Abstract
Larval rearing and morphological observations were performed to qualify the biological chazacters in the early life stage of Japanese flounder Paralichthys olivaceus. Lazval development from hatching to metamorphosis was described in detail including squamation and fin develop-ment. Transformation from larvae to juveniles occurred between from 11.0mm to 12.5mm SL (SL), and eye migration was completed from 10.5mm SL. The eye migration was assumed to be completed when larvae were more than 17.0mm SL. Swimming speed of iarvae was re-corded at about 4.0mm/s for larval stage, and increased prior to morphological transition.
The change of morphometric characters was closely related with the developmental changes of transformation and eye migration, and with behavioral and ecological changes as well. It was consequently suggested that morphological developments of various organs were implicated in the functioaal significance and also the shift of the life pattern of ibis species.
