D 82; A 65; P1L 10; P2 T, 5; GR 1+10=11; BR 7; LLS 78.
HL 28.5% of SL; ED 2.7; BO 5.2; BD 49.8; SN 5.7; FO 1.4; BO 5.7; UJ 14.3; CP 11.1; P1L 16.5; P2L 7.5; DH 11.3; AH 11.2.
Body elliptical and extremely depressed, body depth about 2 times in SL. Head large, about 3.6 times in SL. Snout short, about equal to fleshy orbit. Upper profile of head anterior to upper eye slightly concave. Eye large, lower eye slightly anterior to upper eye, fleshy orbit 4.5 times in head. Mouth curved and oblique, posterior margin of upper jaw reaching lower eye. Upper jaw slightly anterior to lower jaw. Sharp fine conical teeth uniserial on both jaws, teeth on lower jaw larger and more sparsely arranged than teeth on upper jaw. No teeth on vomer or palatines. Gill-rakers short and stout with fine inner serrations. Pseudobranchiae present. Nostrils on ocular side situated close each other, anterior to eye, naerer to eye than to tip of snout, anterior nostril round with a flap and posterior nostril round without a flap and larger than anterior nostril. Nostrils on blind side situated closely each other and near to dorsal profile of head, similar to nostrils on ocular side. Interorbital region very narrow with a bony ridge. Dorsal fin originating from blind side, just above posterior nostril. Pectoral fin long, slender, its length about 1.7 times in head on ocular side and 2.5 on blind side. Pelvic fins slightly longer on blind side than on ocular side. Caudal fin double truncate. Scales on both blind and ocular sides ctenoid. Lateral line with a branch and a curving anteriorly and fairly straight posteriorly.
Distribution:
Coasts of Brazil to Argentina.
Remarks:
This species may prove to be identical with P. triocellatus Ribeiro, 1904 over which P. isoseles has priority (Norman, 1934).
(Izumi NAKAMURA)
Distribution of Paralichthys isosceles in Patagonia.