Erect, slender, branching annual 30–40 cm high; stems sparsely appressed-pilose. Leaves trifid, with central lobe greatly exceeding length of 2 basal, lateral lobes, giving the appearance of three simple leaves, apparently 1-veined; lobes linear to narrowly lanceolate, 15–65 mm long, 2–4 mm wide, entire or with occasional small tooth; adaxial surface strigose; abaxial surface with hairs restricted to margins and midrib; hairs 0.2–0.3 mm long, appressed, 2-celled with basal cell swollen, seated on cluster of tiny epidermal cells, upper cell conical. Capitula sparse, in open, lax dichasial clusters, on slender peduncles to 35 mm long; involucre campanulate-hemispherical, 3 mm long, 3–5 mm wide. Disc florets 10–15; corolla yellow. Achenes obovate, 2.8–3 mm long, 1.7–2 mm wide, dark brown to black; abaxial surface convex with minute hairs apically, otherwise smooth; adaxial surface concave, flat, with weak central keel, minutely pilose throughout, occasionally papillose; margin a thickened revolute wing, usually crenate, often with apical points touching on adaxial surface. Pappus diminutive or absent, if present coroniform, lacking awns.
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