Isbrueckerichthys duseni:

Brazil: Paraná State: rio Ribeira de Iguape basin: MCP 20128, 14, 23.5-95.2 mm SL; rio Piedade on road from Rio Branco do Sul to Açungui, ca. 26 km WNW of Rio Branco do Sul. - MCP 12557, 20 (7), 28.6-98.8 mm SL; ribeirão Pulador, 3 km S of Campinhos on highway BR 476, Cerro Azul. - MCP 12564, 28 (7), 23.8-91.1 mm SL; ribeirão Pocinha, 4 km S of Tunas on highway BR 476, Bocaiúva do Sul.