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Although Conraua goliath is well known as the largest living frog species, the diversity and evolution of the genus Conraua across sub‐Saharan Africa remain poorly understood. We present multilocus phylogenetic analyses of the six currently recognized species that provide insights into divergence times, biogeography, body size evolution and undescribed species. An analysis of divergence times demonstrates that crown‐group Conraua arose some time during the latest Oligocene to mid‐Miocene followed by divergence into major lineages in the mid‐Miocene that may reflect the fragmentation of widespread tropical forests in Africa that began at this time. We find three pairs of sister species, C. crassipes + C. beccarii, C. alleni + C. derooi and C. goliath + C. robusta, each of which diverged during the Miocene. These relationships reject phylogenetic hypotheses based solely on biogeography as the geographically peripheral C. beccarii from north‐eastern Africa is nested within western African species and the Central African species do not form a clade. Our species delimitation analyses provide support for undescribed species in C. alleni, C. beccarii and C. derooi, and possibly C. crassipes, suggesting that the current taxonomy substantially underestimates species diversity. There is no clear directional trend of either increasing or decreasing body size in Conraua and the three largest species do not form a clade. With a robust phylogenetic hypothesis in hand, further field‐based studies are needed to understand the evolution of morphology and life history in this charismatic African anuran clade.

West Africa is a region characterised by high species diversity and endemism, making it an ideal region to study the evolution of genetic and phenotypic differentiation. Species in this region ofte...

Forty-nine years after the last description of a slippery frog, we describe a seventh species of the genus Conraua. The new Conraua is endemic to the Atewa Range Forest Reserve, central Ghana, and is described based on genetic, bioacoustics, and morphological evidence. Recent molecular phylogenetic and species delimitation analyses support this population as distinct from nominotypical C. derooi in eastern Ghana and adjacent Togo. The new species is sister to C. derooi, from which it differs ~4% in the DNA sequence for mitochondrial ribosomal 16S. Genetic divergences in 16S to other species of Conraua range from 4–12%. The new species is distinguished morphologically from its congeners, including C. derooi, by the combination of the following characters: medium body size, robust limbs, lateral dermal fringing along edges of fingers, cream ventral color with brown mottling, the presence of a lateral line system, indistinct tympanum, the presence of inner, outer, and middle palmar tubercles, and two subarticular tubercles on fingers III and IV. We compare the advertisement calls of the new species with the calls from C. derooi and find that they differ by duration, frequency modulation, and dominant frequency. We discuss two potential drivers of speciation between C. derooi and the new species, including river barriers and fragmentation of previously more widespread forests in West Africa. Finally, we highlight the importance of the Atewa Range Forest Reserve as a critical conservation area within the Upper Guinean biodiversity hotspot.

Comparative phylogeographic studies often support shared divergence times for co-distributed species with similar life histories and habitat specializations. During the late Holocene, West Africa experienced aridification and the turnover of rain forest habitats into savannas. These fragmented rain forests harbor impressive numbers of endemic and threatened species. In this setting, populations of co-distributed rain forest species are expected to have diverged simultaneously, whereas divergence events for species adapted to savanna and forest-edge habitats should be absent or idiosyncratic. We conducted a Bayesian analysis of shared evolutionary events to test models of population divergence for 20 species of anurans (frogs) and squamates (lizards and snakes) that are distributed across the Dahomey Gap, a climate change-induced savanna barrier responsible for fragmenting previously contiguous rain forests of Ghana into two regions: the Togo-Volta Hills and the Southwestern Forests. A model of asynchronous diversification is supported for anurans and squamates, suggesting that drivers of diversification are not specifically related to ecological and life history associations with habitat types. Instead, the wide variability of genetic divergence histories exhibited by these species suggests that biodiversity in this region has been shaped by diversification events that extend beyond the Holocene. Comparisons of the genealogical divergence index, a measure of the genetic divergence between populations due to the combined effects of genetic isolation and gene flow, illustrate that these populations represent a broad sampling of the speciation continuum.

The savannah and tropical forest biomes of Africa have a long history of expansion and contraction, and the recent and rapid spread of dry savannah habitats has influenced the spatial and temporal diversification of vertebrate taxa across this region. We used a combination of species tree and phylogeographic methods to describe the spatio-temporal changes through time and across space (= species diffusion) in a clade of seven West African lizard species in the Agama agama species group. A Bayesian species tree diffusion approach was used to compare the relative rates at which species ranges changed across the landscape. We found that some species have high diffusion rates characterized by significant movement in their range location and minor changes to their overall range size, whereas other species show little movement in their range centre with an exponential increase in range size. This discrepancy between the rates that range locations shift versus change in their relative area could be linked to pop...

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.

We describe a new species of Phrynobatrachus from swamp forests in the southern border region of Ivory Coast and Ghana. The new species differs from all other known West African Phrynobatrachus by the combination of adult snout-vent-length being between 20 and 30 mm; absence of a spiny tubercle on the eyelid; presence of a dark face mask; a black throat in adult males; narrow and partly indistinct scapular ridges or comma shaped warts; distinct spinulae on males’ throats and dorsal surfaces; pronounced pedal webbing; round finger- and toe tips, not enlarged to discs; a white belly with small blackish spots in both sexes; more than one wide dark cross bar on hind legs; and rosé to reddish colour on ventral parts of hind legs in both sexes. It is further defined by its genetic and acoustic characters. It is morphologically and genetically most similar to P. liberiensis and P. intermedius.

We describe a new species of Phrynobatrachus from the eastern part of the Upper Guinea forest region, Ghana, West Africa. Morphologically, the new species can be distinguished from all of its congeners by the combination of a slender body, short and pointed snout, a relatively warty dorsum, a black-spotted throat in both sexes, a gular flap in males, a dark spotted chest, a white-greyish venter with occasional blackish spots, rudimentary pedal webbing, none to slightly dilated finger tips and strongly delated toe tips, presence of both inner and outer metatarsal tubercles and absence of a dark face mask, eyelid tubercles and longer dorsal ridges. We collected mitochondrial DNA (mtDNA) sequence data from the 16S rRNA gene to measure the genetic diversity of the new species, and to estimate phylogenetic relationships. The new species is a distinct and monophyletic evolutionary lineage most closely related to Phrynobatrachus gutturosus, P. fraterculus and P. maculiventris. The discovery of this new species highlights that the biodiversity of West African forests is still incompletely known and that the few remaining forests need urgent protection.

DNA barcoding has been proposed as a means of quick species identification using a short standardised segment of DNA. The established barcode gene for animals—the mitochondrial gene cytochrome oxidase one (CO1)—has been plagued by primer failure and low species identification success in amphibians. We investigate the accuracy of CO1 barcoding with a new dataset of West African frogs using the universal CO1 primers and new amphibian-specific CO1 primers in comparison to a proposed alternative DNA barcode for amphibians—the mitochondrial ribosomal 16s gene (16s). Research was performed using 134 specimens, comprising 21 species collected in Ghana, a global biodiversity hotspot with a deficiency of amphibian barcoding resources. These species represent 55% of amphibian species (58% of amphibian families) that are known in the area from surveys from 1988 to 2009. We found nearly a 50% increase in PCR amplification success using the amphibian-specific CO1 primers compared to the universal CO1 primers. ...

There is a lack of quantitative information on the effectiveness of selective-logging practices in ameliorating effects of logging on faunal communities. We conducted a large-scale replicated field study in 3 selectively logged moist semideciduous forests in West Africa at varying times after timber extraction to assess post logging effects on amphibian assemblages. Specifically, we assessed whether the diversity, abundance, and assemblage composition of amphibians changed over time for forest-dependent species and those tolerant of forest disturbance. In 2009, we sampled amphibians in 3 forests (total of 48 study plots, each 2 ha) in southwestern Ghana. In each forest, we established plots in undisturbed forest, recently logged forest, and forest logged 10 and 20 years previously. Logging intensity was constant across sites with 3 trees/ha removed. Recently logged forests supported substantially more species than unlogged forests. This was due to an influx of disturbance-tolerant species after logging. Simultaneously Simpson's index decreased, with increased in dominance of a few species. As time since logging increased richness of disturbance-tolerant species decreased until 10 years after logging when their composition was indistinguishable from unlogged forests. Simpson's index increased with time since logging and was indistinguishable from unlogged forest 20 years after logging. Forest specialists decreased after logging and recovered slowly. However, after 20 years amphibian assemblages had returned to a state indistinguishable from that of undisturbed forest in both abundance and composition. These results demonstrate that even with low-intensity logging (≤3 trees/ha) a minimum 20-year rotation of logging is required for effective conservation of amphibian assemblages in moist semideciduous forests. Furthermore, remnant patches of intact forests retained in the landscape and the presence of permanent brooks may aid in the effective recovery of amphibian assemblages. Recuperacion de Ensambles de Anfibios en Dos Etapas Despues de la Tala Selectiva de Bosques Tropicales Resumen Existe una carencia de informacion cuantitativa sobre la efectividad de practicas de tala selectiva en la disminucion de los efectos de la tala sobre comunidades de fauna. Realizamos un estudio de campo replicado a gran escala en 3 bosques humedos semideciduos talados selectivamente en Africa Occidental en diferentes tiempos despues de la extraccion de madera para evaluar los efectos posteriores a la tala sobre ensambles de anfibios. Especificamente, evaluamos si la diversidad, abundancia y composicion del ensamble de anfibios cambiaron en el tiempo en las especies dependientes del bosque y en las tolerantes a la perturbacion del bosque. En 2009 muestreamos anfibios en 3 bosques (un total de 48 parcelas de estudio, de 2 ha cada una) en el suroeste de Ghana. En cada bosque, establecimos parcelas en bosque no perturbado, bosque recientemente talado y bosque talado 10 y 20 anos antes. La intensidad de la tala fue constante en los sitios, con la remocion de 3 arboles/ha. Los bosques recientemente talados soportaron sustancialmente mas especies que los bosques no talados. Estos se debio a la afluencia, despues de la tala, de especies tolerantes a la perturbacion. Simultaneamente, el indice de Simpson decrecio debido a la reduccion en la dominancia de unas cuantas especies. A medida que incremento el tiempo desde la tala, la riqueza de especies tolerantes a la perturbacion decrecio hasta 10 anos despues de la tala cuando su composicion fue indistinguible de la composicion de los bosques no talados. El indice de Simpson incremento con el tiempo desde la tala y fue indistinguible del bosque no talado 20 anos despues de la tala. Los especialistas de bosque decrecieron despues de la tala y se recuperaron lentamente. Sin embargo, despues de 20 anos los ensambles de anfibios habian regresado a un estado no distinguible de los de bosque no perturbado, tanto en abundancia como composicion. Estos resultados demuestran que aun con tala de baja intensidad (≤3) arboles/ha), se requiere una rotacion de 20 anos minimo para la conservacion efectiva de los ensambles de anfibios en bosques humedos semideciduos. Mas aun, los parches remanentes de bosques intactos en el paisaje y la presencia de arroyos permanentes pueden ayudar a la recuperacion efectiva de los ensambles de anfibios.

Making generalizations about the impact of commercial selective logging on biodiversity has so far remained elusive. Species responses to logging depend on a number of factors, many of which have not been studied in detail. These factors may include the natural forest conditions (forest types) under which logging impacts are investigated; but this question has so far remained unexamined. In a large-scale replicate study we aimed at clarifying the relationship between logging and forest types on leaf litter frogs. We contrast three distinct and naturally occurring forest types, including wet evergreen, moist evergreen and semi-deciduous forests. Selectively logged sites were compared with primary forest sites for each forest type. We found that the response of frog communities to logging varies in different forest types. In the wet evergreen forest, richness was higher in logged forest than primary forest, while diversity measures were not different between logged and primary forest habitats. In the moist evergreen, richness and diversity were higher in selectively logged areas compared with primary forest habitats. In the semi-deciduous, logged forests were characterized by drastic loss of forest specialists, reduced richness, and diversity. These results indicate that the net effect of logging varies with respect to forest type. Forest types that are characterized by adverse climatic conditions (i.e., low rainfall and protracted dry seasons) are more likely to produce negative effects on leaf litter anuran communities. For comparisons of the impact of logging on species to be effective, future research must endeavor to include details of forest type.

We report on the results of our assessments of amphibians in the forests of southern Ghana and western Togo. During two surveys in 2005 (Ghana) and 2007 (Ghana and Togo), we recorded at least 45 frog species. These included first country records for Ghana (Kassina cf. cochranae) and Togo (Hyperolius sylvaticus sylvaticus), and several species that had not or only rarely been found after they had been described, e.g. we herein report the rediscovery of Conraua derooi. A high percentage of the recorded frog assemblages consisted of species endemic to the Upper Guinea forest, to Ghana or even a particular region within Ghana (and Togo). The majority of species was closely associated with forest habitats. Nevertheless, in some forest areas the presence of savanna and farmbush species indicated serious habitat degradation. This situation was particularly obvious in the Togo-Volta Highlands. The fact that one third of the encountered amphibians were threatened highlights the importance of the forest ecosystems of southern Ghana and western Togo for the maintenance of the regional biodiversity. However, our results also indicate the urgent need to protect these forests more efficiently (© 2009 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim)

A new medium-sized Phrynobatrachus species from primary forest in south-western Ghana is described. Phrynobatrachus intermedius sp. nov. exhibits a combination of unique morphological and color characters including: compact body, short and pointed snout, a conspicuous dark face mask that covers the loreal and the tympanal area, a relatively smooth dorsum with only very feebly developed dorsal ridges, a black throat with few small white spots, a breast with blackish vermiculation, and moderately developed webbing. Furthermore, the analysis of mitochondrial 16S rRNA revealed that this new species differs from other West African species of the genus by a minimum distance of 3.4%. The new species is morphologically most similar to P. liberiensis (genetic distance 3.4–5.8 %) and P. plicatus (> 10% difference in the 16S rRNA fragment examined). P. liberiensis from the type locality of the new species are genetically more distant to the new species than those from other West African localities.

Africa is renowned for its biodiversity and endemicity, yet little is known about the factors shaping them across the continent. African Agama lizards (45 species) have a pan-continental distribution, making them an ideal model for investigating biogeography. Many species have evolved conspicuous sexually dimorphic traits, including extravagant breeding coloration in adult males, large adult male body sizes, and variability in social systems among colorful versus drab species. We present a comprehensive time-calibrated species tree for Agama, and their close relatives, using a hybrid phylogenetic-phyloge- nomic approach that combines traditional Sanger sequence data from five loci for 57 species (146 sam- ples) with anchored phylogenomic data from 215 nuclear genes for 23 species. The Sanger data are analyzed using coalescent-based species tree inference using * BEAST, and the resulting posterior distribu- tion of species trees is attenuated using the phylogenomic tree as a backbone constraint. The result is a time-calibrated species tree for Agama that includes 95% of all species, multiple samples for most species, strong support for the major clades, and strong support for most of the initial divergence events. Diver- sification within Agama began approximately 23 million years ago (Ma), and separate radiations in South- ern, East, West, and Northern Africa have been diversifying for >10 Myr. A suite of traits (morphological, coloration, and sociality) are tightly correlated and show a strong signal of high morphological disparity within clades, whereby the subsequent evolution of convergent phenotypes has accompanied diversifi- cation into new biogeographic areas.

Because tropical forests face serious threats and are usually situated in developing countries, cheap and easy Rapid Biodiversity Assessment (RBA) seems an ideal strategy for documenting changes in habitat quality and setting conservation priorities. Fruit-feeding butterflies are often used as focal taxa to document biodiversity trends in tropical forests. However, the choice of inappropriate sampling strategies may nullify its value. More extensive data sets that sample multiple months and seasons and incorporate the vertical dimension are needed as a baseline for designing reliable sampling regimes. Therefore, we performed a butterfly trapping study in Ghana, using both understorey and canopy traps, and sampling seven periods covering dry and wet seasons. Both individual numbers and species richness were on average three to four times higher in the understorey than in the canopy traps with strikingly different species composition (only 11% overlap in species). The number of species and individual abundance recorded in a month varied extensively. This study underlined the importance of taking into account temporal variation and vertical stratification when designing RBAs of fruit-feeding butterflies in West African forests. We recommend the use of both understorey and canopy traps and inclusion of both ‘wet’ and ‘dry’ seasons into RBA sampling regimes. Resume Comme les forets tropicales font face a des menaces graves et qu'elles sont en general situees dans des pays en developpement, une evaluation rapide de la biodiversite (RBA) semble une strategie ideale pour documenter les changements de qualite de l'habitat et etablir des priorites de conservation. On se sert souvent des papillons frugivores comme taxons focaux pour documenter les tendances de la biodiversite dans des forets tropicales. Cependant, le choix de strategies d’echantillonnage inappropriees risque d'annuler leur valeur. Il faut des ensembles de donnees plus complets, qui echantillonnent sur des mois et des saisons et qui integrent une dimension verticale pour etablir la base de reference permettant de concevoir des regimes d’echantillonnage fiables. C'est pourquoi nous avons fait une etude de piegeage des papillons au Ghana, en utilisant des pieges en sous-bois et dans la canopee, et en couvrant sept periodes comptant des saisons seches et des saisons des pluies. Aussi bien les chiffres individuels que la richesse en especes etaient en moyenne 3 a 4 fois superieurs dans les pieges places en sous-bois que dans la canopee, avec une composition des especes remarquablement differente (seulement 11% de recouvrement des especes). Le nombre d'especes et l'abondance individuelle enregistres en un mois variaient enormement. Cette etude souligne qu'il est important de prendre en compte la variation temporelle et la stratification verticale lorsque l'on prepare une RBA de papillons frugivores dans des forets d'Afrique de l'Ouest. Nous recommandons l'emploi de pieges en sous-bois et dans la canopee et l'inclusion de saisons « seches » et « humides » dans les regimes d’echantillonnages d'une RBA.

There is a lack of quantitative information on the effectiveness of selective-logging practices in ameliorating effects of logging on faunal communities. We conducted a large-scale replicated field study in 3 selectively logged moist semideciduous forests in West Africa at varying times after timber extraction to assess post logging effects on amphibian assemblages. Specifically, we assessed whether the diversity, abundance, and assemblage composition of amphibians changed over time for forest-dependent species and those tolerant of forest disturbance. In 2009, we sampled amphibians in 3 forests (total of 48 study plots, each 2 ha) in southwestern Ghana. In each forest, we established plots in undisturbed forest, recently logged forest, and forest logged 10 and 20 years previously. Logging intensity was constant across sites with 3 trees/ha removed. Recently logged forests supported substantially more species than unlogged forests. This was due to an influx of disturbance-tolerant species after logging. Simultaneously Simpson's index decreased, with increased in dominance of a few species. As time since logging increased richness of disturbance-tolerant species decreased until 10 years after logging when their composition was indistinguishable from unlogged forests. Simpson's index increased with time since logging and was indistinguishable from unlogged forest 20 years after logging. Forest specialists decreased after logging and recovered slowly. However, after 20 years amphibian assemblages had returned to a state indistinguishable from that of undisturbed forest in both abundance and composition. These results demonstrate that even with low-intensity logging (≤3 trees/ha) a minimum 20-year rotation of logging is required for effective conservation of amphibian assemblages in moist semideciduous forests. Furthermore, remnant patches of intact forests retained in the landscape and the presence of permanent brooks may aid in the effective recovery of amphibian assemblages.

Arthroleptis krokosua Ernst, Agyei & Rödel, 2008 is a recently described, morphologically distinct squeaker species. It has no apparent affiliations to any other West African member of the genus (Ernst et al. 2008), but instead is most closely related to some Central African Arthroleptis (Blackburn et al. 2010). It differs from all known West African Arthroleptis by its large size (> 40 mm snout-vent-length), coloration and other morphological characters, such as a very broad head. Until now the species is only known from the type locality, the Krokosua Hills Forest Reserve and only from the holotype (Ernst et al. 2008). Other large Arthroleptis (larger than 35 mm SVL) are known from Central and East Africa (Blackburn et al. 2009). As A. krokosua might be locally endemic, i.e. amphibian assessments in other Ghanaian and eastern Ivorian forests failed to detect this species (Hillers et al. 2009 and literature cited therein); we herein aim to add more data on the variability, distribution and ecology of A. krokosua.