The fig-breeding drosophilids of tropical Africa include 19 spp. in the genus Lissocephala which appears to be endemic to the tropical African region and 16 spp. in the Drosophila fima species group which is unequivocally endemic to this region. The Lissocephala spp. are strictly restricted to immature figs for breeding; the D. fima group species are confined to post-matured figs though some of the latter are not obligatory fig-breeding species. Speciation in Lissocephala is hypothesized to have proceeded from conergent evolution with the obligatory pollinating fig wasps. The Lissocephala radiation seems to have been an evolutionary by-product of the fig/fig wasp co-speciation; this genus, probably the oldest within the family. Drosophilidae, has a long evolutionary history on the African continent. Lissocephala speciation is assumed to represent a fundamentally different evolutionary event than speciation within the D. fima species group.
Lachaise, D., Tsacas, L., & Couturier, G. (1982). The Drosophilidae Associated with Tropical African Figs. Evolution, 36(1), 141. https://doi.org/10.1007/s00262-012-1264-y