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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]

Discusses the problems of assigning species labels to taxa in the group of cryptic species of sharp-nosed reed frogs found in localities in the western to southern parts of Africa. Analysis of the three groups of calls associated with cryptic species; Comparison of advertisement and aggression call parameters of three species; Recommendations for a revised taxonomy of the group.

Frogs of the genus Tomopterna occur throughout sub-Saharan Africa. Previous work has shown that there are seven cryptic species, which occupy diverse habitats from grasslands to deserts. The current paper proposes a phylogeny of Tomopterna based on partial sequences of the mitochondrial 12S rRNA gene. A gene tree for the genus, including all seven named species and three undescribed species which were discovered during the course of this study, is presented. [Copyright &y& Elsevier]

The taxonomy of the Hyperolius viridiflavus complex, a group of African frogs, has been problematic. Mitochondrial DNA sequence data were used to reconstruct the phylogenetic history of these frogs. The phylogeny showed that subspecies were grouped into clades, within which certain taxa were not supported by fixed characters. We used the phylogenetic species concept to identify the smallest monophyletic clades supported by at least one fixed character, and suggest taxonomic revisions based on our results. We identify ten species within the H. viridiflavus complex. [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]

Sub-Saharan Africa is under-represented in global biodiversity datasets, particularly regarding the impact of land use on species' population abundances. Drawing on recent advances in expert elicitation to ensure data consistency, 200 experts were convened using a modified-Delphi process to estimate 'intactness scores': the remaining proportion of an 'intact' reference population of a species group in a particular land use, on a scale from 0 (no remaining individuals) to 1 (same abundance as the reference) and, in rare cases, to 2 (populations that thrive in human-modified landscapes). The resulting bii4africa dataset contains intactness scores representing terrestrial vertebrates (tetrapods: ±5,400 amphibians, reptiles, birds, mammals) and vascular plants (±45,000 forbs, graminoids, trees, shrubs) in sub-Saharan Africa across the region's major land uses (urban, cropland, rangeland, plantation, protected, etc.) and intensities (e.g., large-scale vs smallholder cropland). This dataset was co-produced as part of the Biodiversity Intactness Index for Africa Project. Additional uses include assessing ecosystem condition; rectifying geographic/taxonomic biases in global biodiversity indicators and maps; and informing the Red List of Ecosystems., (© 2024. The Author(s).)

Theory predicts that sexually dimorphic traits under strong sexual selection, particularly those involved with intersexual signaling, can accelerate speciation and produce bursts of diversification. Sexual dichromatism (sexual dimorphism in color) is widely used as a proxy for sexual selection and is associated with rapid diversification in several animal groups, yet studies using phylogenetic comparative methods to explicitly test for an association between sexual dichromatism and diversification have produced conflicting results. Sexual dichromatism is rare in frogs, but it is both striking and prevalent in African reed frogs, a major component of the diverse frog radiation termed Afrobatrachia. In contrast to most other vertebrates, reed frogs display female-biased dichromatism in which females undergo color transformation, often resulting in more ornate coloration in females than in males. We produce a robust phylogeny of Afrobatrachia to investigate the evolutionary origins of sexual dichromatism in this radiation and examine whether the presence of dichromatism is associated with increased rates of net diversification. We find that sexual dichromatism evolved once within hyperoliids and was followed by numerous independent reversals to monochromatism. We detect significant diversification rate heterogeneity in Afrobatrachia and find that sexually dichromatic lineages have double the average net diversification rate of monochromatic lineages. By conducting trait simulations on our empirical phylogeny, we demonstrate that our inference of trait-dependent diversification is robust. Although sexual dichromatism in hyperoliid frogs is linked to their rapid diversification and supports macroevolutionary predictions of speciation by sexual selection, the function of dichromatism in reed frogs remains unclear. We propose that reed frogs are a compelling system for studying the roles of natural and sexual selection on the evolution of sexual dichromatism across micro- and macroevolutionary timescales., (© The Author(s) 2019. Published by Oxford University Press, on behalf of the Society of Systematic Biologists. All rights reserved. For permissions, please email: journals.permissions@oup.com.)