Phylogenetic relationships of Vepris (Rutaceae) inferred from chloroplast, nuclear, and morphological data

The tribe Toddalieae Hook. F. (Rutaceae) has been controversial since its inception by Bentham and Hooker. The nine taxa examined, Acronychia J.R. & G. Foster, Diphasia Pierre, Diphasiopsis Mendonca, Fagaropsis Mildbr. ex. Siebenl., Oricia Pierre, Teclea Delile, Toddaliopsis Engl., Toddalia Juss. and Vepris Comm. ex. A. Juss, have been recognized under the tribe Toddalieae or Tribes Acronychia, Phellodendron and Toddalia. More recently Araliopsis Engl., Diphasia, Diphasiopsis, Oricia, Teclea, and Toddaliopsis have been incorporated into the genus Vepris, while Toddalia and Fagaropsis have continued to be recognized as closely related. For this study, sequence data of one non-coding chloroplast region (trnL-F) and one nuclear region (ITS) and various morphological characters, based on Mziray's taxonomic studies were examined to try to elucidate these relationships. This study found that the taxa Diphasia, Diphasiopsis, Oricia, Teclea, Toddaliopsis, Vepris, Toddalia eugeniifolia Engl. and Toddalia glomerata F. Hoffm. form a monophyletic group. Due to the amount of intrageneric and intraspecific variation, species delimitations were difficult to determine; however, these genera should be united into Vepris. The analyses also confirmed that Toddalia asiatica (L.) Lam., Zanthoxylon sp. and Fagaropsis angolensis (Engl.) H.M. Gardner are the closest relatives to this group.