Perennial grasses commonly known as ‘spinifex’ (Triodia R.Br.) are iconic Australian plants, predominantly found in the arid interior of the continent. In some areas, such as the economically important Pilbara region of Western Australia, current species taxonomy does not account for observed diversity. Previous morphological and molecular studies of Triodia basedowii E.Pritz. and related species have revealed multiple unnamed lineages requiring taxonomic recognition. Here, we describe and name eight new species of Triodia, including T. birriliburu B.M.Anderson, T. chichesterensis B.M.Anderson, T. glabra B.M.Anderson & M.D.Barrett, T. infesta B.M.Anderson & M.D.Barrett, T. mallota B.M.Anderson & M.D.Barrett, T. nana B.M.Anderson, T. scintillans B.M.Anderson & M.D.Barrett, and T. vanleeuwenii B.M.Anderson & M.D.Barrett. We also provide recircumscriptions and revised descriptions for T. basedowii, T. lanigera Domin, T. concinna N.T.Burb. and T. plurinervata N.T.Burb. A key to species and photographs are included.