Echinomastus kakui Backeb., Descr. Cact. Nov. 3: 6. 1963 Echinomastus kakui Backeb., Descr. Cact. Nov. 3: 6. 1963Taxon for this nameEchinomastus kakui Backeb., Descr. Cact. Nov. 3: 6. 1963