Coryphantha radians var. echinus (Engelm.) Y.Itô, Cacti, ed. 2: 115. 1952 Coryphantha radians var. echinus (Engelm.) Y.Itô, Cacti, ed. 2: 115. 1952is new combination for Mammillaria echinus Engelm. in Proc. Amer. Acad. Arts 3: 267. 1856Taxon for this nameCoryphantha radians var. echinus (Engelm.) Y.Itô