Rampant non-monophyly of species in Kniphofia Moench (Asphodelaceae) suggests a recent Afromontane radiation.

The genus Kniphofia, comprising 71 species, has an African-Malagasy distribution, with one species from Yemen. The genus is found predominantly in moist temperate montane grassland and has its centre of diversity in the Drakensberg region of southern Africa. The genus has a complex alpha taxonomy and species relationships are poorly understood. Using a multiple exemplar approach, DNA sequence data from the chloroplast trnT-L spacer and the nuclear internal transcribed spacer region were used in an attempt to resolve phylogenetic relationships: Five cpDNA lineages were recovered, the geographic distributions of which correspond well with previously identified Afromontane centres of diversity and endemism. The data revealed that several morpho-species were non-monophyletic, and this, together with short branch lengths and many identical sequences within each of the five lineages, suggests a recent radiation. We additionally propose that hybridisation and! or incomplete lineage sorting may also account for this result. The nrlTS region was largely uninformative as many taxa and samples had identical sequences. We hypothesise that Kniphofia experienced periods of range expansion, secondary contact and hybridisation during Pleistocene glacial periods, followed by contraction, fragmentation and isolation in montane refugia during the warmer interglacial periods. [ABSTRACT FROM AUTHOR]