2 from Argentina (15.2-17.3 mm PreA) FAKU AP 619, 641.
Description:
D 309; A 267; P1 9-10; LL pores 184.
ED 19.1% of PreA; BD 37.6, 41.4; SN 160.7; UJ 180.9; IO 6.9, 9.2; P1L 27.7, 34.9; PreD 52.6, 69.1; PreAn 92.5, 93.4.
Body extremely elongate and compressed throughout (less so anteriorly) with fine tapering tail. Elongate mouth formed with recurved needle-like jaws with swelled tips. Head small and slender, its length about 10 in TL. Upper jaw remarkably more projected forward than lower jaw. Posterior margin of upper jaw extending far beyond posterior margin of eye by about half of eye diameter. Saw-like minute teeth in several rows covering throughout both jaws. Vomer extending forward with upper jaw. Interorbital region narrow and flat, its length less than orbit. Gill-opening situated in fromt of pectoral fin base. Gill-membranes united to each other and to isthmus. Gill-slit just in front of pectoral fin base. No scales on body. Sensory pores well developed on lateral line, around orbital and interorbital regions and nape. Nostrils situated close each other in front of eye, anterior one large and tube-like, posterior one small and round without tube. Pectoral fin small, its end reaching to anus. Dorsal fin lower than anal fin, its origin above pectoral fin base. Dorsal and anal fins confluent with distinct rayed caudal at tip of tail. Caudal fin small not forked. Intermuscular bones well developed. Anus situated behind tip of pectoral fin by half length of pectoral fin.
Distribution:
Worldwide from 50°N to 50°S, in 50-4,600 m depth.
Remarks:
Position of anus is different between our specimens and Avocettina infans described by Hart (1973). It is far forward in the former than in the latter. Gloerfelt-Tarp and Kailola (1984) gave 14-18 pectoral fin rays of this species, and Ida (1982) gave 335 dorsal and 295 anal fin rays. There seems to be considerable local variations.
(Izumi NAKAMURA)
Distribution of Avocettina infans in Patagonia.
Lateral view of head. Head length (1) and preanal length(2).