STEMS: 2.2-6 cm long, 2.7-4.5 cm in diameter. SPINES: central spines 0; peripheral (intermediate) spines 1, 0.8-2.1 cm long, 0.7-1.5 mm wide at the base; radial spines 3-6, 2-9 mm long, 0.5-1 mm wide. NOTES: See also parent taxon. Desertscrub: endemic to Navajo co.; 1500 m (5100 ft); Apr-May. REFERENCES: Heil, Kenneth D., and Mark J. Porter. 2001. Cactaceae. J. Ariz. - Nev. Acad. Sci. Volume 33(1)