Heliantheae

Annual or perennial herbs, shrubs, trees, or vines without latex; leaves alternate or opposite; heads radiate or discoid (rarely disciform), size varies; involucre cylindric to hemispheric, bracts in 1–7 series, often foliaceous; receptacle paleate (rarely naked) with paleae enfolding achenes and usually persistent; ray florets if present pistillate or sterile, corollas usually yellowish, sometimes white (rarely orange to reddish), strap-shaped with usually three lobes; disc corollas yellow with five lobes of usually equal (rarely unequal) size; anther apical appendage usually ovate, thecae usually blackened, usu- ally without spurs (ecalcarate), often sagittate (rarely with short tails = caudate); pollen echinate and spherical; styles slender, branches with separate or fused stigmatic lines, apices often terminated by tuft of hairs, the style glabrous below the bifurcation, at maturity style branches recurv- ing; achenes compressed (rarely obcompressed), achene walls smooth or striate, with phytomelanin layer; pappus of awns or scales, sometimes coroniform (rarely absent).

Diagnostic Features

Combination of paleate receptacles, with paleae enfolding ovaries; usually blackened anthers; style apices terminated by tuft of papillae; achenes black- ened, flattened; and pappus usually of awns or scales.

Geographic distribution

Mainly warm temperate and tropical New World.