Development of the Cottid Fish, Pseudoblennius percoides, Reared in the Laboratory, with Brief Descriptions of Juvenile P. marmoratus and P. zonostigma

Abstract

Embryonic, larval and juvenile development of the cottid fish, Pseudoblennius percoides were described on the basis of a series of laboratory-reared specimens. The eggs were demersal, adhesive, almost spherical in shape, measuring 1.66-1.82mm in diameter, and with numerous various-sized oil globules. Neighboring eggs adhered to each other to form an egg mass. Hatching occurred between 13 and 16 days after spawning at a water temperature of 15.4 to 16.5°C. Newly hatched larvae measured from 6.5 to 7.3mm, averaging 6.9mm TL, and possessed 40 myomeres. Absorption of the yolk was completed at about 7.5mm TL. Flexion of the notochord started and finished at about 10mm TL and about 14mm TL, respectively. Aggregate numbers of all fin rays were completed at over 16mm TL, when the larvae reached the juvenile stage. The pigment pattern became the same as that of adults in juveniles longer than 25mm TL. Lateral lines were completed at over 44mm TL, when the juveniles attained to the young stage. The early stages of this species were clearly distinguished from those of P. cottoides, and the juveniles of four Pseudoblennius species, i.e. P. percoides, P. cottoides, P. marmoratus and P. zonostigma, could be identified mainly by their pigment patterns.