Description: Annual to perennial herbs with taproot or roots creeping.
Leaves basal and cauline, alternate, pinnatifid or toothed, cauline leaves stem-clasping.
Heads several, in a loosely branched inflorescence, cylindrical becoming conical; involucral bracts 3-seriate, unequal, inner longer and more membranous, reflexed in fruit; receptacle flat, naked or with small scales or fine hairs, pitted. Florets all ligulate, bisexual, fertile; corolla yellow, tube pubescent above. Anthers sagittate at base, orange, apical appendage triangular and dark. Style branches linear, terete, papillose.
Achenes ± flattened, 3–5 ribs on each face, winged or not, beak absent; pappus in many rows, of free barbellate bristles and persistent cottony hairs.
Distribution and occurrence: World: 55 species, cosmopolitan. Australia: 5 species (4 species naturalized), all States.
Text by L. Murray
| ||Key to the species|| |
|1||Leaves stiff and more or less leathery; achenes with ribs and scabrous on the margins, otherwise smooth||2|
|Leaves soft, thin; achenes wrinkled throughout||Sonchus oleraceus|
|2||Leaves with margins spinose; basal leaves pinnatifid||Sonchus asper|
|Leaves with margins toothed; basal leaves sinuate-pinnatifid|
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