Early development of the manefishes Caristius macropus and Paracaristius nudarcus (Caristiidae), based on aquarium-reared specimens.

Abstract

Fertilized eggs of two manefishes (Caristius macropus and Paracaristius nudarcus) were collected off Shionomisaki, Wakayama Prefecture, Japan and hatched in an aquarium. Descriptions are provided for early-life stages of both species [C. macropus (6 specimens: 8.9–125.9 mm in standard length: SL; maximum rearing period 255 days) and P. nudarcus (26.8 mm SL; 64 days)], based on the reared larval and juvenile specimens. Characters known to be diagnostic for the genus Caristius, including small sized lateralline scales and serrated lower caudal-fin rays, appeared from 80.9 mm SL in juvenile C. macropus. Juveniles of the two species differed in dorsal fin shape and meristic characters. The occurrence of fertilized eggs in waters off Wakayama Prefecture, Japan indicated that C.macropus and P. nudarcus both spawn in Kuroshio waters.