Nomenclatural notes on southern African Oxalis species

Background:  The correct author citation of  Oxalis sonderiana  (Kuntze) J.F.Macbr. and the validity and identity of the species  Oxalis beneprotecta  R.Knuth,  Oxalis bullulata  T.M.Salter and  Oxalis pulchella  Jacq. var.  beneprotecta  (R.Knuth) T.M.Salter are unclear. Objectives:  To resolve the nomenclatural and taxonomic confusion surrounding these four taxa. Method:  We studied relevant herbarium records (especially type material) of all the taxa, and paired this with scrutiny of all publications that bear reference to the nomenclature and taxonomy of these species. Results:  The correct author citation for  Oxalis sonderiana  has been determined;  Oxalis bullulata  is confirmed as a distinct species, and the continued recognition of  Oxalis beneprotecta  as a variety of  Oxalis pulchella  is suggested. It is further ascertained that the name ‘ Oxalis nidulans  Turcz.’ is not a later homonym, but a reference to a misapplication of  Oxalis nidulans  Eckl. & Zeyh. to the type specimen of  Oxalis sonderiana . Conclusion:  These results clarify the current confusion surrounding these taxa in global herbaria and in national and international databases.