HATCHERY PRODUCTION OF DIPLOID AND TRIPLOID CLAMS, TAPES-DORSATUS (LAMARCK 1818) - A POTENTIAL NEW SPECIES FOR AQUACULTURE

To assess the potential for hatchery production of the venerid clam, T apes dorsatus, diploid and triploid clams were produced and ongrown un til the spat reached 5-8 mm in size. Triploidy percentages at metamorp hosis that ranged from 56 to 85% were induced using a 15-min exposure to 1 mg/1 cytochalasin B. No differences were observed in the growth r ate of sibling diploid and triploid T. dorsatus larvae. Survival of di ploid clams to pediveliger stage was however higher. Post-metamorphic growth and survival of diploid and triploid clams remained the same un til the clams were removed from the hatchery to outdoor nurseries. Thr oughout the larval and early spat phases of production, T. dorsatus gr owth was similar to that reported for the Manila clam, Tapes philippin arum. Based upon its ease of culture, rapid growth and marketability, T. dorsatus are thought to have considerable aquaculture potential.