Systematic relationships in southern African Oxalis L. (Oxalidaceae): congruence between palynological and plastid trnL ­ F evidence

In the most recent morphology­based taxonomic classification of African Oxalis L., 206 species were recognized in nine indigenous southern African sections. A subsequent palynological review of these taxa conflicted with their taxonomic classification. In the present study, phylogenetic relationships within section Angustatae subsection Lineares are re­assessed, using plastid trnL ­ F non­coding DNA sequence data. The results of this study clearly indicate that, based on the DNA evidence, subsection Lineares is non­monophyletic. Previously hypothesized relationships within the subsection are also refuted. In contrast, molecular and palynological data are highly congruent, and both differ substantially from the current morphological classification for subsection Lineares .