With approximately 1500 species, the genus Peperomia is one of the largest genera of the Basal Angiosperms. As a result of this huge number of taxa and because of the numerous synonyms, the actual taxonomic knowledge of the genus is quite chaotic. Because of its wide range of morphological forms, it can give us a basis for hypotheses on evolutionary processes as well. The apparent uniformity of the minute flowers in the genus presents a challenge to developing an infrageneric classification. The currently accepted infrageneric classification includes some 400 species and is primarily based on the shape of the drupes (Dahlstedt 1900). Other possibly important characters useful for an infrageneric classification have never been thoroughly studied. Most species described after 1900 have been described without reference to subgeneric affiliation. To develop further our understanding of patterns of diversification within Peperomia, the distribution of morphological changes and/or combinations of character states needs to be examined within a phylogenetic context.

The first modest attempts to make order out of chaos are to gain insight into the infrageneric relationships, to resolve some small well defined groups within the genus and to produce an interactive key to the species. The ultimate target is to make a worldwide monograph of the genus Peperomia. The molecular work is carried out in cooperation with Stefan Wanke (Institut für Botanik, Technische Universität Dresden). The following scientific tools are available online: the Taxonomic Repertorium of the Genus Peperomia (TRGP), the Peperomia Bibliography Online (PBO) and a digital photo library (peperomia.net). The presence of the Peperomia Reference Collection in the Botanical Garden of Ghent University is invaluable. This collection now includes some 1000 specimens of approximately 350 species of the different subgenera and is the largest and most representative ex-situ living collection of Peperomia­-species in the world.