Mammillaria discolor Haw.

Solitary, body globular to 8 cm wide. Tubercles obscured, conical. Axils bare. Central spines 6-8, to 10 mm, yellowish or black, needle-like. Radial spines 16-20, to 10 mm long, whitish or yellowish-brown. Flowers pale yellow or pinkish with a pinkish central stripe, 2 cm long, 1.5 cm wide. Fruit red.

C Mexico

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.

kingdom Plantae
phylum   Tracheophyta
class    Magnoliopsida
superorder     Caryophyllanae
order      Caryophyllales
family       Cactaceae
genus        Mammillaria Haw.