Isolona zenkeri is a species of plant in the Annonaceae family. It is found in Cameroon, The Republic of the Congo and Gabon.[1] Adolf Engler, the German botanist who first formally described the species, named it after Georg August Zenker who collected the sample Engler examined.[2] Its natural habitat is subtropical or tropical moist lowland forests. It is threatened by habitat loss.
It has dark smooth branches. Its leaves are 20-25 by 7-9 centimeters and come to a point at their tip.