The pupa and reared adult male of the Neotropical predatory midge Pellucidomyia oliveirai (Lane) are described, photographed and illustrated for the first time. The genus Pellucidomyia Macfie is reported for the first time from Argentina, and the adult female is redescribed and photographed. A key is provided for the three known species of pupae of Pellucidomyia. Details of the bionomics of all the species of Pellucidomyia are discussed and their distributions plotted on a world map.