Embryonic and larval development of Babylonia formosae habei(Altena and Gittenberger, 1981)(Gastropoda: Buccinidae) on China's coast

The development of embryos and larvae of Babylonia formosae habei living along the southeast coast of China is observed under laboratory conditions.The egg masses are laid by females on hard substrate at night and each capsule contains 100-500 eggs.Each egg is 250-280 mm in diameter.The first two cleavages of the embryo are meridional and equal,and a polar lobe is produced.Larval kidney,which only consists of a single cell,appears during the gastrula stage on each side of the embryo.The right tentacle develops prior to the left one.At 25-27℃,an intracapsulate veliger stage is reached about 4.5 d after deposition.The larvae hatch on the fifth day as swimming veligers with a shell length of 360-500 mm.The newly hatched larva can ingest suspended algal cells from the water column and remains in the pelagic stage for 8-10 d.The newly settled juveniles are 900-1 200 mm in shell length.