Graemontia viridiceps n.sp., is described from the southwestern part of South Africa. This is the seventh species of the genus and the second species for which male genitalia are described and illustrated. A key is given to all species of Graemontia. This genus is important for studying phylogenetic relationships within the family Triaenonychidae because, although traditionally placed in the tribe Triaenonychini, it shares some derived similarities with members of the tribe Triaenobunini, which is absent from Africa. If, as suggested, Graemontia is the sister group of the Triaenobunini, it provides corroboration for the biogeographical sequence (South Africa (southern South America, Australia, New Zealand)).