Rio Boguaçu is a river located in Paraná, Brazil, flowing within the coastal zone near Baía de Guaratuba — one of the most productive estuarine systems along Brazil's southern Atlantic coast. Situated in a region where freshwater rivers meet the rich brackish waters of the bay, Rio Boguaçu offers anglers access to a dynamic coastal fishery shaped by tidal influence, dense Atlantic Forest riparian vegetation, and the productive mixing of freshwater and saltwater environments. The river is part of a network of waterways draining into Baía de Guaratuba, making it a notable destination for anglers targeting coastal and estuarine species in southern Paraná.