Body solitary, compressed spherical to clindrical. Ribs 20-40 or so, areoles close-set. Central spines 1-4, radials 6-9. Flowers yellow. Fruit pink.

C Mexico

 

F. pottsii (Salm-Dyck) Werderm. from NW Mexico has 1 central spine to 7.5 cm long that often curved upwards and F. pottsii var. alamosanus (Britton & Rose) G. Unger has narrow-edged ribs and densely distributed yellow radial spines.

Source: Thompson, A, ; Forbes, S.; Spencer, R. (1997). Cactaceae. In: Spencer, R.. Horticultural Flora of South-eastern Australia. Volume 2. Flowering plants. Dicotyledons. Part 1. The identification of garden and cultivated plants. University of New South Wales Press.