Estado da arte das raias na bacia do alto rio Paraná (Chondrichthyes, Potamotrygonidae)

Abstract

The occurrence of the freshwater stingrays, Potamotrygon amandae and Potamotrygon falkneri, in the upper Paraná River basin represents one of the most significant recent changes in the distribution of neotropical ichthyofauna, resulting from the elimination of the biogeographic barrier of Sete Quedas Falls after the making of the Itaipu Reservoir. This study aimed to provide a state of the art review of these species in the upper Paraná river basin, addressing aspects related to their natural history, distribution, morphology, physiology, reproduction, conservation status, accidents involving humans, and ecological impacts associated with their expansion. Therefore, a literature review was conducted based on scientific articles, books, theses, dissertations, and technical documents. The analyzed studies indicate that these species show high ecological plasticity, broad adaptability to different habitats, and specialized reproductive strategies, characteristics that have favored their establishment and dispersal throughout the upper portion of the Paraná River. Furthermore, their presence has been associated with ecological changes and an increase in accidents involving fishermen and swimmers, representing an important challenge for environmental management and public health. Thus, the synthesis of available information contributes to expanding knowledge about these species and provides support for future monitoring, conservation, and environmental education initiatives.