Shrubs [to small trees], with basal branches sometimes rooting to form thickets. Stems green with red around young areoles, aging gray-green with faint waxy chevrons; ribs somewhat rounded, margins relatively flat; areoles 1-1.5 cm apart on rib crest, shield-shaped, on proximal stems 1 cm wide, those on distal stems closer together, circular; young hairs whitish gray, short. Spines strongly dimorphic, those on proximal stems usually 7-10 per areole, rose-red, aging gray, stout, usually 5-7 mm, to less than 30 mm, weakly differentiated as central and radial spines, those on distal stems usually more than 15 per areole, gray to blackish (rarely aging copper-brown), thin, flattened, twisted, to 7.5 cm; bristles 4-10 cm. Flowers lateral on stems, often several per areole, on specialized bristle-forming or transition areoles, short funnelform, 3-4.5 × 2-3 cm; flower tube thin walled, very narrow, less than 1.5 cm; nectar chamber open; scales rose with green margins; tepals spreading, reflexed by morning; outer tepals somewhat fimbriate, minutely papillate; inner tepals 25, with pink-orange center, 11-16 mm, apex acute; stamens 100, white, turning pink by next morning, to 2 cm; anthers cream; ovary small, tubercles and spines absent; styles white, short, narrow; stigma lobes erect, relatively short. Fruits candy-apple red, when immature greenish, ovoid to subspheric, 25-40 mm. Seeds helmet-shaped, often with a prominent raphe. 2n = 22.