Bulbostylis somaliensis Lye (Cyperaceae) is described from Somalia. It is closely related to B. hispidula (Vahl) R. Haines, but differs in its smaller achenes as well as in the shape and surface structure of the achenes. The major diagnostic characters are the non-triangular achene and the outermost cells to the pericarp, which have several papillae in each cell. Three subspecies are distinguished, viz. subsp. somaliensis, subsp. confusa Lye and subsp. microcarpa (Chiov.) Lye.