A new genus, Prokius Nieves Aldrey, Medianero Nicholls, gen. nov., and two new species of oak gall wasps (Hymenoptera: Cynipidae: Cynipini), Prokius cambrai Medianero Nieves-Aldrey sp. nov. and Prokius lisethiae Medianero Nieves-Aldrey sp. nov., are described from adults reared from galls on Quercus bumelioides Liebm (Fagaceae, sect. Quercus, white oaks) collected in Panama. The new genus is phylogenetically and morphologically close to Dros Kinsey and forms part of a large clade that includes species from several other genera that appear to require revision, including Andricus Hartig and Phylloteras Ashmead. Molecular and morphological data, diagnostic characters, gall descriptions, distribution and biological data of the new genus and the new species are given. This new genus represents the fourth recently described genus of Cynipidae endemic to the Neotropical region.