Midget Flathead, Onigocia spinosa (Temminck & Schlegel 1843)

Other Names: Largescaled Spiny Flathead, Spiny Flathead

A Midget Flathead, Onigocia spinosa, at Coogee Beach, Western Australia, March 2018. Source: Glen Whisson / iNaturalist.org. License: CC By Attribution-NonCommercial

A small mottled grey to reddish flathead with about 3-4 darker bands across the back and sides, the most prominent between the first and second dorsal fins, a band behind the second dorsal fin and another at the caudal-fin base. The pelvic fins are dark brown with a pale margin. 

Video of Midget Flatheads (aka Spiny Flathead) in Lembeh Strait, North Sulawesi, Indonesia

Cite this page as:
Australian National Fish Collection, CSIRO & Bray, D.J. 2020, Onigocia spinosa in Fishes of Australia, accessed 15 Jul 2024, https://fishesofaustralia.net.au/home/species/4427

Midget Flathead, Onigocia spinosa (Temminck & Schlegel 1843)

More Info


Rockingham, Western Australia, around the tropical north to off Swains Reefs, Queensland, including the Ashmore Reef area in the Timor Sea. Elsewhere the species occurs on the continental shelf and upper slope in Indonesia, the Philippines, and north to southern Japan. Although taken as bycatch in commercial trawls, the species also inhabits shallow muddy, sandy and rubble areas near reefs.

The Midget Flathead is nocturnal and usually buries itself in the substrate during the day.


Dorsal fin IX or I,VIII, 11-12 (usually 12); Anal fin11-12; Pectoral fin 20-23 (usually 21 or 22); Lateral line scales (pored) 34-42 (usually 37 or 38).

Body elongate. Head large (length 37-42% SL), moderately depressed, with several low, mostly spined, ridges; eyes large (~27-30% HL) with ocular flap; 3-6 preocular spines; mouth with small, sharp teeth; three preopercular spines at angle of preopercle, uppermost longest; interopercular flap absent; total gill rakers on first gill arch 5-6 (usually 5). Scales finely ctenoid dorsally, cycloid ventrally, covering body and most of head behind eyes, not deciduous; oblique scale rows slanting backward above lateral line are about equal to the number of lateral-line scales; 34-42 (usually 37 or 38), anterior 8-15 scales bearing spines. Scale pores of lateral line with 2 openings to the exterior. First dorsal fin spinous with short base, first spine short, following spines much longer. Second dorsal fin with moderately long base, anterior rays longest, nearly as long as longest first dorsal spines. Anal fin similar in shape, and opposite and slightly longer-based than second dorsal fin. Caudal fin truncate to slightly rounded. Pectoral fins moderately small. Pelvic fins long, based below centre of pectoral fins, reaching to about anal fin origin.


Head and body tan or brown above, pale below; back crossed by about 3-4 darker bands. Anal fin pale, with a faint submarginal band; anterior half of spinous dorsal fin with brown spots on spines, posterior half of fin brown with yellow flecks, may have dusky blotches forming about 3 horizontal bands; soft dorsal fin with series of brown spots forming horizontal bands; pectoral fins with dark spots forming vertical bands; pelvic fins mostly dark, light distally.


May be taken as incidental bycatch in commercial trawl fisheries.


IUCN Least Concern

Species Citation

Platycephalus spinosus Temminck & Schlegel 1843, Fauna Japonica 1843(2-4): 40, pl. 16(1, 2). Type locality: Nagasaki, Japan.


Australian National Fish Collection, CSIRO & Bray, D.J. 2020


Atlas of Living Australia

Midget Flathead, Onigocia spinosa (Temminck & Schlegel 1843)


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. & 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. H

Hutchins, J.B. 2003. Checklist of marine fishes of the Dampier Archipelago, Western Australia. pp. 453-478 in Wells, F.E., Walker, D.I., & Jones, D.S. (eds). Proceedings of the Eleventh International Marine Biological Workshop: The Marine Flora and Fauna of Dampier, Western Australia. Perth : Western Australian Museum. 

Imamura, H. 1996. Phylogeny of the family Platycephalidae and related taxa (Pisces: Scorpaeniformes). Species Diversity 1(2): 123-233 

Imamura, H. 2011. Onigocia sibogae, a replacement name for a distinct species of flathead fish, Platycephalus grandisquamis Weber, 1913 (Teleostei: Platycephalidae). Zootaxa 3066: 52-60 

Imamura, H. & Knapp, L.W. 2009. A new species of the flathead genus Onigocia (Teleostei: Platycephalidae) collected from the Coral and Tasman seas. Zootaxa 2008: 23-38 

Imamura, H. & McGrouther, M.A. 2008. New records of a flathead fish, Onigocia grandisquama (Regan, 1908) (Teleostei: Platycephalidae) from Australia. Memoirs of the Queensland Museum 52(2): 239-243

Jordan, D.S. & Thompson, W.F. 1913. Notes on a collection of fishes from the island of Shikoku in Japan, with a description of a new species, Gnathypops iyonis. Proceedings of the United States National Museum 46(2011): 65-72 figs 1-5 

Keenan, C.P. 1991. Phylogeny of Australian species of flatheads (Teleostei, Platycephalidae) as determined by allozyme electrophoresis. Journal of Fish Biology 39(Supplement A): 237-249 

Knapp, L.W. 1999. Family Platycepalidae. pp. 2385-2421 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. 4 pp. 2069-2790. 

Knapp, L.W., Imamura, H. & Sakashita, M. 2000. Onigocia bimaculata, a new species of flathead fish (Scorpaeniformes: Platycephalidae) from the Indo-Pacific. Special Publication J.L.B. Smith Institute of Ichthyology 64: 1-10 

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. 

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

Motomura, H. & Matsuura, K. 2016. Onigocia spinosa. The IUCN Red List of Threatened Species 2016: e.T69789961A69800862. http://dx.doi.org/10.2305/IUCN.UK.2016-3.RLTS.T69789961A69800862.en. Downloaded on 18 September 2019.

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. 

Temminck, C.J. & Schlegel, H. 1843. Pisces. 21-72 pls 7A-36 in Siebold, P. Fr de (ed.) Fauna Japonica. Leyden : Apud Arnz & Socios Vol. 4(2–4).

Quick Facts

CAAB Code:37296022

Biology:Venomous spines

Conservation:IUCN Least Concern

Depth:8-250 m

Habitat:Reef associated, silt/sand/rubble areas

Max Size:25 cm TL

Species Image Gallery

Species Maps

CAAB distribution map