Helminth community structure and diet of three Afrotropical anuran species: a test of the interactive-versus-isolationist parasite communities hypothesis

摘要

The interactive-versus-isolationist hypothesis predicts that parasitecommunities should be depauperated and weakly structured by interspecificcompetition in amphibians. A parasitological survey was carried out to testthis hypothesis using three anuran species from Nigeria, tropical Africa(one Bufonidae; two Ranidae). High values of parasite infection parameterswere found in all three species, which were infected by nematodes, cestodesand trematodes. Nonetheless, the parasite communities of the three anuranswere very depauperated in terms of number of species (4 to 6). Interspecificcompetition was irrelevant in all species, as revealed by null models andMonte Carlo permutations. Cluster analyses revealed that, in terms ofparasite community composition, the two Ranidae were similar, whereas theBufonidae was more different. However, when prevalence, intensity, andabundance of parasites are combined into a multivariate analysis, eachanuran species was clearly spaced apart from the others, thus revealingconsiderable species-specific differences in terms of their parasitecommunities. All anurans were generalists and probably opportunistic interms of dietary habits, and showed no evidence of interspecific competitionfor food. Overall, our data are widely consistent with expectations drivenfrom the interactive-versus-isolationist parasite communities hypothesis.