Annual her (ours). Leaves mostly alternate but sometimes opposite. Inflorescence a lax corymb or a few capitula on long peduncles or capitula solitary. Capitula heterogamous, radiate; ray-florets sterile; disk-florets bisexual and fertile. Involucre hemispheric or subspherical. Phyllaries in 2-6 rows. Receptacular scales convex. Ray-florets with a long (c. 1 cm), yellow, 2-3-dentate ligule. Disk-florets cylindric, 5-lobed. Anthers with a terminal appendage. Achenes flattened, with a broad irregular winged margin. Pappus of 2 awns. Worldwide: c. 300 species in warm regions of America; ours a tropical weed Zimbabwe: 1 taxon. |
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