A new species of Trisetum Pers. (Poaceae, Aveneae), T. tamonanteae Marrero Rodr. & S. Scholz, from Fuerteventura, Canary Islands, Spain, is described. We discuss its affinities to related taxa, and provide information about its habitat and ecology, noting its possible ability to reproduce vegetatively by pseudoviviparism, as well as the conservation status of its populations. This is the first reference to Trisetum s. str. for the Canary Islands and the whole of Macaronesia.