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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.

Lygodactylus is the most speciose gekkonid group in Africa, with several additional, candidate species already identified from previous studies. However, in mainland Africa, several groups remain only partially resolved, and there are several taxonomic inconsistencies. Lygodactylus gutturalis was described from Guinea-Bissau in the 1870s and since then, the species has been recorded from West to East Africa, and it is widely distributed through different biomes and ecoregions. However, this taxon has never been studied in detail. In this work, we use an integrative approach, including molecular phylogenetic analysis, morphometrics, skull osteology, and biogeography to provide the first systematic revision of the L. gutturalis species complex. The L. gutturalis complex is a subgroup within the L. picturatus group and includes nine well-differentiated species. We elevate Lygodactylus gutturalis dysmicus to full species status, recognize Lygodactylus depressus as the sister species to L. gutturalis , describe five new species (Lygodactylus kibera sp. nov. , Lygodactylus karamoja sp. nov. , Lygodactylus mirabundus sp. nov. , Lygodactylus leopardinus sp. nov. and Lygodactylus gamblei sp. nov.), and propose an additional candidate species that requires further research. Also, in order to shed light on some taxonomic inconsistencies between the L. gutturalis and Lygodactylus angularis groups, we revisit the L. angularis group, within which we elevate Lygodactylus angularis heeneni and Lygodactylus angularis paurospilus to full species status. The L. gutturalis subgroup diversified during the Late Miocene (between 5–15 Mya), probably as a consequence of multiple vicariant events driven by the expansion of the African savannahs and the establishment of climatic refugia. [ABSTRACT FROM AUTHOR]

Given the potential impact of climate change on amphibians, there is a need to establish baseline phenological data for vulnerable species and to investigate their responses to changing climatic conditions. We recorded vocalisations of Hewitt's ghost frog Heleophryne hewitti in the Baviaanskloof World Heritage Site, South Africa, to investigate its breeding phenology and vocalisation behaviour. Our objectives were to: 1) characterise seasonal and diel vocalisation patterns, 2) examine relationships between environmental variables and calling behaviour and 3) evaluate the effectiveness of acoustic recording as a monitoring technique. We employed automatic vocalisation recognition software to detect calls and used hurdle regression to model the relationships between environmental variables and the number of calls produced. Our study confirmed that H. hewitti is a seasonal prolonged breeder, with reproductive activity occurring from early to late spring. We found that while relative humidity seemed to influence the probability of calling, none of the weather variables appeared to have a strong influence on the number of calls produced. Acoustic monitoring combined with automatic vocalisation recognition has proven to be a viable technique for monitoring this species. Further investigation of cues for breeding initiation is required to understand the impacts of climate change on this species. [ABSTRACT FROM AUTHOR]

We use mitochondrial and nuclear gene sequences and morphology to re-evaluate the taxonomy of Bufo vertebralis grindleyi Poynton, 1963, currently a junior synonym of Poyntonophrynus fenoulheti (Hewitt & Methuen, 1912); and morphology and advertisement calls to re-evaluate the status of Bufo jordani Parker, 1936, currently a junior synonym of Poyntonophrynus hoeschi (Ahl, 1934). According to our results including comparisons to other congeners, we elevate both taxa to full species as Poyntonophrynus grindleyi (Poynton, 1963) and Poyntonophrynus jordani (Parker, 1936). Our new P. grindleyi record is the first record of the species for Mozambique. [ABSTRACT FROM AUTHOR]