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DescriptionAnnual herbs. Stems caulescent, erect or decumbent, puberulous. Leaves simple, alternate, usually petiolate, lamina elliptic, pubescent, margin serrate, apex acute, base attenuate, chartaceous. Capitulescences axillary, in clusters. Capitula discoid, homogamous, hemispherical, sessile, florets bisexual and fertile. Involucre imbricate. Florets 50–70; corollas purple to white, actinomorphic, glandular, corolla lobes 3–4. Anthers 3 or 4, syngenesious. Styles purple, 2-branched, inner surface covered with stigmatic papillae, outer surface covered with sweeping hairs reaching to below style bifurcation. Achenes turbinate, 3–4-angular, usually 3–5-ribbed, carpopodium present. Pappus coroniform, thick, in 1 series, persistent. Pollen lophate, 3-porate, without micropuncta. One species is recognized in Thailand.