Mammillaria caput-medusae Otto ex Pfeiff., Enum. Diagn. Cact.: 22. 1837
Mammillaria caput-medusae, Enum. Diagn. Cact.: 22. 1837
is basionym for Neomammillaria sempervivi var. caput-medusae, Cactaceae: 615. 1981
is basionym for Mammillaria sempervivi var. caput-medusae, Cactaceae 5: 3160. 1961