Mammillaria missouriensis var. caespitosa (Engelm.) S.Watson in Smithsonian Misc. Collect. 258: 403. 1878
Mammillaria missouriensis var. caespitosa in Smithsonian Misc. Collect. 258: 403. 1878
is new combination for Mammillaria similis var. caespitosa in Boston J. Nat. Hist. 6(2): 200. 1850