Resultaten van een NMV-excursie naar het Maasdal en het Viroindal (België). Aangevuld met vondsten tijdens eerdere bezoeken aan deze gebieden

In October, 2022, two groups of members of the Netherlands’ Malacological Society (NMV) visited the Meuse valley near Hastière and the Viroin valley near Olloy-sur-Viroin, at the invitation of Peter and Margret Breeman who live there. The reason for these excursions was the greatly reduced water level in the Meuse due to maintenance work. In this article we report the results. Moreover, we have added additional findings by the authors from previous visits to the same areas. In the Meuse valley, mainly near Hastière-Par-Delà, 32 species of freshwater molluscs were found and 49 species of terrestrial molluscs. Remarkable was the discovery of living specimens of the Thick shelled watermussel Unio crassus Philipsson, 1887. From the Viroin valley near Olloy-sur-Viroin the authors report 70 species of terrestrial molluscs.