1. South America map showing the major river drainages. The detail show the collecting locations. The bold dashed line
in the detail indicates the limit of the last great marine incursion into South America (from the south) at approximately five
million years ago (modified from Frailey, 2002). The lighter dashed lines indicate the state-specific boundaries hosting the
collecting locations. MS1,2 = rio Miranda (state of Mato Grosso do Sul; 2n=46 and 2n=42); SP1 = rio Mogi-Guaçu (state of São
Paulo; 2n=44); SP2 = rio Tietê (state of São Paulo; 2n=42); SP3 = rio Paraná (state of São Paulo; 2n=42); PR1 = ribeirão Água do
Caixão (state of Paraná; 2n=46); PR2 = rio Tibagi (state of Paraná; 2n=42); PR3 = rio Paraná (state of Paraná; 2n=42).