A multi-disciplinary approach based on extensive field work and herbarium specimens was followed towards a revision of Lobostemon. Morphological characters pertaining to especially the flowers were supplemented by leaf indumentum and anatomy, as well as fruit and anthocyanin data. Diagnostic characters are largely confined to the flowers and to a lesser extent to the leaves and fruit. Twenty eight species of Lobostemon are recognised and a number of informal infraspecific entities are documented. A cladistic analysis of morphological data resulted in revised sectional delimitations and sister-taxon relationships. The taxonomic treatment includes a brief historical review of Lobostemon, a discussion of pertinent characters and character states, phytogeographical analyses, keys to the sections and species, detailed descriptions with nomenclatural and taxonomic notes, as well as comments on distribution, ecology and conservation status. Illustrations and distribution maps are provided for each species.

Key words: Boraginaceae, Lobostemon, revision, South Africa, taxonomy