The identity of the dark species Zaprionus koroleu has long been problematic since its description by Burla (1954) from lowland rainforests in Côte d’Ivoire. It had often been confused with another montane dark species in Uganda (Buruga 1976) and Cameroon (Tsacas 1980; Bennet-Clark et al. 1980), which was later described as Zaprionus camerounensis by Chassagnard and Tsacas (1993). Chassagnard and Tsacas (1993) re-examined Burla’s type and considered the enlargement and fusion of BV on the scutellum a characteristic trait of Zaprionus koroleu in the lack of distinctive features of the male genitalia. However, the examination of different strains of Zaprionus vittiger has shown this character to be polymorphic and not exclusive to Zaprionus koroleu. Chassagnard and Tsacas (1993) also noted that Zaprionus koroleu is distinguishable from Zaprionus beninensis in having the thorax and abdomen darker than the frons, whereas in Zaprionus beninensis the abdomen is darker than the frons and the thorax as confirmed by re-examining the type series of Zaprionus beninensis. All species of the vittiger complex are found in high latitudes or altitudes with the exception of Zaprionus koroleu and Zaprionus beninensis. Burla (1954) noted that Zaprionus koroleu was bred in Côte d’Ivoire from decaying Raphia trunk along with other palm breeding drosophilids of the genera Chymomyza and Scaptodrosophila, and this was similar to the breeding niche of Zaprionus beninensis in Benin (fallen trunks of coconut palm; J. R. David, unpublished observations). Both species are, however, generalists as Burla (1954) bred Zaprionus koroleu also from fermenting fruits and as Zaprionus beninensis was maintained in laboratory for almost ten years (Chassagnard and Tsacas 1993). On the basis of these geographical and ecological considerations, only slight differences in pigmentation observed in Zaprionus beninensis and the great morphological similarity of male genitalia, Zaprionus beninensis Chassagnard & Tsacas syn. n. is considered a junior synonym to Zaprionus koroleu Burla.