Coryphantha radians var. impexicoma (Lem. ex C.F.Först.) Backeb. & F.M.Knuth, Kaktus-ABC: 370. 1936 ["1935"] Coryphantha radians var. impexicoma (Lem. ex C.F.Först.) Backeb. & F.M.Knuth, Kaktus-ABC: 370. 1936 ["1935"]Taxon for this nameCoryphantha radians var. impexicoma (Lem. ex C.F.Först.) Backeb. & F.M.Knuth