Annual, erect, herbs with glabrous or hairy stem. Leaves opposite, shortly petiolate or sessile, lanceolate to broadly ovate, glabrous or hairy, entire or serrate. Capitula radiate or discoid. Involucre hemispherical. Phyllaries biseriate, subequal to gradate, herbaceous to membranaceous or distally scarious. Receptacle conical, paleate, paleae persistent or deciduous, scarious, broadly elliptic to obovate, weakly 3–lobed, outer ones connate at base with a single phyllary, enclosing the ray cypselas and dispersing as a single unit wih the cypsela. Ray florets white or pinkish, female, fertile, corolla tube pilose, ligule quadrate–obovate to oblong, lobes 0–3. Disc florets yellow, bisexual, fertile; corolla tube shorter than cylindric limb, pilose, limb 5–lobed, lobes deltate. Anthers yellow. Style branchs acute at apex. Cypselas obconical, blackish, ray cypselas flattened, pappus of small awns or absent; disc cypselas angular, pappus of 8–20, deeply fimbriate, lanceolate or sometimes aristate scales.
A small genus of 16 species, distributed in North and South America; introduced in Europe, Africa, Asia, and Australia. In Pakistan it is represented by the following species..