Neoporteria islayensis f. spinosior (Rauh & Backeb.) Donald & G.D.Rowley in Cact. Succ. J. Gr. Brit. 28: 56. 1966
Neoporteria islayensis f. spinosior in Cact. Succ. J. Gr. Brit. 28: 56. 1966
is new combination for Islaya grandiflorens var. spinosior