Description from Flora of China
Herbs annual, covered with stellate hairs. Stems decumbent, ascending, or erect. Leaves alternate, petiolate; leaf blade flattened, lanceolate to ovate, margin entire. Flowers unisexual (plants monoecious). Male flowers sessile, several glomerulate in axils of upper branches and forming a spike; bracts and bractlets absent; perianth segments 3-5, obovate or elliptic, membranous, densely stellate pubescent abaxially, without appendages; disk absent; stamens 2-5; filaments linear; anthers broadly oblong; ovary rudimentary. Female flowers inserted on petiole of bract; bracts green, elliptic, midvein abaxially prominent; bractlets absent; perianth segments 3 or 4, membranous, without appendages, enlarged in fruit; ovary ovoid; style short; stigmas 2. Fruit a utricle, compressed, ellipsoid or ovoid, glabrous or wrinkled, usually with a crestlike appendage. Seed vertical; embryo semi-annular; radicle inferior; perisperm copious.
About six species: Asia, SE Europe; three species in China.