The emerging phylogenetic estimate for the Lobeliaceae based on chloroplast DNA sequence variation shows strong phylogenetic and biogeographic patterns. Lobelia is the ‘core genus’ of the family, from which the remaining genera in the family have evolved. Twenty of the 30 segregate genera have been surveyed to-date. In most cases, these segregate genera are closely related to Lobelia species from the same geographic area in which the segregate genus occurs. These strong biogeographic affinities are also observed within Lobelia, with a few notable exceptions. The Lobeliaceae originated in southern Africa, and relatively few long-distance dispersal events are needed to account for their almost cosmopolitan, contemporary distribution. However, part of the taxonomic diversity in Australasia is due to repeated introductions, and the pantropical distribution of the giant lobelias is due to successive dispersal events.

Key words: Africa, biogeography, chloroplast DNA, Lobelia, Lobeliaceae, phylogeny