This is one of the commonest small trees in the area. A mature individual can reach up to 14 cm in trunk diameter. The large, simple opposite leaves have long petioles which are slightly swollen at the top and bottom. Often one leaf in each pair is smaller than the other one. The white flowers form a little pyramid-shaped inflorescence at the tops of the branches. The woody fruit split to reveal two seeds. The genus Thomandersia consists of six species all restricted to the forest zone of west and central Africa. It used to be in the Acanthaceae but has been moved to a family of its own. The hard wood of this species always made it an exception when it was in the Acanthaceae, which is a family predominately of herbs.
This species occurs in both well-lit and shady locations in terra firma forest and occasionally seasonally flooded areas. Chimpanzees use this species for tools.
Distribution: Nigeria to DRC and Gabon.