Fig. 3

Mean total prevalence + SD (% infected ind. from total sample) of trematode infections and mean total intensity + SD (number parasite ind. per infected host) of metacercarial trematode stages in mollusc host species. For the three gastropods, only trematodes utilizing gastropods as first intermediate hosts were considered. “Sites” were used as replicates, hence n = 2–6 (see Table 1). x not determined