Description from Flora of China
Shrubs, subshrubs, or herbs, without stinging hairs. Leaves alternate or rarely opposite; stipules often persistent, lateral, free; leaf blade 3-veined or triplinerved, margin serrate, dentate, or entire; cystoliths punctiform. Glomerules axillary or rarely at nodes along rachis of spikes, bisexual or rarely unisexual (plants monoecious or dioecious); bracts and bracteoles small. Male flowers: perianth lobes (3 or)4 or 5, connate ca. 1/2 of length, valvate, apex concave; stamens as many as perianth lobes; filaments inflexed in bud; rudimentary ovary present. Female flowers: perianth tubular, often ovoid, beaked, constricted, apex 2-4-toothed. Ovary included; style present; stigma filiform, villous along 1 side, deciduous with style; ovule orthotropous. Achene pericarp often crustaceous, lustrous. enclosed by marcescent, always accrescent, and often ribbed, rarely winged, perianth. 2n = 20, 22, 24, 26, 32.
Some woody taxa are used as sources of fiber.
About 37 species: pantropical; four species (one endemic) in China.
(Authors: Chen Jiarui (陈家瑞 Chen Chia-jui); Ib Friis, C. Melanie Wilmot-Dear)