Description: Annual or perennial herbs, rarely somewhat woody.
Leaves opposite, simple or 1–3 times pinnately dissected into narrow lobes.
Heads terminal, solitary or in loose cymes, pedunculate; receptacle flat, with scales; involucral bracts fused at the base, 2 seriate, unequal, outer usually herbaceous or a little fleshy, inner membranous and subtending the ray florets. Ray florets in 1 row, ligulate, sterile. Disc florets tubular, bisexual, 5-toothed, fertile. Anthers auriculate at the base. Style branches slender, usually apiculate with short awnlike appendage.
Achenes usually fusiform, sometimes linear, with a conspicuous beak; pappus absent or 2–8 awns, usually with retrorse barbs, sometimes antrorse barbs or hispid.
Distribution and occurrence: World: 25 species, tropical & subtropical America & West Indies. Australia: 1 species (naturalized).
Text by L. Murray Taxon concept:
One species in NSW: Cosmos bipinnatus |
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