Subspecies, varieties, forms and cultivars of plants belonging to the Mammillaria standleyi group

• Mammillaria floresii Fritz Schwarz: usually solitary. Central spines (2-)4, reddish 5-9 mm long. Radials few to 16, 4-8 mm long. Flowers purplish red to 12 mm long. Distribution: San Bernardo, Sonora.
• Mammillaria lindsayi R.T.Craig: forms clumps up to 1 m wide, has white axillary wool and bristles. Radial spines 10-14 white, centrals 2-4 , straight, brown to black, flowers greenish yellow. Distribution: Chihuahua and Sinaloa, Mexico.
• Mammillaria lindsayi var. cobrensis Repp.: is distinguishable from the type for the stem that is always solitary with a very woolly apex. The stem is dark green and it lacks of bristles in the woolly tubercles axil. Distribution: Barranca del Cobre, Chihuahua, Mexico.
• Mammillaria lindsayi var. rubriflora Hils: as the name implies it has reddish flower.
• Mammillaria miegiana W.H.Earle: mostly solitary with stems, densely covered by spines appearing white and producing large, dark reddish-pink flowers with scarlet midveins. Distribution: Northem Sonora.
• Mammillaria standleyi (Britton & Rose) Orcutt: very variable, with white radial spine, brownish centrals and white wool between the tubercles. Flowers purplish up to 12 mm long. Distribution: Chihuahua, Sinaloa, and Sonora.