Thelocactus bicolor (Galeotti ex Pfeiff.) Britton & Rose in Bull. Torrey Bot. Club 49: 251. 1922
Thelocactus bicolor in Bull. Torrey Bot. Club 49: 251. 1922
is new combination for Echinocactus bicolor, Abbild. Beschr. Cact. 2: t. 25. 1848
Thelocactus bicolor in Bull. Torrey Bot. Club 49: 251. 1922