A monograph of Cupaniopsis Radlk. (Sapindaceae) recognized. One species, is presented. Sixty species (20 new) are C. macrocarpa, is subdivided into two varieties (one new). Several regional keys and a multy-entry key give access to the species. Pollen morphology and leaf anatomy were studied beside macromorphology. This resulted in 40 characters for a cladistic analysis. The result of an initial analysis was rejected for several reasons (chapter 10.5). Van Welzen’s enhancement method was used to produce a more acceptable cladogram (chapter 10.6). A short note on the biogeography is given.