Herbs perennial, subshrubs, or shrubs, sometimes epiphytic or epilithic, without stinging hairs. Stems often succulent. Leaves apparently alternate, distichous; nanophylls often present, very small, opposite to developed leaves; stipules intrapetiolar, small, undivided; leaf blade ± fleshy, pinnately veined, base asymmetric, margin usually entire or serrulate; cystoliths linear. Inflorescences axillary, sometimes at leafless nodes, of unisexual flowers (plants monoecious or dioecious); male glomerules in lax cymes or crowded on a small, bractless receptacle; female capitula solitary, subsessile, on fleshy subglobose receptacle; bracteoles present, often spatulate. Male flowers: perianth lobes 4 or 5, segments often valvate; stamens 4 or 5; filaments inflexed in bud; rudimentary ovary globose or obovoid. Female flowers: perianth lobes 3 or 4, very small, boat-shaped, free or connate at base, ± fleshy; staminodes absent. Ovary straight; stigma sessile, penicillate, soon disappearing; ovule orthotropous. Achene ovoid or ellipsoid, not ribbed, enclosed by persistent, fleshy perianth or exserted from small perianth. Seeds without endosperm; cotyledons ovate.

About 20 species: warm-temperate and tropical regions of the Old World; one species in China.

(Authors: Chen Jiarui (陈家瑞 Chen Chia-jui); Ib Friis, C. Melanie Wilmot-Dear)