Freshwater mussels are among the most imperiled animals worldwide. These unionids tend to be most abundant in flowing streams and rivers. The distribution of unionids is often patchy, clumped, or otherwise irregular. Native freshwater bivalves particularly belonging to the family Unionidae are widely distributed in North America with 297 recognized taxa (William et al 1993). Of these 297 known taxa only 70 are considered to be stable. The greatest species diversity occurs in the southeastern US (Neves 1987) which has more freshwater mussel species than any other region of the world . All of South Carolina’s freshwater mussel species belong to the family Unionidae. Of these, 26 species are in the SC DNR’s CWCS priority species list (Kohlsaat et al. 2005), and several of these occur in the Savannah River Basin.
Johnson, Alan and Mhatre, Snehal, "Water for Electricity in the Upper Savannah Basin: Impacts on Freshwater Mussels" (2014). Clemson's Biological Science's Annual Student Symposium. 2.