Diversity and dynamics in larval digenean assemblages parasitizing Heleobia parchappii in a freshwater shallow lake from the Southeastern Pampa plain, Argentina

Abstract

Digeneans have important roles within ecosystems, however, it is estimated that only 14% of the species have been described. Therefore, before being able to detail their role, digenean species identification and the diversity present in the ecosystems must be known. In this study, the diversity and the temporal-spatial dynamics of larval digeneans in the freshwater snail Heleobia parchappiiwere analyzed in a shallow lake. Specimens of H. parchappiiwere collected seasonally at three points during one yearand a total of 2,871 molluscs were analyzed. A total of 23 species of digenea were registered and both the overall prevalence and the composition of the assemblages presented temporal and spatial variations, responding to the differential environmental conditions characteristics (anthropic effect, presence of native forests, and differential use of the habitat by the definitive hosts) of three sampled sites. The assemblages of larval digenean in their first intermediate host support the idea that this areais of great importance in biodiversity, and could be endemic areas of some species of digenean that use reptiles, amphibians, and bats as hosts, groups that are at risk of conservation. Protection of these environments is a fundamental pillar in the policies for the conservation of wild flora and fauna.