A comparison of reproduction and juvenile growth and development between Babylonia areolata and B.formosae

Artifical reproduction of Babylonia areolata and B.formosae were taken in this study. The egg capsules of this two Babylonia were held in water temperature 23.6±1.1℃, the hatching time for B.areolata was 7 d and the shell length of firstborn larvae was 482.7±10.6 μm, while the hatching time for B.formosae was 8 d and the shell height of newly hatching larvae was 398.2±10.3 μm. The larvae were reared at 0.1~0.2 ind · mL^-1 in water temperature 25.2±0.9, the growth rate of larval shell height for B.areolata was 33.6 μm · d^-1 and larvae began metamorphosis when the larval shell height reached 1 323.9±118.6 μm after rearing 18 d, while the growth rate of larval shell height for B.formosae was 25.3 μm · d^-1 and larvae began metamorphosis when the larval shell height reached 955.5±174.4 μm after rearing 16 d. The juveniles were reared at 2 100 ind · m^-2 in water temperature 26.5±0.7℃, the growth rate of shell height for B.areolata and B.formosae were 0.21 and 0.20 mm · d^-1, respective.