Clonal diversity and rockpool size in the marine ostracod, Callistocytherebadia

Samples containing the marine ostracod Callistocythere badia were collected from upper shore rockpools on Filey Brigg, nor th-cast England in order to examine the life cycle and genetic structure of the species. Reproduction occurred during spring/summer after which the adults died; juveniles over-w intered as A-1 instars. No males were ever found during the study. Analysis at three polymorphic loci (Gpi, Pgm and Mpi), showed significant deviation s from Hardy-Weinberg equilibrium, and significant linkage equilibrium at a nd between all loci. The genetic data and absence of malts confirm that Cal listocythere is an asexual species. There was a significant positive relati onship between the number of clones found within a pool and rockpool size, but not with algal habitat heterogeneity.