A new species of moth-fly, Tonnoira igrapiunensis sp. nov. (Psychodidae, Psychodinae), from the Brazilian Atlantic Rain Forest is described. The new species can be distinguished from other species of the genus by its eye bridge separated by 0.5 facet diameter, R₅ ending slightly posterior to apex of the wing, gonostyli bifurcated with long arm shorter than length of gonocoxites, aedeagus bipartite and asymmetrical, and two asymmetrical parameres. The gonostylus is similar to that of Tonnoira andradei Santos, 2014, but in the latter species the aedeagus has only one shaft and not two as in the new species. Tonnoira bifida Bravo & Chagas, 2004, Tonnoira brisolaii Santos, 2014, and Tonnoira galatiae Santos, 2014 have their distribution expanded.