Description from Flora of China
Trees. Leaves alternate, bipinnate; stipules caducous, small; pinnae few pairs, opposite; leaflets alternate, leathery. Flowers small, crowded together in terminal panicles of spicate racemes. Calyx campanulate, with 5 short subequal lobes; tube short. Petals 5, subequal. Stamens 10, free; filaments equal or alternately longer and shorter. Ovary stalked, hairy; ovules numerous; style short; stigma small. Legume compressed, long, thickly leathery, 2-valved dehiscent when ripe, pulpy within between seeds. Seeds transverse, oblong or obovoid, compressed, with endosperm.
About 15 species: tropical Africa, tropical and subtropical E Asia, and N Australia; one species in China.
(Authors: Chen Dezhao (陈德昭 Chen Te-chao), Zhang Dianxiang (张奠湘); Kai Larsen)