Annual or perennial herbs. Leaves
opposite. Capitula solitary on long peduncles, radiate,
heterogamous. Ray florets female, fertile; disk bisexual and
fertile. Involucre ± hemispheric. Phyllaries in 2 series,
the outer shorter than or equal to the inner. Rays present,
3-lobed or dentate; disk florets cylindric, 5-lobed. Receptacular
scales linear, ± keeled. Achenes silky-villous. Pappus
of numerous densely plumose bristles. Worldwide: 30 species, American, mostly Mexico Caprivi: 1 taxon. |
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