アルゼンチンの南緯38度から46度にかけてのサン マティアス湾を含む沿岸域から陸棚上の水深180m付近にかけて採集された。本種は通常,リオデジャネイロからウルガイ沖の水深60〜200mにかけて分布する(Figueiredo and Menezes, 1978)。
備 考:
本種は体に不規則な縞紋様がないこと及び体型の違いで近縁のG. blacodesと異なる。
(稲田伊史)
Material examined:
7 from Argentina (318-688 mm SL), FSFL EM 29, 164, 165, 174, 235, 357, 413.
Description:
D 132-137; A 101-109; P1 22-25; P2 2; C 8-9; GR 1+3-5 (lower); LLS 46-54 (pores); BR 7; X 18+48=66.
HL 21.5-23.7 % of SL; BD 11.7-16.2; PreD 27.1-31.4; PreA 44.2-47.7; End of LL to end of urostyle 7.4-9.5; ED 14.4-16.9 % of HL; SN 23.6-25.4; IO 16.7-20.9; UJ 44.2-46.8; P1L 35.0-40.0; P2L 37.9-43.4; DH 11.2-13.9; AH 10.2-13.8.
Body elongate, tapering and cylindrical in cross section. Head slightly depressed; snout bluntly pointed; eye small. Mouth large; posterior end of upper jaw well posterior to posterior margin of eye; teeth on symphysis of upper jaw canine-like; teeth on jaws, palatine and vomer conical. A large spine concealed by skin on opercle. Pectoral fin short, its tip rounded; pelvic fin with two slender barbel-like rays situated well anteriorly on lower jaw; inner ray longer than outer. Dorsal fin origin situated slightly backward of pectoral fin origin; anal fin origin slightly anterior to midpoint of body. Dorsal and anal fins continuous to caudal fin. Gill-rakers on upper arches knob-like and those on lower arches short and tough. Lateral line wavy, ending beneath about 110th ray of dorsal fin, with irregularly positioned small pores.
Distribution:
On continental shelf of northern Argentina, including the San Matias Bay in depths less than 180 m. This species probably prefers to live in warmer, coastal waters than Genypterus blacodes.
Remarks:
This species is distinguished from G. blacodes by the following characters: 1) Absence of bloches or mottles in body colour, 2) More pointed tip of snout. 3) Lower jaw included in upper jaw when mouth closed, with several anterior upper teeth exposed.
(Tadashi INADA)
Distribution of Genypterus brasiliensis in Patagonia.