Phylogeny of Dorstenia (Moraceae) reveals the polyphyletic nature of its neotropical sections

Abstract

Abstract Dorstenia, the second largest genus of Moraceae, comprises nine sections that are mainly found in Africa and America. Two of them are woody macrospermous, and the other seven are herbaceous microspermous. There are three sections in the Neotropics, all of which are herbaceous and taxonomically complex owing to their great morphological similarity. The most recent molecular phylogenetic studies of Dorstenia suggested that the neotropical sections are polyphyletic. These studies also showed that the neotropical species represent a sister group to an African woody macrospermous grade rather than African herbaceous microspermous plants. We have now expanded the number of taxa sampled and included other molecular markers to determine whether the previous phylogeny are to be corroborated or whether new taxonomic interpretations are to be followed. This study inferred the phylogeny of the group based on ITS, ETS, and trnL-F regions from 40 of the 58 neotropical species and added a new African taxon, thus including 17 of the 60 known species. Our results reaffirmed the polyphyletic nature of the neotropical sections. Dorstenia sect. Acauloma emerged within the main clade of D. sect. Kosaria (both African species), a result that confirms the affinity of these taxa already observed in previous morphological studies. We suggest Dorstenia sect. Dorstenia as the only neotropical section.

Keywords

• molecular markers
• neotropics
• phylogeny
• plant evolution
• rosids