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Schotia has a southern African distribution with a strong affinity to the thicket biome and is a potential indicator of thicket biogeography. This study uses DNA sequence data (from the chloroplast and nuclear genomes) to infer interspecific phylogenetic relationships, to elucidate the evolutionary history of Schotia, and to extrapolate findings to the history of the thicket biome. Four species of Schotia represented by multiple samples were nonmonophyletic for both chloroplast and nuclear markers. These results may be due to hybridization and/or incomplete lineage sorting, which also suggests a recent origin of Schotia morphospecies. The center of genetic and taxonomic diversity of Schotia is the Eastern Cape and partly the Western Cape, coinciding with the hub of present-day thicket distribution. This region is hypothesized as being a refugial area for Schotia (and the associated thicket biome) during glacial periods, with expansion beyond this region during interglacial periods. [ABSTRACT FROM AUTHOR]

Aim The genus Kniphofia contains 71 species with an African–Malagasy distribution, including one species from Yemen. The genus has a general Afromontane distribution. Here we explore whether Kniphofia is a floristic indicator of the Afromontane centre of endemism and diversity. The South Africa Centre of diversity and endemism was explored in greater detail to understand biogeographical patterns. Location Africa, Afromontane Region, southern Africa, Madagascar and Yemen. Methods Diversity and endemism for the genus were examined at the continental scale using a chorological approach. Biogeographical patterns and endemism in the South Africa Centre were examined in greater detail using chorology, phenetics, parsimony analysis of endemicity (PAE) and mapping of range-restricted taxa. Results Six centres of diversity were recovered, five of which are also centres of endemism. Eight subcentres of diversity are proposed, of which only two are considered subcentres of endemism. The South Africa Centre is the most species-rich region and the largest centre of endemism for Kniphofia. The phenetic analysis of the South Africa Centre at the full degree square scale recovered three biogeographical areas that correspond with the subcentres obtained from the chorological analysis. The PAE (at the full degree square scale) and the mapping of range-restricted taxa recovered two and six areas of endemism (AOEs), respectively. These latter two approaches produced results of limited value, possibly as a result of inadequate collecting of Kniphofia species. Only two AOEs were identified by PAE and these are embedded within two of the six AOEs recovered by the mapping of range-restricted taxa. All the above AOEs are within the three subcentres found by chorological and phenetic analysis (at the full degree square scale) for the South Africa Centre. Main conclusions The centres for Kniphofia broadly correspond to the Afromontane regional mountain systems, but with some notable differences. We regard Kniphofia as a floristic indicator of the Afromontane Region sensu lato. In southern Africa, the phenetic approach at the full-degree scale retrieved areas that correlate well with those obtained by the chorological approach. [ABSTRACT FROM AUTHOR]