Ferocactus macrodiscus (Mart.) Britton & Rose Ferocactus macrodiscus (Mart.) Britton & Rose, Cactaceae (Britton & Rose) 3: 139. 1922 sec. Guzmán & al. 2003≡Echinocactus macrodiscus Mart. in Nova Acta Acad. Caes. Leop.-Carol. German. Nat. Cur. 16: 341. 1832 syn. sec. Guzmán & al. 2003