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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]

The Guttural Toad, Sclerophrys gutturalis, has three established invasive populations on Mauritius, Reunion and in Constantia, a peri-urban area of Cape Town, South Africa. The native range of this toad covers much of central and southern Africa. Here we use mitochondrial DNA (mtDNA) to sample across the range of the natural distribution (from Kenya to South Africa) and compare ND2 and 16S sequences to those from animals sampled from each of the three invasive populations. We show that all invasive populations refer to the same mtDNA clade, which is naturally distributed in north-eastern South Africa, but not from adjoining Mozambique or southernmost Eastern Cape areas. Our findings corroborate previous reports of deliberate introductions from South Africa to Mauritius, and from Mauritius to Reunion. Similarly, our results suggest a single accidental translocation within South Africa from the northeast to Constantia. Our findings highlight the combination of anthropophilic behavior, and extreme long-distance dispersal occurring with accidental translocation for this species. We caution that accidental pathways are likely to continue into the future, with increasing numbers of invasive populations of this species. [ABSTRACT FROM AUTHOR]

The phylogenetic relationships of the African mongrel frog genus Nothophryne are poorly understood. We provide the first molecular assessment of the phylogenetic position of, and diversity within, this monotypic genus from across its range—the Afromontane regions of Malawi and Mozambique. Our analysis using a two-tiered phylogenetic approach allowed us to place the genus in Pyxicephalidae. Within the family, Nothophryne grouped with Tomopterna , a hypothesis judged significantly better than alternative hypotheses proposed based on morphology. Our analyses of populations across the range of Nothophryne suggest the presence of several cryptic species, at least one species per mountain. Formal recognition of these species is pending but there is a major conservation concern for these narrowly distributed populations in an area impacted by major habitat change. The phylogenetic tree of pyxicephalids is used to examine evolution of life history, ancestral habitat, and biogeography of this group. [ABSTRACT FROM AUTHOR]