Annual, biennial or perennial herbs; stems erect with spiny wings. Leaves basal and cauline, alternate, usually decurrent, toothed to deeply pinnatisect, teeth and lobes spine-tipped. Capitula hemispherical to cylindric, terminal or axillary, in dense clusters or solitary, sessile or pedunculate; involucral bracts in many series, unequal, imbricate, rigid, spinose; receptacle flat or convex, densely hairy. Florets bisexual, tubular, more or less equal, purple to white; corolla deeply 5-lobed, sometimes c. 2-lipped; anthers sagittate at base, with acute appendages at apex; style shortly bilobed, with linear flattened branches, apices obtuse and minutely papillose. Cypselas ovoid to obovoid, somewhat compressed or angled, striate, glabrous; pappus of several series of barbellate bristles, connate at base into a ring and deciduous as a unit.
