An updated inventory of medicinal and ritual plants of southern Africa

Ethnopharmacological relevance: For the first time in two decades, a comprehensive, up-to-date overview of the medicinal and ritual plants of southern Africa is presented. This data is analysed and compared with a previous survey done in 2002. Study aim: The main aim is to update the checklist of medicinal and ritual plants of southern Africa and to determine the number of new records since 2002. We also provide a high-level perspective on the selection of medicinal and ritual plant species in southern Africa, a taxonomic analysis of the new checklist as well as a chronological perspective on the citation of medicinal and ritual species before and after 2002. Materials and methods: The most recently published medicinal and ritual plants checklist for southern Africa was reviewed and updated. A wide range of ethnobotanical literature, including books, field guides and electronic journals, was used. All calculations were done by using formulas and functions in Microsoft Excel and R Studio. Results: 4120 medicinal and ritual taxa and 3784 medicinal and ritual species have been recorded. Compared with the 2002 checklist, there are 1239 new taxa (1228 new species). A strong correlation between available taxa and selected medicinal taxa exists on order level, which corresponds with the results of an analysis done in 2008. The top 10 species-rich medicinal plant families of southern Africa are Asteraceae, Fabaceae, Apocynaceae, Euphorbiaceae, Asphodelaceae, Malvaceae, Lamiaceae, Poaceae, Rutaceae and Rubiaceae. Different patterns of plant family representation can be seen across certain cultural healing systems of southern Africa. The species popularity (number of citations) of Hypoxis hemerocallidea Fisch. & C.A.Mey. Has increased substantially after 2002. Other medicinal and ritual plant species have been consistently researched, such as Artemisia afra Jacq. ex Willd., Carpobrotus edulis (L.) L.Bolus, Aloe ferox Mill., Leonotis leonurus (L.) R.Br. and Gunnera perpensa L. Conclusions: The numerous new medicinal and ritual plant records that have been reported in the last two decades provide evidence of an incompletely documented ethnobotanical heritage that urgently requires documentation. Patterns of taxonomic diversity on family level indicate distinctive differences between cultural healing systems. Signs of the adaptability and dynamics of traditional healing systems in southern Africa can be seen in the changes in the citation of species over time.