In this paper, we provide a checklist of chironomids living in freshwater sponges in the upper Paraná River (Brazil) and we call attention to the problem of complete substitution of extensive areas covered by freshwater sponges by banks of the invasive alien species Limnoperna fortunei (golden mussel). We describe a new species of Oukuriella based on male adults and also describe an unusual larva of Chironomidae that probably belongs to the Stenochironomus complex.
Oukuriella; Stenochironomus complex; Limnoperna fortunei; Neotropical region