5. Oxyspora Candolle, Prodr. 3: 123. 1828.
尖子木属 jian zi mu shu
Shrubs. Stems 4-sided or obtusely 4-sided, channeled. Leaves petiolate; leaf blade stiffly papery to sometimes membranous, secondary veins 2 or 3 on each side of midvein, margin denticulate. Inflorescences terminal, a cymose panicle, with 2(or 3) leaflike bracts at base. Bractlets and bracteoles very small, caducous. Flower 4-merous. Hypanthium narrowly funnelform, 8-veined. Calyx lobes shortly and broadly triangular or shortly triangular-ovate, apex acute and apiculate. Petals pink, red, or dark red, ovate, apex apiculate and puberulous. Stamens 8, whorls unequal in length. Longer stamens purple; connective swollen and usually not extended at base into a spur. Shorter stamens yellow; connective usually extended at base into a short spur. Ovary inferior, 4-celled, glabrous. Capsule obovoid or ovoid, 4-poricidal; hypanthium narrowly funnelform, apically contracted, 8-ribbed. Seeds numerous, small, triangular-lanceolate, angular.
Number of species unclear: Bhutan, Cambodia, China, India, Laos, Myanmar, Nepal, Thailand, Vietnam; four species (one endemic) in China.
The number of species in Oxyspora is unclear because of problems with the separation from Allomorphia (see comment under that genus above).