Erect branching subshrubs or herbs, rarely scandent. Leaves alternate, pubescent or glabrous. Heads discoid, in corymbs or sometimes panicles, florets pink, purple or blue. Involucre campanulate or subglobose, bracts imbricate, in many series, outer series smaller, sometimes spreading, acute, acuminate, awn-tipped, or obtuse. Receptacle alveolate denticulate, rarely with crisped hairs, florets all tubular, fertile. Corolla regular, 5-cleft. Anthers obtuse or sagittate at base, auricles connate. Style arms linear, subacute, puberulent. Achenes 8 to 10-ribbed, truncate, callose at base, glabrous or pubescent. Pappus bristles numerous, 1- or 2-seriate, inner row capillary, deciduous or persistent; outer row very short.
About 1,000 species in warmer regions of America, Asia and Africa; in Taiwan, five species, one of which is represented by two varieties.