Mytilopsis sallei Récluz, 1849

M. sallei, settled readily in the 1980s in Victoria Harbour, Hong Kong (Morton, 1989) and became a pest in the Pacific (Taiwan, Japan, Australia and Hong Kong). In the Indian coastal seas, this bivalve tolerates a wide range of environmental conditions, such as 108 mg L1 petroleum hydrocarbons (Mohan and Prakash, 1998) and 8.364 mg Zn L1 (Devi, 1995). Additionally, it tolerates 0–50 ppt salinity (Raju et al., 1975), and thrives in the presence of copper and tributyltin (Karande et al., 1993). As such, this bivalve, which has no natural predator in Indian coastal waters, attained nuisance status in Visakhapatnam harbour resulting in an annual biomass build up of 100 kg m2 (Rao et al., 1989). It has also spread into Bombay waters (Karande et al., 1993), displacing much of the native fauna, and may eventually cause drastic changes to the ecosystem. It has the potential to cause devastation in much of the Indian coastal waters by altering the trophodynamics and a loss in native biodiversity. (Subba Rao, @005).

In Visakhapatnam port, India (Ganapati et al., 1971; Morton, 1981), Hong Kong (Morton, 1989) and Taiwan (Liao et al., 2010), M. sallei causes severe fouling. Given their occurrence in such high densities, M. sallei could conceivably act as a biological filter to remove and consolidate particulate matter and plankton from the water. However, the beneficial or deleterious effects of such filtration to ecosystems remain unclear (see review by Sousa et al., 2009). Its congener M. trautwineana has been shown to have beneficial effects on shrimp aquaculture in Colombia when present in low densities by removing particulate matter; however, shrimp survival is reduced when the bivalves occur in high densities (Aldridge et al., 2008).