Annual to 80 cm high; stems with discontinuous wings to c. 5 mm wide and spinose lobes to 5 mm wide, cobwebbed. Basal leaves in a sparse rosette, oblanceolate in outline, 5–20 cm long, 2–8 cm wide, deeply pinnatisect, margins spiny, upper surface green and pubescent, lower surface white-cobwebbed; cauline leaves similar but smaller, stem-clasping. Inflorescence of 1–3 capitula in terminal clusters; capitula cylindric, erect, c. 10 mm diam.; peduncles 3–40 mm long, terete; involucral bracts linear-lanceolate, to 20 mm long, erect; dorsal surface of intermediate involucral bracts covered with minute antrorse hairs; inner bracts slightly shorter than florets. Corolla 10–17 mm long, pinkish-purple. Cypselas 4–5 mm long; pappus bristles subequal, 10–14 mm long. Flowers mainly spring and summer.