This choice, slow-growing, robust-globular cactus has been considered by some to be a subspecies of T. bicolor. It looks more like a green form of T. hexaedrophorus, with which it shares usually solitary stems with buxom, rounded tubercles armed with bold clusters of claw-like spines. These are a bit more slender in T. heterochromus, and, as the name implies, are often shaded different colors from white to yellow, or red. The flowers are a gorgeous magenta, usually with red at the base. The species is native to the states of Chihuahua, Durango, and Zacatecas, Mexico. HBG 98575. $7.
Published in the Cactus and Succulent Journal, Vol. 81 (2), March - April, 2009