A molecular characterization of species and populations of Dugesia gonocephala s.l.

We have employed a molecular approach to identify genomic characteristics in planarians belonging to Dugesia gonocephala s.1. In this paper we report the further characterisation of a repetitive DNA family (Del) that represents a useful molecular marker for establishing the genomic relationships among the species. We also describe the use of the molecular approach to obtain information about the genome organization of an asexual population of D. gonocephala s.1. from Montecristo Island, a natural park of the Tuscan Archipelago in the Tyrrhenian Sea. Specific DNA patterns have been individuated by using Southern blot analysis and the RAPD-PCR technique. These results, compared with those obtained in other species of Dugesia gonocephala s.1., indicate that some genomic differences characterise this geographically isolated planarian population. The possibility of a microspeciation event in the insular area is hypothesised.