Description: Annual or perennial herbs.
Leaves cauline, opposite to alternate, petiolate, simple.
Heads long-pedunculate, terminal, solitary or in loose cymes; heads hemispherical, becoming reflexed in fruit; involucral bracts 2- or 3-seriate, numerous, subequal, herbaceous; receptacle convex, pitted, with non-persistent scales. Ray florets in 1 row, female, fertile or sterile, ligulate. Disc florets bisexual, fertile, 5-toothed; anthers obtuse at the base, with a narrow acute appendage at the apex; style branches linear, with shortly hairy subulate terminal appendages.
Achenes compressed, oblong to obovate, often winged; pappus of 2 awns or absent.
Distribution and occurrence: World: c. 150 species, North & South America. Australia: 1 species (naturalized).
Text by L. Murray