Systematics and distribution of leptocephali in the western South Atlantic

Leptocephali collected from the western South Atlantic between 33°–48°S and 47°–63°W during 1966–1998 were examined and described. Six families and twelve species were recorded (Congridae: Ariosoma opistophthalmum (Ranzani, 1840), Bassanago albescens (Barnard, 1923), Bathycongrus dubius (Breder, 1927), Conger orbignyanus Valenciennes, 1847, Gnathophis mystax (De La Roche, 1809); Chlopsidae: Chlopsis bicolor Rafinesque, 1810; Muraenidae: Gymnothorax conspersus Poey, 1867; "Unidentified leptocephali Type I, species A"; Ophichthidae: Ophichthus gomesii (Castelnau, 1855), Myrophinae: unidentified leptocephalus; Nettastomatidae: Hoplunnis tenuis Ginsburg, 1951, Saurenchelys stylura (Lea, 1913). Where no previous species descriptions were available, larval distributions and morphological data of adults are provided and discussed.