According to the analysis of HAT-RAPD patterns, the similarity index between P.epiclitum and O.streptocoelium was 0.2286, between P.epiclitum and F.elongatus was 0.0645, between O.streptocoelium and F.elongatus was 0.0500. The phylogenetic tree was built using the parsimony method by PAUP program with S.falcatus as outgroup (Fig. 2).