Annual herb 20-70 cm high; stems with spreading or ascending hairs. Leaves opposite on the lower part of the plant, alternate above, sessile, (narrowly) elliptic or narrowly ovate, 3-10 cm long, 1-4 cm wide, cuneate or attenuate at the base, incised to almost pinnatilobed with coarsely crenate-serrate lobes or coarsely serrate with apiculate teeth, apex obtuse and apiculate, thinly pubescent on main veins beneath and less densely so above, glabrescent. Capitula rather numerous, clustered in apical and upper axillary compound corymbiform cymes; stalks of individual capitula with ascending and spreading hairs; involucres campanulate, 5-8 mm long, 4.5-6 mm in diameter; phyllaries 3-4-seriate, (narrowly) ovate, acute to acuminate-apiculate, the innermost obtuse and shortly apiculate-pungent, long-pilose in upper part, darker green and slightly hairy in upper part below apex and with pallid membranous margins, 6-6.5 mm long. Florets 40-50 per capitulum; corolla violet or mauve, 4.5-5.5 mm long, lobes 1.5-2 mm long. Achenes 1.3-1.5 mm long, with 5 rounded ribs, glabrous; pappus tawny, 1.8-2.5 mm long, caducous.
