Description from Flora of China
Trees or tall shrubs, evergreen, with quadrangular or flattened twigs, and accumulating aluminum. Leaves opposite, simple, entire, pinnately veined, secondary and reticulate veins prominent, with short petioles and minute or rudimentary stipules, or stipules absent. Inflorescence terminal or axillary, paniculate, racemose, or spicate. Flowers shortly pedicellate, bisexual or unisexual and plants dioecious, actinomorphic, often perigynous, very small; receptacle broadly campanulate. Sepals 4 or 5, mostly persistent, valvate. Petals ± rudimentary, sometimes absent. Stamens or staminodes as many as and alternating with calyx lobes. Ovary superior or inferior, 2-4(or 5)-carpelled, 1-6-loculed; ovules 1-3 or many per locule, anatropous on axile placentas; style 1; stigma 1. Fruit a papery or woody capsule, 2-6-loculicidally dehiscent, valves often held together apically by persistent style. Seeds few or many, small, flat, with membranous wing, endosperm absent; embryo straight.
Phylogenetic and molecular studies support an early Tertiary dispersal of the family northward from India (Conti et al., Evolution 56: 1931-1942. 2002).
Shia Zhen-dia. 1983. Crypteroniaceae. In: Fang Wen-pei & Chang Che-yung, eds., Fl. Reipubl. Popularis Sin. 52(2): 118-120.
Three or four genera and about ten species: pantropical with three genera in Indo-Malesia, one unispecific genus in S Africa, and one genus in South America (Bolivia and Peru); one species in China.
(Authors: Qin Haining (覃海宁); Anthony R. Brach)