A phylogenetic classification of Grusonia, Opuntioideae, Cactaceae

A new classification proposal for the genus Grusonia is discussed and described. Three new sectional names are advanced following a recently published phylogenetic scheme derived from a five-plastid time-calibrated phylogeny. Two subgenera, Corynopuntia and Grusonia, and four sections, Radicaulenta, Xylocaulis, Grusonia and Spinicarpa are recognized, described, and discussed.