Aim Montane tropics are areas of high endemism, and mechanisms driving this endemism have been receiving increasing attention at a global scale. A general trend is that climatic factors do not explain the species richness of species with small to medium-sized geographic ranges, suggesting that geological and evolutionary processes must be considered. On the African continent, several hypotheses including both refugial and geographic uplift models have been advanced to explain avian speciation and diversity in the lowland forest and montane regions of central and eastern Africa; montane regions in particular are recognized as hotspots of vertebrate endemism. Here, we examine the possible role of these models in driving speciation in a clade of African forest robins. Location Africa.Methods We constructed the first robustly supported molecular phylogenetic hypothesis of forest robins. On this phylogeny, we reconstructed habitat-based distributions and geographic distributions relative to the Albertine Rift. We also estimated the timing of lineage divergences via a molecular clock. ResultsRobust estimates of phylogenetic relationships and clock-based divergences reject Miocene tectonic uplift and Pleistocene forest refugia as primary drivers of speciation in forest robins. Instead, our data suggest that most forest robin speciation took place in the Late Pliocene, from 3.2 to 2.2 Ma. Distributional patterns are complex, with the Albertine Rift region serving as a general east-west break across the group. Montane distributions are inferred to have evolved four times.Main conclusions Phylogenetic divergence dates coincide with a single period of lowland forest retraction in the late Pliocene, suggesting that most montane speciation resulted from the rapid isolation of populations in montane areas, rather than montane areas themselves being drivers of speciation. This conclusion provides additional evidence that Pliocene climate change was a major driver of speciation in broadly distributed African animal lineages. We further show that lowland forest robins are no older than their montane relatives, suggesting that lowland areas are not museums which house 'ancient' taxa; rather, for forest robins, montane areas should be viewed as living museums of a late Pliocene diversification event. A forest refugial pattern is operating in Africa, but it is not constrained to the Pleistocene.

The genus Monticola consists of 13 putative species with distributions throughout Eurasia and the sub-Saharan region of Africa. As such, this genus provides an excellent model with which to explore historical intercontinental movements and forces driving speciation in southern Africa. To address these questions, we reconstructed a hypothesis of species relationships using the mitochondrial ND2 and cytochrome-b genes. Monticola forms a well-supported, monophyletic clade within the avian family Muscicapidae. Our results support previous studies suggesting that the Malagasy genus Pseudocossyphus be subsumed into Monticola, and suggest that several of the Malagasy species (notably M. bensoni and M. erythronotus) are not valid. Sequence data, along with morphological and distributional evidence, support the elevation of M. pretoriae to species status. Historical biogeographic analyses suggest an area of origin for Monticola in the arid region of northern Africa plus Saudi Peninsula or the African savanna, or both. Determination of speciation timing suggests that Monticola arose ≈5.5 mya, with subsequent lineage splits occurring throughout the Pliocene and Pleistocene. We propose that climate-driven ecological vicariance as well as dispersal were important in the biogeographic history of this group and are responsible for present-day species relationships and distributions.Systématique moléculaire et biogéographie historique des monticoles (Muscicapidae: Monticola)

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Résumé.-Nous décrivons ici Laniarius willardi, une nouvelle espèce de la famille des Malaconotidae vivant au Rift Albertine, en Afrique. Le caractère morphologique le plus remarquable de cette espèce est un iris gris à bleu-gris. Ceci et des données morphométriques externes indiquent que L. willardi est différent des autres Laniarius. De plus, L. willardi est génétiquement différent et son plus proche parent est L. poensis camerunensis, au Cameroun. L. atrococcineus et L. leucorhynchus forment le clade saeur de L. willardi-L. p. camerunensis. L. willardi et L. p. holomelas, dont la répartition géographique est similaire, diffèrent de , % en ce qui concerne la divergence de la séquence corrigée. Les données altitudinales récoltées sur des spécimens de musée suggèrent qu'il existe une possibilité de ségrégation altitudinale des espèces à ~  m, L. willardi étant présent à des altitudes plus faibles. Notre vaste échantillonnage de ce taxon indique que () les races L. poensis ne forment pas un clade monophylétique, () L. p. camerunensis peut représenter des lignées multiples qui ne sont pas saeurs et () au moins une race de L. fuelleborni usambaricus est génétiquement distincte des autres races de cette espèce.-678 - In , T.P.G., C.K., and B.D.M. conducted collections-based field work in the southern region of Uganda, in the Albertine Rift system. Their survey was conducted on privately held property primarily used as a banana plantation, which included the only forest contiguous with the Bwindi Impenetrable National Park in the area. During this survey, they collected  black Laniarius specimens that they were forced to attribute to L. poensis holomelas on the basis of size and plumage characteristics. However, these specimens, and an additional Field Museum of Natural History (FMNH) specimen collected in Burundi in , were noted as having a unique iris color (gray to blue-gray) unlike that shown for any black Laniarius species in field guides (reddish-black to black). We could find no published reports describing blue-gray irides in adults of black Laniarius species, which reinforced concerns about the identification of these specimens (Marks et al. ).Further questions related to species limits and taxonomy of black Laniarius species are raised by the broader distributions of L. poensis and L. fuelleborni. The former has a significant geographic disjunction between subspecies in the Albertine Rift and Mt. Cameroon (Fig. ), and the latter has populations isolated on different mountains of the Eastern Arc, as well as a population in southwestern Tanzania and northern Malawi (Fry et al. ). Taxonomically, these two species have been linked; races of L. poensis were historically recognized as subspecies of L. fuelleborni (Mayr and Greenway ). Also, L. poensis and L. fuelleborni along with L. leucorhynchus are considered a superspecies (Fry et al. ). However, no phylogenetic study has addressed the relationships among these populations.We had two goals in the present study. First, we con...

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