New records of Assiminea grayana Fleming, 1828, Myosotella myosotis (Draparnaud, 1801) and Pisidium subtruncatum Malm, 1855 (Mollusca: Gastropoda, Bivalvia) in the Scheldt estuary

The mollusc fauna of the tidal marshes along the river Scheldt was investigated. To this end, 31 marshes were sampled along a salinity gradient from Berlare (Belgium; freshwater) to Vlissingen (the Netherlands; marine). Our faunistic survey yielded eight new localities for the caenogastropod Assiminea grayana, of which seven in the Belgian part. In the marsh of Doel ("Prosperhaven") we discovered the first inland population of the pulmonate mollusc Myosotella myosotis, a species which in Belgium was hitherto only known from three coastal localities. Finally, additional records of Pisidium subtruncatum for the Scheldt estuary are reported.