Herbs, monocarpic, 20-50 cm tall, throughout with fulvous or yellowish, firm spines. Taproot terete, attenuate toward base, ca. 20 × 0.5-1.5 cm. Stem erect, terete, 5-10 mm in diam. near base, basally with smooth persistent leaf bases. Basal leaves: petiole 3-8 cm, narrowly winged; blade green on both surfaces, oblong-lanceolate, oblanceolate, or rarely narrowly ovate, 5-20 × 0.7-4.2 cm, both surfaces with fulvous or yellowish, pale, spreading spines, midvein ridged abaxially, lateral veins obscure on both surfaces, base narrowly cuneate, decurrent into petiole, margin entire or undulate, rarely irregularly crenate or shallowly lobed, apex acute or obtuse. Lower cauline leaves few, shortly petiolate, like basal leaves, decreasing in size upward on stem and merging with bracts; uppermost leaves sessile. Inflorescence a simple raceme with up to 14 flowers, sometimes with additional, solitary, scapose flowers in axils of basal leaves. Pedicel 2-5 cm. Flower buds nodding, suborbicular or ovoid, ca. 1 cm in diam. Sepals oblong-ovate, adaxially spiny-hairy. Petals 5-8, blue or blue-purple, sometimes wine-purple or reddish, obovate-oblong, 2-3 × 1-2 cm, glabrous. Filaments of same color as petals, often rather darker, ca. 1 cm; anthers yellow or cream, oblong, 1.25-1.5 mm. Ovary ovoid, 5-8 mm, densely spiny-hairy; styles conical, 2-4 mm, ridged, glabrous, protruding from boss of stamens; stigmas whitish, oblong, 1-2 mm. Capsule ovoid or narrowly ovoid, 0.5-15 × 0.4-1 cm, with dense, spreading bristles, 4-6-valvate to 1/3 its length from apex; persistent styles 7-10 mm. Seeds oblong, 1-2 mm, seed coat clathrate-tessellate. Fl. May-Aug.
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