Thelocactus bicolor subsp. bicolor sec. Parfitt & Gibson 20031
≡Thelocactus bicolor var. bicolor syn. sec. ???
1.Parfitt, B.D. & Gibson, A.C. 2003: Cactaceae. – In: Flora of North America Editorial Committee, Flora of North America 4. Magnoliophyta: Caryophyllidae, part 1