Fish fauna from a fragmented river in the Atlantic Forest

Abstract: This study sought to identify the ichthyofauna composition of Muzambinho River, an upland tributary Paraná River. We also investigate whether waterfalls in region can serve as barriers dispersal fish species. For this purpose, collections were carried out at 34 points on River using different techniques. In all, 37 species recorded, some which endemic, and majority native. Among these species, are predominant degraded places be used bioindicators. The results demonstrate zonation that segregates fauna into three sessions separated by waterfalls: Lower Muzambinho, Upper Sao Domingos. conclude that, for ideal preservation it is necessary preserve its sections independently, would guarantee maintenance naturally isolated strains.