Plants unbranched (very rarely branched), appearing pure white or slightly yellowish, smooth, and shiny in general aspect. Stems flat-topped, disk-shaped, short cylindric, or cylindric, 2-5 cm diam. Spines (40-)50-90 per areole, in more than 3 superimposed series; mature lateral spine clusters uniformly white to creamy yellow, 2-2.5(-4) mm diam.; longest intact spines 4.5-7 mm; worn spines 0.1-2 mm. Flowers conspicuously exserted beyond longer spines at stem apex, 1-1.7 × 1-1.7 cm; inner tepals 13-21 per flower, 5-6(-9) × 1.5-2.3(-3) mm; stamens 20-40. 2n = 22.
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