Herbs perennial, rhizomatous. Leaves mostly on proximal 1/2 of stem, near middle, or distal; leaf blade palmately divided; primary lobes 1- to many lobulate. Petals of same color as sepals, not black-brown. Staminodes of same color as sepals, not black-brown, distinctly differentiated into a claw and an expanded, broad limb; limb adaxially yellow or white barbate. Carpels 3(--5). Seeds mostly transversely squamulose winged, rarely narrowly winged only along angles.

About 170 species: mainly in the N hemisphere, a few species in Africa; 104 species (95 endemic) in China.