Freshwater micro-gastropods from the Iguaçu National Park, Brazil: two new truncatelloid caenogastropods and anatomy of Chilina megastoma Hylton Scott, 1958

Abstract

Collecting in Foz do Iguaçu National Park, Paraná, Brazil, an important tourist region with preserved rainforest, has revealed three micro-gastropod species which required morphological and taxonomic studies. One of them is a chilinid Chilina megastoma Hylton Scott, a member of a poorly studied group. Another two are new species of truncatelloid caenogastropods: Potamolithus mirim n. sp. and Heleobia iguassu n. sp. The three species are described in detail and discussed from taxonomic and phylogenetic point of view. As they are highly endemic, protective measures are suggested. Key woRdS: Mollusca; systematics; morphology; taxonomy