Annuals, 5–45 cm; taproots 2–5+ cm. Stems 1–15+, often branched at base or throughout, moderately stout to stout, not wiry, moderately hairy (hairs antrorsely appressed). Leaves: basal often withering by flowering, blades 20–60 × 10–25 mm, pinnatifid to 2-pinnatifid; cauline evenly spaced, blades obovate to oblanceolate (proximal), oblong to linear (distal 2 / 3 +), 4–10(–20) × 1–3 mm, markedly reduced distally, margins evenly serrate to serrulate, teeth 3–6 per side, each tipped with prominent white bristle 1.5–2.5 mm, faces moderately hairy (hairs antrorsely appressed). Peduncles moderately hairy (hairs fine, antrorsely appressed, straight to wavy); usually ebracteate. Involucres hemispheric, 0.6–0.8 × 0.8–1.3 cm. Phyllaries in 4–5 series, linear to narrowly spatulate, 2–7 mm, apices usually acuminate, sometimes rounded, tipped by white bristle, faces hairy (moderately antrorsely appressed hairs), sparsely and minutely stipitate-glandular distally. Ray florets 12–26; corollas yellow, tubes 2.2–3 mm, laminae 6–9.5 × 1–2.5 mm. Disc florets 50–100+; corollas 4–5 mm. Cypselae narrowly obovoid to oblanceoloid, 1.5–2.8 mm, nerves 24–28, faces sparsely whitish hairy; pappi whitish to tawny, 4–5 mm, bristles progressively longer adaxially. 2n = 4, 6, 8.
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