Abstract
The early life history of a sole Heteromycteris japonicus (Temminck et Schlegel) was studied in the western Wakasa Bay and adjacent waters, the Japan Sea.
General morphology of the larvae and juveniles ranging from 2.70 mm to 6.95 mm BL, was described. The characteristic features of this fish in early larval stages were distributional patterns of melanophores on the body surface, forming rows along the dorsal body contour extending from the head to tail and along ventral body contour from the abdominal region to the tail.
Eggs, postlarvae and juveniles were caught mainly in Yura River estuary and Maizuru Bay, and these areas may be their spawning and nursery ground.
Judging from gonad index and occurrence of eggs and larvae, actual spawning may occur in the western Wakasa Bay during the period from May to July.
Food items of the gut contents were as follows: copepods nauplii and small copepods in early larvae, copepods and crustacean larvae in metamorphosis, and amphipods and amphipods and copeopods in early juveniles.
