Ritterocactus mammulosus subsp. eugeniae (Vliet) Doweld in Sukkulenty 2(2): 22. 1999 Ritterocactus mammulosus subsp. eugeniae (Vliet) Doweld in Sukkulenty 2(2): 22. 1999is new combination for Notocactus eugeniae Vliet in Succulenta (Netherlands) 55(2): 24. 1976Taxon for this nameRitterocactus mammulosus subsp. eugeniae (Vliet) Doweld