Picrodendron, from Greek picro bitter and dendron tree referring to the bitter taste of some of the fruits. This family was previously included in Euphorbiaceae s. lat. from which it maybe distinguished by the absence of latex, simple hairs, 2 ovules per locule, leaves often toothed with deciduous glands capping the teeth. Maybe distinguished from Phyllanthaceae by 2 ovules per locule, usually both maturing, the leaves not in one plane or distichous, stamens usually basally connate. Fruit is explosively dehiscent or indehiscent, seeds usually with a caruncle; ant dispersal common.

Petalostigma pubescens or Quinine bush occurs around the campus. The orange fruits are explosively dehiscent.