THE PRODISSOCONCH OF PECTEN-MAXIMUS (MOLL USCA, BIVALVIA) - A POTENTIAL TOOL FOR ESTIMATING RECRUITMENT

Analysis of the larval shell of Pecten maximus provides valuable infor mation in several fields. For example, it is morphological characteris tics which make it possible to distinguish larvae in the plankton. How ever it is mainly the hinge which represents the best criterion for la rval diagnosis. Morphogenesis of the hinge can be used to establish th e age of veligers. On the other hand, striation does not seem to corre spond to any rhythmicity which would allow age determination. The inte rvalve distance for a shell height of 90 mum, the Dim90, is, at the pr esent time, the best known index for the estimation, from the earliest days of pelagic life, of the larval growth potential, survival and me tamorphosis competence.