Ancistrocactus megarhizus (Rose) Britton & Rose, Cactaceae 4: 4. 1923
Ancistrocactus megarhizus, Cactaceae 4: 4. 1923
is new combination for Echinocactus megarrhizus in Contr. U.S. Natl. Herb. 12: 290. 1909
Ancistrocactus megarhizus, Cactaceae 4: 4. 1923