Description from
Flora of China
Herbs, annual or perennial, without latex; monoecious. Stipules free, lateral, caducous. Leaves alternate, distichous; leaf blade margin toothed. Inflorescences axillary, usually bisexual, cymose, racemose, or spicate, shortly pedunculate, bracteate. Male flowers: calyx campanulate, 4-lobed, valvate; stamens inflexed in bud. Female flowers: sessile; calyx boat-shaped, 4-6-lobed, valvate; ovary free; style lateral; stigma 2-branched, filiform. Fruit free, not fleshy. Achenes small, oblique globose, ± compressed, enclosed by an enlarged calyx. Seed with a membranous coat; endosperm absent; cotyledon wide; embryo incurved.
Two species: Asia, Australia, Pacific Islands; two species in China.