Sciaenids, commonly known as drums, are a group of coastal marine and freshwater fishes consisting of 275 species belonging to 70 genera that support commercial and sports fisheries around the world. Although most drums inhabit marine waters, the freshwater drum Aplodinotus grunniens Rafinesque; 1819 is the only sciaenid to exclusively inhabit freshwater environments. This species has the largest latitudinal range for freshwater fish in North America, with a distribution ranging from the Nelson River in Canada to the Usumacinta River, located between Mexico and Guatemala (Chad et al., 2007;Miller et al., 2005). Because of the economic importance of A. grunniens as a fishery resource,