Notocactus purpureus F.Ritter in Succulenta (Netherlands) 49: 109. 1970 Notocactus purpureus F.Ritter in Succulenta (Netherlands) 49: 109. 1970is basionym for Notocactus horstii f. purpureus (F.Ritter) K.Herm in Internoto 14: 64. 1993Taxon for this nameNotocactus purpureus F.Ritter