Roots with hairs. Stems short, slender. Inflorescences racemose. Flowers unisexual or bisexual, pedicellate. Perianth segments 3-8(-10). Stamens 2, 3, or 6; filaments absent or very short; anthers 3- or 4-thecous; connectives not produced into appendages. Carpels numerous; style lateral or basal. Follicles opening by a longitudinal slit.

About 30 species: tropics and subtropics; five species in China.