Mammillaria zacatecasensis Shurly

Solitary, body globular or elongate, to 6 cm wide and to 15 cm high without milky sap. Tubercles prominent, ovoid. Axils bare. Central spines 3-4, upper 2(-3) 10 mm long straight, lower 15 mm long, tips hooked. Radial spines 20-25, 3-5 mm long, pale yellowish, fine. Flowers white or pale pink with pink central stripe, to 1.8 cm long and 1.5 cm wide. Fruit red.

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.