General morphology of the eggs, larvae and juveniles of a flounder
Kareius bicoloratus were described. There is some variation in relationship between stage and body length in larvae, especially at the metamorphosis stages. It may mean the variation in the size at settlement.
Judging from records of occurrence of eggs, actual spawning period may be from January to February. Annual occurrence of larvae was surveyed by means of underwater fish lamp, and it appeared that the number and periold of larval occurrence at the inner part of Maizuru Bay showed remarkable variations from year to year during 1974-1979.
Eggs were caught in he offshore region of the mouth of the Yura River, prelarvae were also caught in the same region, early postlarvae were around the mouth of Maizuru Bay, late postlarvae were mainly in the Maizuru Bay, and nearshore region of the mouth of the Yura River. Early juveniles were captured in the water closs to the shore of the Yura River and Maizuru Bay, and these areas may be their nursery ground. These facts indicate that an inshore movement took place during the larval stage.
Analysis of the gut content showed that the food items were copepod eggs and nauplii in early postlarvae, copepods (mainly
Centropages sp.) in late postlarvae, and mysids and amphipods in early juveniles.
The early life histories of two species,
Kareius bicoloratus and
Limanda yokohamae, were compared.
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