Mammillaria fittkaui Glass & R.A.Foster in Cact. Succ. J. (Los Angeles) 43: 115–117. 1971 sec. Hunt 2016
- ≡Escobariopsis fittkaui (Glass & R.A.Foster) Doweld in Sukkulenty 3: 40. 2000 syn. sec. Kew WCVP (2019)
- =Mammillaria variabilis Repp. in Kakteen And. Sukk. 36: 207. 1985 syn. sec. Hunt 2016
