Mammillaria kraehenbuehlii (Krainz) Krainz

Clustering and mounding, body prominently globular, to 3.5 cm wide. Tubercles prominent, angular. Axils bare. Central spine solitary and exceeding radials or absent. Radial spines 18-24, 3-8 mm long, whitish, tips brown. Flowers carmine, 18 mm long. Fruit dark carmine.

S 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.