We revised the species of the genus Pristomerus Curtis, 1836 in the Afrotropical Region. Fortynine species are recognized, of which 31 are newly described. The following new species are described: P. afrikaner, P. aka, P. babinga, P. bemba, P. dikidiki, P. herero, P. hutu, P. kagga, P. khoikhoi, P. kuku, P. masai, P. mbaka, P. mbama, P. mboum, P. nzakara, P. protea, P. restio, P. san, P. sara, P. sotho, P. swahili, P. teke, P. tutsi, P. venda, P. wolof, P. xhosa, P. yakoma, P. yangere, P. yoccolo, P. zande and P. zulu spp. nov. New synonyms: P. africator, P. cunctator and P. luteolus are new junior synonyms of P. pallidus. New records: new host records are reported for the widespread P. pallidus; new country-level distribution records are added for P. bullis, P. keyka, P. kelikely and P. pallidus; and reports of Trathala concolor and P. veloma in South Africa are shown to have been erroneous. An illustrated dichotomous key to females is provided; an online Lucid interactive matrix key is also available at www.waspweb.org. Finally, the ecological and geographical correlates of colour patterns exhibited by Pristomerus in the Afrotropical region are discussed.
Africa, Hymenoptera, identification key, parasitoid wasp, solitary koinobiont endoparasitoid.