Two small species of the genus Retinella from the Western Alps (Mollusca: Pulmonata: Zonitidae)

A few taxa of the Zonitidae from N-W Italy may be presently confused, because of the shell characters, with Aegopinella pura (Alder). However, they are clearly distinguished from the latter by anatomical features. These features suggest their being placed in the genus Retinella Fisher. Thus Retinella pseudoaegopinella is described as a new species, and Hyalinia stabilei Pollonera is confirmed as a good Retinella species. These two Retinella show anatomical and shell characters which do not fit in with those of the subgenerical taxa now in use. This constitutes an indication that the validity of subgenera should be reconsidered.