Mammillaria deherdtiana Farwig

Solitary, body spherical to 5 cm wide, crown depressed or flat, tap root absent. Tubercles prominent. Axils slightly woolly. Central spines (0-)1-6, 3-7 mm long, dark reddish brown. Radial spines 33-36, 3-6 mm long, yellowish or whitish. Flowers pinkish with darker central stripe, 5 cm wide and 2 cm long. Fruit pale green.

SW Mexico

Distinguished from M. dodsonii Bravo [M. deherdtiana var. dodsonii Bravo] by lower tubercle spiral count (5-8 cf. 8-13) and spination-central spines 3-5, 10-20 mm long brownish, radial spines 20-21, 10-18 mm long, whitish; also flowers a deeper rose-violet.

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.