Description: Large, erect, spiny, robust annual or biennial herbs.
Leaves basal and cauline, alternate, margins toothed to pinnatisect, with thickened spiny margins, sessile and auriculate to amplexicaul.
Heads solitary, terminal, ovoid; involucral bracts many-seriate, unequal, leathery, spine-tipped; the outer and middle with an apical, toothed or scale appendage terminating (at least in the middle) in a long spine; receptacle flat, densely hairy. Florets all tubular, bisexual, fertile; corolla deeply 5-toothed, purple. Anthers sagittate at base, apex acute. Style branches linear, erect, appressed.
Achenes compressed, ovoid to oblong, smooth; pappus of numerous, several-seriate, barbellate bristles united in a ring at the base, innermost short and fine.
Distribution and occurrence: World: 2 species, Europe & northern Africa. Australia: 1 species (naturalized).
Text by L. Murray
|One species in NSW: Silybum marianum|