Tribal delimitation in the Apocynaceae has traditionally been based on fruit and seed characters. These were especially important in the basalmost subfamily, Rauvolfioideae (usually called "Plumerioideae"), where the flowers are often superficially similar, with relatively unspecialized organs and few distinguishing morphological characteristics. Results of various, mostly molecular, studies in recent years, however, suggest that the fruit-based classifications did not yield monophyletic groups. Here we focus on one such group of the Rauvolfioideae, which has usually been treated as a tribe called the "Rauvolfieae" or "Alyxieae", and characterized by having drupaceous fruits. This study is based on a combined analysis from five data sets, including four genes (matK, rbcL, trnL intron and trnL-F spacer) and 54 morphological characters. In the consensus trees from each individual data set the bulk of the genera fall within two clades, which have been re-circumscribed as Alyxieae and Vinceae. In the combined matrix consensus tree the traditional "Alyxieae" is polyphyletic, with genera dispersed over 4 separate clades. This exemplifies the ease with which fruits may switch back and forth from dry to fleshy and/or dehiscent to indehiscent, or seeds independently evolve similar structures to aid in dispersal in response to selective pressures. It also bodes ill for delimitation of higher taxonomic categories based on traditional fruit and seed characters elsewhere in the family, and should serve as a warning in other families in the Gentianales as well, such as Rubiaceae, where fruit characters have played an important role in classification. Combining morphological and molecular methods allows us to glimpse how much more intricate the evolutionary pathways are than previously imagined and provides a groundwork on which to study character evolution.

Key words: Alyxieae, Apocynaceae, fruit and seed character evolution, Rauvolfieae, Rauvolfioideae