Gymnocactus ysabelae (Schlange) Backeb., Cactaceae 5: 2856. 1961 Gymnocactus ysabelae (Schlange) Backeb., Cactaceae 5: 2856. 1961is new combination for Thelocactus ysabelae Schlange in Cact. Succ. J. (Los Angeles) 5: 551. 1934Taxon for this nameGymnocactus ysabelae (Schlange) Backeb.