Nematodes of Proceratophrys ararype (Anura: Odontophrynidae), an endemic frog from the Araripe Plateau, northeastern Brazil

Abstract: Parasites are an important component of the global biomass, having significant roles in several regulatory mechanisms in the ecosystem. Parasitism is one of the most common ecological interactions on the planet. Studies have shown that the helminth fauna of only 8% of amphibian species in Brazil have been studied, and this percentage is lower for the Odontophrynidae family, with only four of the 50 species kown to occur in Brazil having been investigated. Here, we present the helminth fauna of Proceratophrys ararype, an anuran endemic to the “Brejo de Altitude” Chapada do Araripe (Araripe Plateau), northeastern Brazil. The infection parameters analyzed were prevalence, mean intensity of infection and mean abundance of parasites. We used the Pearson’s linear correlation coefficient to check the correlations between the abundance of the parasites with the snout-vent length (SVL) of hosts. To verify the degree of aggregation of parasites in hosts, we used the dispersion index. Out of 40 specimens examined, 19 specimens were infected with at least one parasite. The overall prevalence was 47.5% with a mean infection intensity of 18.93 ± 10.77. The endoparasitic community associated with P. ararype consisted of six species of parasites, with Falcaustra mascula having the highest prevalence (25%). Most parasites had a uniform dispersion index in the hosts and their abundance was unrelated to host size. Here, we also present a compilation of all parasites associated with host species of the genus Proceratophrys from South America. Overall, we found 23 species of parasites associated with five host species (P. ararype, P. appendiculata, P. boiei, P. cristiceps, P. mantiqueira). Of these, two species of parasites (Oswaldocruzia mazzai and Strongyloides sp.) represent new records for the genus Proceratophrys. Our results demonstrate the lack of studies on amphibian helminth fauna and fill an important knowledge gap on the diversity of parasites of Proceratophrys ararype, an endemic frog from the Araripe Plateau, northeastern Brazil.