Mitochondrial 16s rDNA was sequenced from nine different populations of Aphelinidae and 10 of aphidiinae. Sequence divergences between populations within a species are low, ranging from 0 to 0.38%. Divergences among species within the same genus range from 0 to 8.71%. Aphelinus asychis Walker has a sequence divergence from the other Aphelinus spp. of 8.71%, which is even higher than the divergences among the aphidiine genera Lysiphlebus, Aphidius and Diaeretiella. Our 16s rDNA phylogeny for aphidiines is concordant with a previously published NADH1 dehydrogenase phylogeny. Our analysis identifies a complex comprising A. albipodus (Hayat & Fatima), A. varipes (Foerster), and A. hordei (Kurdjumov). The sequence divergences within this complex are low, ranging from 0 to 0.38% with an average of 0.19%, which suggests that the three species within the A. varipes complex diverged within the last ≈90,000 yr.