Possible cryptic speciation within the sea anemone Actinia equina complex detected by AFLP markers

The population genetic profiles of 60 specimens of the common intertidal sea anemone Actinia equina taken from four sampling sites (Peroj, Barbariga and the north and south shores of the Limski Canal), along a 25 km strip of the coast of the Istra Peninsula, Croatia, were evaluated by AFLP markers (144 loci). All populations were characterized by aggregates of specimens confined within a few square meters. One of the populations (on the north shore of the canal) contained both large and small-sized individuals. Results revealed high within-aggregate genetic heterogeneity (36.1-55.6%). With respect to interpopulation profiles, geographically remote populations from Peroj, Barbariga and the south shore of the canal were more closely related genetically than those on the north and south shores of the canal. The small-sized subpopulation from the north shore exhibits a distinct AFLP pattern, suggesting that it warrants recognition as a cryptic species.