Descriptive morphology of the reared eggs, larvae, and juveniles of the marine atherinid fish Atherinomorus duodecimalis

Embryonic, larval, and juvenile development of the marine atherinid Atherinomorus duodecimalis are described from laboratory-reared specimens. The eggs, measuring 1.15-1.24 mm in diameter, were demersal and almost spherical in shape with numerous chorionic filaments. Hatching occurred 7 or 8 days after spawning, the newly hatched larvae measuring 4.5-5.1 mm in body length (BL) and having 5+34=39 myomeres. Notochord flexion started at 6.9 mm BL and finished at 8.3 mm BL. Aggregate numbers of all fin rays were completed by 14 mm BL. Eggs of this species could be distinguished from other known atherinid eggs on the basis of egg diameter and the arrangement, length, and number of chorionic filaments. Larvae were also distinctive in myomere counts, pigmentation, and locations of the anus and second dorsal fin origin.