Description: Annual or occasionally perennial herbs, usually very glandular hairy and heavy scented.
Leaves opposite or alternate, entire to remotely toothed.
Heads sessile, or on short peduncles, ± racemose, usually many-flowered; heads cup-shaped; involucral bracts completely enclosing the ray achenes, 1-seriate and as many as ray florets; receptacle with 1 or 2 series of scales between ray and disc florets, forming a ± united often persistent cup. Ray florets 5–12, ligulate, in 1 row, fertile. Disc florets tubular, fertile or sterile.
Ray achenes usually laterally compressed, with flat sides, narrowed to base, longitudinally striate; pappus usually absent in ray achenes, sometimes present in disc achenes.
Distribution and occurrence: World c. 18 species, Pacific, North & South America. Australia: 1 species (naturalized).
Text by L. Murray Taxon concept:
One species in NSW: Madia sativa |
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