Herbs , perennial, from ca. 1cm thick rhizomes formed of several subglobose segments (tubers). Leaves basal, petiolate. Leaf blade deeply, palmately divided or 3--5-foliolate; leaflets ovate, unlobed to 3-lobed, margins sharply cleft, irregularly dentate. Inflorescences terminal, flowers solitary; involucres present, involucral bracts 3, leaflike, closely subtending flower. Flowers bisexual, radially symmetric; sepals not persistent in fruit, 5--8, yellow, plane, narrowly obovate or elliptic, ca. 15--18 mm; petals 5--8, distinct, yellow [white], cupped around nectary, 2-lipped, ± clawed, ca. 4mm; nectary present; stamens 30--36; filaments filiform; staminodes absent between stamens and pistils; pistils 3--9(--11), 1-carpellate; ovules 6--9 per pistil; style present. Fruit follicles, aggregate, stipitate, flat, [linear] oblong-lanceolate, sides with veins conspicuous upon drying; beak terminal, straight or distally curved, 2--3 mm. Seeds olive-brown, ovoid to ellipsoid, somewhat flattened, smooth. x =8. The seven Asian species are sometimes segregated as Shibateranthis Nakai. Of the species that are cultivated in North America, only one is known to escape and infrequently become established; more often it is found persisting after cultivation.