Perennial herbs, glabrous, erect; stems numerous, unbranched, often almost leafless, annual; rootstock woody. Leaves alternate, entire, fleshy, often deciduous; juvenile leaves often smaller than adult. Inflorescence a terminal cyme of compound dichasia with leaf-like bracts and bracteoles. Flowers bisexual, yellow or cream; pedicels filamentous; sepals 2 or 4, triangular, smooth; petals 2 or 4, hooded or boat-shaped, spirally twisted; stamens 4 or 8; anthers linear-oblong, usually shortly apiculate; ovary 1-celled, winged or ribbed, ovules 4, pendulous, styles 2 or 4, clavate, stigmas capitate, shortly fimbriate. Fruit cream or yellow (or reddish), obovate, ovoid to obovoid, 2–4-winged or -ribbed, wings membranous, usually decurrent on sepals and pedicel, pericarp swollen or membranous; seed 1.
4 species confined to Australia, mostly in drier inland areas of the southern half of the continent.