Annuals, 10–100 cm. Stems simple or often branched from base, forming rounded bushy plants, gray-tomentose. Leaves gray-tomentose and scabrous to short-bristly; basal and proximal cauline petiolate or tapered to base, usually absent at anthesis, blades 5–15 cm, margins pinnately lobed or dissected; cauline long-decurrent, blades linear to oblong, 1–10 cm, entire. Heads disciform, borne singly or in open leafy arrays, long-pedunculate. Involucres ovoid, 13–17 mm, loosely cobwebby-tomentose or becoming glabrous. Principal phyllaries: bodies pale green, ovate, appendages stramineous to brown, each with palmately radiating cluster of spines, and stout central spine 10–25 mm. Inner phyllaries: appendages scarious, obtuse or abruptly spine tipped. Florets many; corollas yellow, all ± equal, 13–20 mm; sterile florets slender, inconspicuous. Cypselae dimorphic, 2–3 mm, glabrous, outer dark brown, without pappi, inner white or light brown, mottled; pappi of many white, unequal bristles 2–4 mm, fine. 2n = 16.
