The systematic status of Rhipicephalus species whose males have tricuspid adanal plates has been confused for many years. Some authors have regarded Rhipicephalus tricuspis D/Snitz, 1906 as the only valid entity with this morphological character and synonymized both Rhipicephalus lunulatus Neumann, 1907 and Rhipicephalus glyphis D/Snitz, 1910 with it. Others, however, have always maintained that R. tricuspis and R. lunulatus (syn. R. glyphis) are separate species. Detailed comparative studies, including scanning electron microscopy, of laboratory-reared series as well as numerous field collections of these ticks have now confirmed that the latter view is correct. In addition, a third species, designated here as a 'Rhipicephalus sp. near tricuspis', has been identified as a member of this group.All stages of R. tricuspis and R. lunulatus are herein redescribed and illustrated by means of scanning electron micrographs. Their life cycles in the laboratory, hosts, distribution and disease relationships are discussed and their differentiation is described with the aid of line drawings.Rhipicephalus tricuspis has been recorded primarily in southern Africa, but also in Zambia and western Zaire, in various types of dry woodland. Its adults are most commonly parasitic on relatively small mammals such as hares, spring hares, jackals and small antelopes. R. lunalatus is much more widespread in the Afrotropical region, most commonly in different types of woodland but also in a variety of other habitats. Its adults parasitize a very wide range of hosts including domestic animals (especially cattle and dogs), the African buffalo, many different antelopes (especially the larger species) and wild pigs. The Rhipicephalus sp. near tricuspis occurs in eastern and parts of central Africa, where its distribution often overlaps with that of R. lunulatus.