Anhalonium williamsii (Lem. ex Salm-Dyck) C.F.Först., Handb. Cacteenk., ed. 2: 233. 1885
Anhalonium williamsii, Handb. Cacteenk., ed. 2: 233. 1885
is new combination for Echinocactus williamsii in Allg. Gartenzeitung 13: 385-386. 1845
Anhalonium williamsii, Handb. Cacteenk., ed. 2: 233. 1885