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Rusty Flathead Inegocia japonica (Tilesius, 1812)
[CAAB 37 296029]

Distribution Map see an interactive map here (new window)

Distribution, ecology and habitat:

Continental shelf of northern Australia from Moreton Bay, Queensland to Cockburn Sound, Western Australia. Widespread internationally, including Papua New Guinea, Indonesia, Philippines, southern Japan, South China Sea, Gulf of Thailand to India and Sri Lanka. Demersal in bays and coastal waters to depths of about 85 m.

Size:

Maximum total length about 25 cm, commonly to 20 cm TL.

Food and feeding:

Reproduction and early life history:

Characteristics:

D. IX or I,VIII: 11–13 (usually 12). A. 11–13 (usually 12). P. 19–21 (usually 19 or 20). V. I, 5. LL. (pored) 51–55 (usually 52 or 53).

Body elongate, moderately depressed. Head large (length ~34–35% SL), moderately depressed, supraorbital ridge smooth anteriorly, with serrations over posterior half of eye; preorbital spine absent; a single preocular spine; suborbital ridge usually smooth except for 2 spines under eye (specimens from Indonesia and Australia frequently have a few additional small serrations); Lower side of head bicarinate; ocular flap absent; teeth on jaws low and fine, teeth on vomer in two parallel longitudinal patches; preopercular spines usually 3, upper preopercular spine short, subequal with next; small accessory spine usually present; interopercular flap elongate, pointed; Total gill rakers on first arch 5–7 (usually 6). Scales small, finely ctenoid dorsally, cycloid ventrally, covering body and most of head behind eyes; Oblique scale rows slanting downward above lateral line closely approximate number of lateral-line scales. Lateral-line scales 51–55 (usually 52 or 53), anterior 2–21 scales bearing a small spine or ridge. First dorsal fin spinous, base length moderate, first spine very short, connected by a low membrane to second, following spines much longer. Second dorsal fin base longer than first, anterior rays longest, nearly as long as longest first dorsal spines. Anal fin similar in shape, opposite and slightly longer-based than second dorsal fin. Caudal fin rounded.

Colour:

Head and body orange-brown or grey above, whitish below, about 6 obscure dark bands across back. Caudal fin pale with about 3 series of black spots over entire fin, becoming larger and more elongated ventrally; pectoral and pelvic fins with large brown spots, sometimes forming weak bands.

Similar species:

Fisheries:

Taken by trawls over sand and mud bottom.

Conservation Status:

Remarks:

Other common names:

Japanese Flathead.

Original citation:

Platycephalus japonicus Tilesius, 1812, Krusenstern's Atlas, Nagasaki, Japan, no types known.

Etymology:

References:

Eschmeyer, W.N. (2008) The Catalogue of Fishes on-line. (California Academy of Sciences: San Francisco) Available from: http://www.calacademy.org/research/ichthyology/catalog/fishcatmain.asp (10 March, 2008).

Hoese, D.F., Bray, D.J., Paxton, J.R. & Allen, G.R. (2006) Fishes. In: P.L. Beesley & A. Wells (eds) Zoological Catalogue of Australia Volume 35. Parts 1-3. Australian Biological Resources Study and CSIRO Publishing, 2248 pp.

Knapp, L.W. (1999) Family Platycephalidae, flatheads, pp. 2385-2421. In: K.E. Carpenter & V.H. Niem (eds). FAO Species Identification Guide for Fishery Purposes. The Living Marine Resources of the Western Central Pacific. Volume 4: Bony Fishes Part 2 (Mugilidae to Carangidae). Food and Agriculture Organization of the United Nations, Rome.

Sainsbury, K.J., Kailola, P.J. & Leyland, G.C. (1985) Continental Shelf Fishes of Northern and North-Western Australia. Canberra, C.S.I.R.O. Division of Fisheries Research, 375 pp.