Embryonic, larval, and juvenile development of reared Cobitis striata fuchigamii (Cypriniformes: Cobitidae)

Abstract

In this study, the early development of Cobitis striata fuchigamii was described using aquarium-spawned eggs and juveniles. Egg yolk diameter after water absorption was 1.0-1.1 mm, and the spherical, demersal eggs had a light-yellow yolk, no oil droplets, and low viscosity. Newly hatched larvae [4.0-4.5 mm in total length (TL)] had 44-45 (27-28 + 17-18) myomeres (26-27 between the pectoral fins and the middle of the anus), two pairs of short tubular outer gill filaments on the cheek, and only a few melanophores on parts of the eye. Notochord flexion began at 5.1-6.8 mm TL and ended at 10.0 mm TL. The number of fin rays on each fin was finalized at approximately 25.0 mm TL. Lateral line spots of the larvae were indistinct, and juveniles formed blotches at approximately 25.0 mm TL. The barbels were formed in the following order: third, second, and then first. The formation of membranous fins occurred in the following order: pectoral, caudal, dorsal, anal, and then pelvic; full fin ray complements occurred in the caudal, dorsal, anal, pectoral, and pelvic regions. Some individuals (5.1-7.5 mm TL at the flexion stage) had free lateral neuromasts on the caudal region, each with a short cupula.