Variation
var. townsendianus
This form of the plant is found from Mexico to South of California and forms a solitary habit up to 500 mm (20 in) tall by 300 mm (12 in) in diameter with a slightly glaucous body.  

The areoles have stiff hooked red spines and the pale yellow to a deep orange flower has darker orange stripes at the centre of the tepals. They appear from late summer to early autumn, staying in bloom several weeks followed by yellowish green scaly fruit. It is a slow growing cactus that does well under cultivation and can tolerate sporadic light frost.