A new species of Apareiodon is described from the Rio Piquiri, upper Rio Paraná basin, State of Paraná, Brazil. This species occurs syntopically with one congener, A. piracicabae, with whom it shares the coloration pattern without dark vertical bands and/or blotches below lateral-line region but differs in the premaxillary teeth form, which is more pointed, and maxillary teeth number (one instead of two). However its morphological features, mainly teeth, are similar to A. ibitiensis, another congener that inhabits the upper Rio Paraná basin. Comparative diagnoses between the new species and the similar congeners based on aspects of coloration and morphology are provided.