Annual herb. Stems erect or ascending, branched above, ribbed, glabrous or with cobwebby hairs, 5-45-(100) cm tall. Lvs with short eglandular hairs, petiolate or cuneate to base. Rosette and lower stem lvs linear-oblanceolate, shallowly pinnatifid or dentate, acute, 20-125 × 4-25 mm. Upper lvs linear- lanceolate, entire or toothed, the uppermost filiform. Capitula on curved thickened peduncles, the axillary peduncles overtopping the terminal capitula. Involucre 10-15 mm long; bracts with cobwebby tomentum, filiform with thickened midrib; outer bracts spreading or erecto-patent, = or > inner; inner bracts erect. Corolla usually yellow, sometimes purple at base, rarely purple, c. 11/2× length of involucre; tube < ligule. Achenes narrowly obconic, 4-angled, dark, 1-1.5 mm long, flat at apex; outer row of achenes pubescent with pappus of only short hairs c. 0.3 mm long; inner achenes glabrous with pappus of short hairs and (2)-4 long bristles 3-4 mm long.