Induction of Spawning, Larval Development and Growth of the Top Shell, Tectus pyramis in the Laboratory

Abstract

The spawning of Tectus pyiramis (Trochidae Gastropoda), caught off Hachijo Island, was induced using 35% hydrogen peroxide (0.01 ml/l) and heating. Hatching, formation of larval shell and settlement occurred 10, 20 and 50 h after fertilization, respectively. Metamorphosis to juvenile occured at 60 h after fertilization in 24.8-25.7°C. No larval hatching was observed in 16.8-17.5°C and the shell was incompletely formed in 20.0-21.4°C. Mean shell diameter was 16.3 mm at one year and 46.1 mm at two years after fertilization.