Stem usually unbranched, depressed-spheric, or spheric to elongate-cylindric, 3-7(-14) × 4-9(-11) cm; ribs 13-15, tubercles usually evident on ribs. Spines densely covering stem; radial spines (5-)7-12 per areole, white except for abaxial 2 that are usually purplish pink, 0.6-27 mm; central spines 4(-5) per areole, terete to angled; abaxial central spine 1 per areole, purplish pink or reddish brown, somewhat angled, hooked, 16-45(-55) × 0.5-1 mm; lateral central spines 2 per areole, directed toward stem apex, purplish pink to white, 14-45 × 0.5-1 mm; adaxial central spine white, usually flat, ribbonlike or dagger-shaped, 17-65(-70) × 1.5-2(-3) mm. Flowers funnelform to campanulate, (1.5-)2.2-3.2 × 1.5-3.5 cm; outer tepals with greenish or reddish midstripes and yellow margins, oblanceolate, to 24 × 5 mm; inner tepals yellow, oblanceolate, to 30 × 6 mm; filaments yellow; anthers yellow; ovary minutely papillate, appearing smooth. Fruits irregularly dehiscent, green to tan, often reddish at maturity, ovoid, 10-25 × 6-15 mm, dry; scales few, scarious margined, minutely toothed, membranous-fringed. Seeds black, 2 × 2 mm, shiny; testa with rounded papillae.
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