Notocactus ottonis f. elegans (Backeb. & Voll) Havlíček in Repert. Pl. Succ. 14: 11. 1990
Notocactus ottonis f. elegans in Repert. Pl. Succ. 14: 11. 1990
is new combination for Notocactus ottonis var. elegans in Arch. Jard. Bot. Rio de Janeiro 9: 172. 1950