GENETIC-VARIABILITY AND RELATIONSHIPS FOR POPULATIONS OF CERASTODERMA-EDULE AND OF THE C-GLAUCUM COMPLEX

Genetic variability and relationships of populations of the cockles Ce rastoderma edule and of the C. glaucum complex in Europe were determin ed by means of isoenzyme electrophoresis. Distinct isoenzyme markers a llowed a clear distinction between these two taxa. C. edule showed a h igher genetic intra-population variability than the other cockle speci es. The imbalance of the genotypes within populations and the inter-po pulation differentiation of the C. glaucum complex are stronger than i n C. edule. The genetic variability is related to the different habita ts of the species, the members of the C. glaucum complex living in mor e isolated areas and having more limited gene flow.