IN VITRO CONSUMPTION OF CAULERPA TAXIFOLIA (CHLOROPHYTA) BY ACCUSTOMED AND NON-ACCUSTOMED PARACENTROTUS LIVIDUS (ECHINOID): SEASONAL VARIATIONS

摘要

In vitro short time experiments (a few weeks) show that daily ingestion by Paracentrotus lividus (Echinodermata: Echinoidea) is weak (0-81 mg DW d~-1 ind~-1) for Caulerpa taxifolia (Chlorophyta), compared to the data recorded with an almost totally avoided brown alga, Cystoseira compressa (24-137 mg DW d~-1 ind~-1) and with a preferred brown alga, Halopteris scoparia (79-397mg DW d~-1 ind~-1). There is no significant difference between spring (when the toxic metabolite content is at its minimum) and summer-autumn (when it is at its maximum). In contrast, the absorption rate of the sea urchin fed on Caulerpa taxifolia is significantly weaker in spring than in summer-autumn.