Molecular systematics of Alethe, Sheppardia and some other African robins (Muscicapoidea)

Phylogenetic relationships between species of akalats (Sheppardia) and alethes (Alethe) were derived from mitochondrial and nuclear sequence data, and phylogeographic pattern was also investigated in three widespread species (two Alethe and one Sheppardia) endemic to the African lowland rainforest biome. Co-distributed species of Alethe and Sheppardia showed similar spatial relationships between the Guineo-Congolian biome and the Western Rift mountains, and preliminary area relationships are shown for species of Sheppardia and Alethe distributed in the Cameroon highlands, the woodland areas north and south of the lowland forest block, and east African montane and lowland forest. Within widespread species, phylogeographic pattern was generally similar, with long branches between Upper and Lower Guinea populations, and between eastern and western Congolian populations. At the interspecific level, the nuclear intron used gave more resolution than the mitochondrial data, which gave poor resolution at basal nodes. While the affinities of some species groups were weakly supported, no support was suggested for the monophyly of Alethe and little for Sheppardia as those genera are currently circumscribed, and taxonomic changes are suggested. As found by previous workers, monophyletic clades corresponding to Muscicapini and Saxicolini of Sibley and Ahlquist (1990) were not recovered, and the membership of any monophyletic 'African forest robin assemblage' needs to be resolved.