species Citation

Apogonichthys gracilis Bleeker 1856, Natuurkundig Tijdschrift voor Nederlandsch Indië 10: 371. Type locality: Ternate, Moluccas, Indonesia.


Bray, D.J. 2022


Atlas of Living Australia

Slender Cardinalfish, Rhabdamia gracilis (Bleeker 1856)


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

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. 

Blaber, S.J.M., Brewer, D.T. & Harris, A.N. 1994. Distribution, biomass and community structure of demersal fishes of the Gulf of Carpentaria, Australia. Australian Journal of Marine and Freshwater Research 45(3): 375-396.

Bleeker, P. 1856. Zevende bijdrage tot de kennis der ichthyologische fauna van Ternate. Natuurkundig Tijdschrift voor Nederlandsch Indië 10: 357-386 

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., Williams, D.McB., Newman, S.J., Cappo, M. & Speare, P. 1995. New records of fishes for the Rowley Shoals and Scott/Seringapatam Reefs, off north-western Australia. Records of the Western Australian Museum 17: 119-123 

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. 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. & Kozawa, T. 2019. Cardinalfishes of the world. New edition. Seaford, Victoria : Aquatic Photographics and Okazaki, Aichi, Japan: Anthias, Nexus: 1-198.

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 

Mabuchi, K., Fraser, T.H., Song, H., Azuma, Y. & Nishida, M. 2014. Revision of the systematics of the cardinalfishes (Percomorpha: Apogonidae) based on molecular analyses and comparative reevaluation of morphological characters. Zootaxa 3846(2): 151–203 

Randall, J.E. 2005. Reef and shore fishes of the South Pacific. New Caledonia to Tahiti and the Pitcairn Islands. Honolulu : University of Hawaii Press 707 pp. 

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. & Houston, W. 1989. Offshore fishes of the Arafura Sea. The Beagle 6(1): 69-84.

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.

Siddique, M.A.M., Arshad, A. & Amin, S.N.M. 2015. Length‐weight and length‐length relationships of two tropical fish Secutor megalolepis (Mochizuki & Hayashi, 1989) and Rhabdamia gracilis (Bleeker, 1856) from Sabah, Malaysia. Journal of Applied Ichthyology 31(3): 574-575

Yoshida, T., Mabuchi, K. & Motomura, H. 2018. Rhabdamia novaluna, a new species of cardinalfish (Perciformes: Apogonidae) from the western Pacific Ocean, with comments on the synonymy of Rhabdamia gracilisIchthyological Research 66(1): 129-139.

Yoshida, T. & Motomura, H. 2018. Redescription of the Indo-West Pacific cardinalfishes (Perciformes: Apogonidae) Rhabdamia spilota Allen & Kuiter 1994 and R. gracilis (Bleeker 1856). Zootaxa 4377(2): 178-190

Quick Facts

CAAB Code:37327022


Depth:1-90 m

Habitat:Reef associated

Max Size:6 cm TL

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Species Maps

CAAB distribution map