Erect, annual, usually divaricately branched, 10-70 cm tall herb, branches on the lower side with retrorse, bristle-like hairs. Basal leaves petiolate, oblong-obovate, 3 – 12 x 1 – 3 cm, sinuate-dentate; upper stem leaves sessile petiolate, entire to toothed or sinuately toothed, narrowly obovate to oblong-lanceolate, uppermost leaves amplexicaul, sagittatge. Capitula 5 – 7 mm across, on small, thick, clavate, usually retrorsely sharp bristly peduncles, sometimes bristles absent. Involucre 4 – 5 mm long, accrescent in fruit, up to 10 mm long, short, retrorse spiny outside, occasionally smooth or with scales. Cypselas reddish-brown, inconspicuously curved, c. 5 x 1.5 – 1.8 mm, sulcate, laterally compressed, ribbed, ribs ±scaly-tuberculate, shortly beaked.