The types of Gibbula nehalenniae van Regteren Altena, 1954 (Mollusca, Gastropoda) re-investigated

The specimen in the Naturalis collections labelled as holotype of Gibbula nehalenniae van Regteren Altena, 1954 is actually a juvenile specimen of Gibbula octosulcata (Nyst, 1835). It is demonstrated that an unfortunate and so far unnoticed mix-up has occurred. To ensure a future stable nomenclature in a group of closely similar species, including G. nehalenniae and G octosulcata, a neotype for G. nehalenniae is designated, described and illustrated. A summary of the remaining type specimens of G. nehalenniae is added.