本種の他にScomber属にはゴマサバScomber australasicusとScomber scombrusが認められている(Matsui, 1967; Collette and Nauen, 1983)。
(中村 泉)
Material examined:
10 from Chile (330.5-371.8 mm SL), FAKU CP 13, 394, 395, 401-404, 410, 411, 910.
Description:
D [-\, 10-12+5; A T, 10-12+5; P1 19-22; P2T, 5; GR 9-14+1+23-27=46-42.
HL 28.0-29.2% of SL; ED 5.0-5.7; BD 21.0-22.8; BW 14.4-18.0; SN 8.6-9.3; IO 5.8-6.1; UJ 9.9-10.4; CP 2.8-3.0; P1L 11.2-12.3; P2L 10.2-11.2; D1H 10.3-12.8; D2H 4.9-5.2; AH 4.0-4.8.
Body fusiform, slightly compressed. Head large, 3.4-3.7 in SL. Mouth large, terminal, end of upper jaw reaching anterior margin of eye. Maxilla completely covered with rachrymal, when mouth closed. Eye large, about 5.5 times in head. Adipose eyelid well developed. Fine villiform teeth on jaws, vomer and palatines. Snout bluntly pointed. Long, slender gill-rakers with fine inner bristles on first gill-arch. Two nostrils, anterior nostril small, round, posterior nostril small, slit-like. Olfactory rosetta radial type. Pseudobranchiae well developed. Interorbital region wide, almost flat or evenly arched. Small cycloid scales on body. Head naked except opercle. Pectoral fin short, slightly longer than pelvic fin. First dorsal fin high, triangular and well separated from second dorsal fin, followed by 5 or 6 finlets. A detached anal fin spine just in front of anal fin, 10 to 12 soft rays followed by 5 or 6 finlets. Caudal fin deeply forked, with two subparallel scaly ridge (caudal keels) at its base on either side. First dorsal, pectoral and pelvic fins recessed when depressed. Lateral line slightly undulated and gradually descending anteriorly and fairly straight posteriorly. Metallic blue dorsally, silvery ventrally. Wavy irregular black stripes present on dorsal part.
Distribution:
Worldwide, though many local populations are recognized.
Remarks:
Recent review recognized 3 species in Scomber, S. japonicus, S. australasicus and S. scombrus (Matsui, 1967; Collette and Nauen, 1983).
(Izumi NAKAMURA)
Distribution of Scomber japonicus in Patagonia.
Olfactory rosetta (above). Tail in lateral view (below). Caudal keels (1), dorsal finlets (2) and anal finlets (3).