The small genus Xenoscapa (Goldblatt) Goldblatt & J.C.Manning, endemic to the southern African winter rainfall region, is reviewed. The new species X. grandiflora is described from the deeply dissected southern part of the Huib Hoch Plateau in southern Namibia. It differs from the two known species in the genus in its significantly larger, pale lilac flowers. Full descriptions and accounts of all three known species are provided, with distribution maps and illustrations. Keywords: Iridaceae, new species, southern Africa, taxonomy, Xenoscapa (Goldblatt) Goldblatt & J.C.Manning.