Annuals, 5–40 cm; taprooted. Leaves basal; petiolate; blades linear to oblanceolate, 3–25 cm, margins entire, dentate, or pinnately lobed (lobes slender, tapering), apices acute to acuminate, faces ± scurfy-puberulent. Peduncles erect or curved-ascending, ebracteate. Involucres globose to fusiform in fruit, 7–16 mm. Phyllaries: apices erect, acute to acuminate; outer deltate, glabrous or lightly scurfy-puberulent; inner lanceolate, faces often lightly black-villous on margins (midveins often purple-lined, thickened). Florets 5–200; corollas yellow or white, equaling or surpassing phyllaries by 1–3 mm. Cypselae columnar or obconic, 3–10 mm; pappi of (0–)1–5, white to yellow, brown, or blackish, aristate scales 0.5–7 mm (± arcuate, usually distinctly involute, except subsp. tenella, often abaxially villous, midveins usually tapering distally from thick bases, except subsp. tenella, widths less than 1/5 bodies), aristae (white or straw-colored, ± stout) barbellate. 2n = 18.
