Ritterocactus allosiphon (Marchesi) Doweld in Sukkulenty 2(2): 22. 1999 Ritterocactus allosiphon (Marchesi) Doweld in Sukkulenty 2(2): 22. 1999is new combination for Notocactus allosiphon Marchesi in Bol. Soc. Argent. Bot. 14: 246, f. 1972Taxon for this nameRitterocactus allosiphon (Marchesi) Doweld