The purple bankclimber is a large fresh water mussel that can reach a length between 4-5.5 inches (10-14 centimeters). This species has a nearly rhomboidal (only opposite sides of shell are equal in size) shell, with a well-sculpted grey to black colored outer section and an inner shell that is white but transitions to purple towards the shell edge. The left valve contains two teeth and the right valve contains one tooth (Florida Natural Areas Inventory 2001).