Temporal and seasonal variations in parasites of Metynnis lippincottianus (Characiformes: Characidae), a host from the eastern Amazon (Brazil)

Abstract

This study investigated the influence of temporal and seasonal variation (rainy/dry cycle) on the component community structure and infracommunities of parasites in Metynnis lippincottianus from the eastern Amazon (Brazil). A total of 8,774 parasites representing 9 species and 22,765 parasites representing 12 species was collected in 2011 and 2016 respectively, but only 42.8% of the species were common to both study years. In both years, there was a dominance of Ichthyophthirius multifiliis and the component community was 51% dissimilar. The species richness of parasites and the Berger–Parker dominance were higher in 2016, while the evenness and Brillouin diversity were higher in 2011. The prevalence and abundance of I. multifiliis and P. pillulare, as well as the prevalence of Contracaecum sp. were higher in the rainy season. The abundance of Anacanthorus strongylophalus, Urocleidoides sp., Dadayus pacupeva and Dadaytrema oxycephala was higher in the dry season. Infection with Procamallanus (Spirocamallanus) inopinatus was not influenced by the season, while by Trichodina sp. occurred only in the dry season and Ergasilus xinguensis only in the rainy season. The species richness of parasites, Brillouin diversity index and evenness were higher in the dry season, while the Berger–Parker index was higher in the rainy season. Temporal variation of communities and infracommunities of parasites was influenced by the body size of host populations and increase in anthropogenic impacts. Effect of seasons on environmental quality, host size and availability of infective stages of parasites were the determining factors in structuring the component communities and infracommunities of parasites.