Data for: Ichthyofauna of streams in Maringá municipality, Paraná, Brazil: an updated checklist, threats, and conservation perspectives

Maringá is a planned municipality, built on a plateau that divides two major hydrographic basins, the Ivaí and the Pirapó/Paranapanema, both of which are part of the Upper Paraná River system. The following list comprises the most recent taxonomic survey of fish species inhabiting these specific tributaries, based on material from the NUP fish collection and the available literature. A total of 81 species were identified, distributed across 24 families and six orders. The most species-rich order is Characiformes, comprising 34 species. The analyzed data revealed that 11 species were recorded as non-native, highlighting the alarming occurrence of introduced species, particularly those associated with the aquarium trade. Regarding the threat categories assessed by the IUCN, only one species, Bryconamericus coeruleus, is considered Near Threatened. In addition, a noteworthy feature is the presence of seven putative new species, underscoring the need for further studies to enable a more comprehensive understanding and description of the region’s ichthyofauna. The results of this study indicate that the composition of fish species in the streams of the municipality of Maringá is diverse and taxonomically complex. Further investigations are required to address the aforementioned conservation issues and the potential description of new species. Moreover, additional research in the Ivaí River basin is needed to expand species records, especially in urban streams. We hope that this checklist of freshwater fish species from the municipality of Maringá will serve as a useful source of information for decision-makers and for those interested in developing plans to manage and protect the region’s fish fauna.