Subsídios para o conhecimento de Laevapex diaphanus (Haldeman, 1841) (Mollusca: Basommatophora: Ancylidade)

Abstract

This study deals mainly with the anatomy fo Laevapex diaphanus (Haldeman, 1841), in comparison with Laevapex fuscus (Adams, 1841). L. diaphanus maybe distinguished from L. fuscus by the asmymmetric central tooth in the radula, smaller seminal vesicle, prostate and ovotestis , less pronounced mantle pigmentation The structure of the penial complex without flagellum, with a well-developed ultra-penis and lateral penis pore, and a conspicuous hollow core of black pigment in'the tentacles, distinguish Laevapex very clearly fron the south America genera. The interrelationships between Laevapex and these genera are discussed. The genus Laevapex is recorded for the first time in Brazil.