Mammillaria backebergiana subsp. ernestii (Fittkau) D.R. Hunt, Mammillaria Postscripts 6: 8. 1997 sec. Hunt 2016
- ≡Mammillaria ernestii Fittkau in Cact. Suc. Mex. 16: 36. 1971 syn. sec. Guzmán & al. 2003
- =Mammillaria backebergiana var. ernestii (Fittkau) Glass & R.A. Foster in Cact. Succ. J. (Los Angeles) 51: 126. 1979 syn. sec. Guzmán & al. 2003
- =Mammillaria isotensis Repp., Gatt. Mammillaria: 78. 1987 syn. sec. Guzmán & al. 2003