Elmidae is one of the most diverse families of aquatic beetles, with more than 1500 species in 151 genera. The Neotropical genus Portelmis formerly comprised five species known from Central and northern South America, divided into two species groups. Three new Brazilian species from the nevermanni group are described and illustrated here: Portelmis vanini sp. nov., Portelmis krolowi sp. nov. and Portelmis fusariae sp. nov. New species records for the North, Central-West and Southeast of Brazil are presented. We also provide first SEM images and an updated key for Portelmis species.
Keywords: Coleoptera, aquatic insects, riffle beetles, South America, taxonomy.