Solitary, body shortly cylindrical to 15 cm high, crown white. Axils white woolly. 2(-4) brownish-tipped white central spines 2-5 mm long, 15-20 white radial spines 2-3 mm long. Flowers in a ring around crown, carmine, to 8 mm long. Fruit pink to red. [M. fuauxiana Backeb.]
The form with longer central spines was recognised by Backeberg as M. fuauaxiana Backeb. The form is of particular interest as the only cactus named for an Australian — the doyen of Australian collectors, Lex Fuaux.
Source: (1997). Cactaceae. In: . 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.