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Organismal traits interact with environmental variation to mediate how species respond to shared landscapes. Thus, differences in traits related to dispersal ability or physiological tolerance may result in phylogeographic discordance among co-distributed taxa, even when they are responding to common barriers. We quantified climatic suitability and stability, and phylogeographic divergence within three reed frog species complexes across the Guineo-Congolian forests and Gulf of Guinea archipelago of Central Africa to investigate how they responded to a shared climatic and geological history. Our species-specific estimates of climatic suitability through time are consistent with temporal and spatial heterogeneity in diversification among the species complexes, indicating that differences in ecological breadth may partly explain these idiosyncratic patterns. Likewise, we demonstrated that fluctuating sea levels periodically exposed a land bridge connecting Bioko Island with the mainland Guineo-Congolian forest and that habitats across the exposed land bridge likely enabled dispersal in some species, but not in others. We did not find evidence that rivers are biogeographic barriers across any of the species complexes. Despite marked differences in the geographic extent of stable climates and temporal estimates of divergence among the species complexes, we recovered a shared pattern of intermittent climatic suitability with recent population connectivity and demographic expansion across the Congo Basin. This pattern supports the hypothesis that genetic exchange across the Congo Basin during humid periods, followed by vicariance during arid periods, has shaped regional diversity. Finally, we identified many distinct lineages among our focal taxa, some of which may reflect incipient or unrecognized species. [ABSTRACT FROM AUTHOR]

Abstract Aim We propose a phylogeny of selected Hyperolius species (Anura: Hyperoliidae), based on mtDNA sequence data and parsimony analysis. This phylogeny was used to interpret the historical biogeography of the genus in Africa. Location Samples were collected throughout the distribution of Hyperolius in Africa. Methods We compiled distributional maps of all species, summarized historical changes in vegetation and climate in Africa since the late Cretaceous, and used these in combination to identify historical factors that may have contributed to speciation in these frogs. A phylogeny for Hyperolius was derived from mtDNA sequence data and interpreted in terms of climatic and vegetation changes in Africa. Main conclusions Lowland rainforest is proposed to have been the ancestral habitat of Hyperolius . The expansion of savannah and reduction of lowland rainforest were identified as important factors in the differentiation of the more basal species. Finally, the development of the Rift Valley system played an important role in the speciation of derived species with relatively limited distributions. [ABSTRACT FROM AUTHOR]