Redescrição de Potamolithus catharinae com base em topótipos (Gastropoda, Hydrobiidae), rio Hercílio, Santa Catarina, Brasil

Potamolithus catharinae Pilsbry, 1911 is characterized on specimens from Hercilio river, State of Santa Catarina, Brazil, type-locality. Conchology, conchometry, soft-part morphology including head and food complex, pallial structures, radula and some aspects of the female and male reproductive systems are provided.