First description by Quehl; Monatschrift für kakteenkunde 17 (4) : 59 - 60, (1907).

Body: Solitary at first, later clumping or dividing dichotomously, slightly sunken apex, 7 - 8 cm high and to 6 cm in diameter.
Roots: Fibrous.
Sap: With latex.
Tubercule: Pyramidal, four - angled, rounded dorsally, 8 mm long and 5 mm wide at base.
Axil: With white wool and a few white bristles.
Radial spine: 4 - 8, mostly 3 - 10 mm long, straight, stiff, smooth, the lowest and the uppermost the longest, acicular, ascending, white with red or brown tip.
Central spine: Absent.
Flower: Funnelform, 15 mm long and 10 mm in diameter, yellowish white with reddish-brown tips.
Fruit: Club-shaped, carmine, 15 mm long and 5 - 6 mm wide. Selfsterile.
Seed: Dull brown, curved pyriform, 0,9 mm long and 0,6 mm wide. Hilum subbasal.
Habitat Substrate: In rocky ground with lots of humus.
Geographic Distribution: Mexico, Morelos, near San Rafael. Altitude 1100 - 1300 m.
Comments: Belongs in the polyedrae group and is very related to M. beiselli and M. tropica.
Bibliography: AfM - LBS Lieferung 09/98 Linzen.