Coryphantha retusa (Pfeiff.) Britton & Rose, Cactaceae 4: 38. 1923 Coryphantha retusa (Pfeiff.) Britton & Rose, Cactaceae 4: 38. 1923is new combination for Mammillaria retusa Pfeiff. in Allg. Gartenzeitung 5: 369. 1837Taxon for this nameCoryphantha retusa (Pfeiff.) Britton & Rose, Cactaceae 4: 38. 1923