Sinanodonta woodiana originates from East Asia. Since the first records in Romania in 1979 the species has expanded its range to 16 European countries, including Belgium. Currently, observations seem to be limited to the eastern part of Flanders. The first Belgian specimens were found in 1999 in a recreational pond in Diest. Additional specimens were collected in ponds in Zonhoven (2001), Oud-Heverlee (2001) and most recently in Genk (2009). These ponds are all connected to rivers belonging to the Schelde catchment, which may facilitate further colonization of Belgian waters. The populations seem to be persistent, as several age classes were found. Introductions of fish for angling purposes or to remove aquatic vegetation are likely to be the main cause of its dispersal to isolated ponds and river basins. The larvae (glochidia) are parasites of fish gills and the species is therefore introduced together with fish restocking. Considering its rapid range expansion, S. woodiana is regarded as an invasive species. The presence of the species could have adverse effects on indigenous unionids. It occurs in the same habitats and may compete for resources such as food and space. There are indications that S. woodiana is more tolerant to low oxygen concentrations and has higher recruitment than indigenous mussels. These characteristics offer competitive advantages over native unionids and may explain its success in European waters. In some European locations S. woodiana has become more abundant than native unionid species. Richerzhagen, C. & Van den Neucker, T. (2009). Chinese vijvermossel duikt op in De Maten. Natuur.focus 8(1):36. Sablon, R. (2002). Exotic mussel species invasions in Belgian freshwater systems (Mollusca:Bivalvia). Bulletin van het Koninklijk Belgisch Instituut voor Natuurwetenschappen 72(Suppl.):65-66.