Freshwater Mussels (Mollusca, Bivalvia, Unionidae) of the Danube River Basin of Ukraine

During 2009–2011, 50 points of the Daube River Basin were surveyed. In 23 them, seven species Unionidae recorded: U. pictorum, tumidus, crassus sensu lato, A. anatina, cygnea, P. ?omplanat? and S. woodiana, which is an invasive species. Th e index occurrence freshwater mussels in general was 100 % Lower Danube (5 study areas), 42 Tisa (31 33.3 Seret (3 36 Prut (11 areas). rather low: 24 22 crassus, 16 14 complanata, 2 cygnea. not found river, while cygnea only there outside main watercourse. woodiana occurred sub-basin (with 83 20 frequency, respectively. mean values population densities ranged from 1.00 (A. cygnea) to 6.14 ind./m2 (S. woodiana), biomass varied 1.14 (P. ?omplanat?) 797.54 g/m2 woodiana).