While diving in Lake Grevelingen, a former estuary since 1971 largely separated from the North Sea by the Brouwersdam, the last two authors found a living specimen of the Variegated scallop Mimachlamys varia. Although the species was reported earlier from Oosterschelde and Grevelingenmeer, records are quite rare. Most likely a pelagic larva of the species was flushed in with sea water at Brouwerdam and settled near Dreischor in Lake Grevelingen (province of Zeeland).