Community Structure of Helminth Parasites of Leptodactylus bufonius (Anura: Leptodactylidae) from Northeastern Argentina

Abstract

The main goals of this study were to determine the richness and diversity of helminth parasites of Leptodactylus bufonius at the component and infracommunity levels and evaluate whether the composition of the parasite community is determined by biotic and abiotic factors. In total, 76 specimens were collected near the city of Corrientes, Corrientes Province, Argentina. The helminth component community in L. bufonius in this area was comprised of 16 species. The predominant groups of helminth parasites (larval and adult) were trematodes (50%) followed by nematodes (38%); other groups of parasites were represented by only 1 species (Cestoda: Cylindrotaenia sp. and Acanthocephala: Centrorhynchus sp.). Helminth species showed unequal abundances with a typical aggregated pattern of distribution. The prevalence of infection was 93% in specimens of L. bufonius examined. The main helminth species in the community was Aplectana hylambatis (importance value: I = 96.41), followed by Catadiscus inopinatus (I = 2.32). At the infracommunity level, the mean individual species richness was no more than 3 helminth species per infected host; the diversity and equitability of helminths were 0.18 ± 0.14 and 0.44 ± 0.32, respectively. The host body size was the main factor in determining the infrapopulation structure of various helminth species. Species richness was significantly and positively correlated with the host body size. Data revealed significant positive correlations between helminth species (Cat. inopinatus/Centrorhynchus sp. and A. hylambatis/Centrorhynchus sp.). A significant negative correlation was observed between A. hylambatis and C. podicipinus. Only 2 associations were found among the 7 species considered. The parasite community of L. bufonius showed wide variations in its helminth fauna and included helminths of aquatic and terrestrial habitats. The correspondence between host habits and parasite biology is reflected in the parasites harbored by these amphibian hosts.