Embryonic and larval development of big-scale sand smelt Atherina boyeri (Atherinidae)
The embryonic and early larval development of the laboratory-reared big-scale sand smelt, Atherina boyeri Risso, 1810 are described. Mature unfertilized eggs were pelagic and spherical with a homogeneous and unsegmented yolk containing several oil droplets. Eggs were equipped with long filaments. Fertilized eggs ranged in diameter from 1.58 to 2.05 mm, with a mean (± SD) of 1.75 ± 0.10 mm. Embryonic development lasted 211 h 32 min at a mean temperature 19.2°C. Newly hatched yolk-sac larvae measured 4.5 ± 0.15 mm total length. The yolk was completely absorbed by day 3 after hatching. Changes in length and shape of yolk-sac larvae and larvae during the first six days after hatching are also presented.