Description from
Flora of China
Trees or shrubs. Leaves paripinnate, alternate, petiolate; leaflets usually 1 or 2 pairs, sometimes 3 pairs, entire. Thyrses axillary or terminal, unbranched or many branched; bracts and bracteoles small. Flowers unisexual, actinomorphic, small. Sepals 4 or 5, suborbicular, concave, imbricate. Petals 4 or 5, usually jointed long villous. Disk annular, crenately lobed, lobes opposite to sepals. Stamens (male flowers) 8, inserted on disk, exserted; filaments villous; anthers broadly ovoid, small. Ovary (female flowers) obcordiform, 2-lobed, 2-loculed, abaxially tuberculous; ovules 1 per locule; style inserted between ovary lobes, short, apex inflated, inconspicuously 2-lobed. Fruit deeply lobed into 2 schizocarps, usually only 1 developed, ellipsoid or subglobose, abaxially usually tuberculous, rarely smooth. Seeds same as schizocarps in shape; arillode adnate to testa; embryo thick.
About 20 species: tropical Asia; one species in China.