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The avifauna of Cabinda Province, Angola, is poorly known; since 1885 only one ornithological expedition has been made to the province, by AA da Rosa Pinto in 1969. All previous works that include Cabinda, including those of Rosa Pinto, were confined to the coastal and central zones (Lower Mayombe), with the higher-altitude eastern zone (Upper Mayombe) completely unexplored. With access to Cabinda recently improved, we made four short field trips (in 18–21 March 2022, 15–17 June 2022, 23–27 September 2022, and 3–10 June 2023), focused mainly on the Upper Mayombe area, as part of an ongoing effort to make biological inventories for poorly known regions of Angola, which include Mayombe National Park. We recorded 256 bird species: 101, 139, 157 and 187 during Visits 1–4, respectively. Among these were 23 new species records for Angola, most of which were either sound recorded or photographed as evidence. A further 11 species were new to Cabinda but had previously been recorded elsewhere in Angola, and an additional 34 species had previously been recorded fewer than ten times from Angola. These records highlight the biological importance of Mayombe National Park and its significant contribution to the overall biodiversity of Angola. [ABSTRACT FROM AUTHOR]

Endemism is one of the most important concepts in biogeography and is often used to guide biodiversity conservation, yet our understanding of the determinants of endemism in many biodiverse tropical regions is limited. This is true for western Central Africa, a region with one of the highest levels of plant diversity in tropical Africa, where endemism is poorly documented. This study examines the Gabonese Area of Endemism (GAE) and explores the main characteristics and determinants of its vascular plant endemism with regard to taxonomy, growth form, habitat, distribution, and range size. We compiled a comprehensive, verified specimen database of vascular plant taxa restricted to the GAE, comprising 19,876 occurrences of 1145 species and infraspecific taxa, and we characterized the habitat and habit for each taxon. We then calculated the proportion of taxa in the regional flora that are endemic to the GAE. A Wilcoxon rank-sum test was used to investigate range size among endemic taxa exhibiting different growth forms, and Fisher exact tests were used to explore the association between their habit and habitat, and to test the distribution of these attributes among higher-level taxa and growth forms compared to patterns in the regional flora as a whole. We found that endemic taxa represent ca. 13% of the GAE flora, and that the rate of endemism varies considerably among taxonomic groups and growth forms. Endemism is highest among shrubs (22%) and lowest in herbs (8%), especially monocotyledons (e.g., 5% among Poales). Most endemic taxa grow preferentially in forest habitats, the dominant vegetation type of the region. Endemic trees, which structure forest ecosystems, have significantly larger ranges than endemic herbs, climbers, and shrubs. About 17% of the flora of Gabon is endemic or subendemic to the country. Our results show that the dispersal capacity of taxa and the biogeographical history of the region appear to be critical factors in explaining differences in the rate of endemism among growth forms and taxonomic groups. Our findings also highlight the benefits of carefully building a comprehensive and verified database for studying rare and range-restricted plants, and they underscore the necessity to strengthen botanical exploration throughout western Central Africa in order to develop improved and better-informed conservation strategies. [ABSTRACT FROM AUTHOR]

Background and aims – The intensive botanical prospections carried out in Gabon since the publication of the national checklist in 2006 have resulted in c. 34 300 new specimens (amounting to 30% of all collections made in the country) and an annual increase of 25 species in average. As a result, 5175 species of vascular plants are now recorded from Gabon, of which 650 are considered endemic. However, most of the recent discoveries have not yet been published. This paper is the first of a series documenting additions to the flora of Gabon, and new records of poorly known species. It concerns specifically new records from the Lower Ogooué Ramsar site, the third largest delta of Africa, and certainly the most intact, which includes 80% of the country’s wetlands and a wide variety of other habitats.Methods – The new records presented here come essentially from fieldwork conducted in Gabon between 2008 and 2016 by the authors and colleagues. Further information comes from the study of herbarium specimens in BR, BRLU, K, LBV, MO, P and WAG. For each species, information on distribution and ecology is given, and the studied Gabonese collections listed. In case of rare or range-restricted species, collections from other countries are also listed, and a distribution map is provided, as well as an evaluation of the conservation status based on the categories and criteria of the IUCN Red List.Key results – We report 18 additions to the flora of Gabon, including four genera new to the country (Capparis, Gisekia, Hoffmanniella and Leptochloa) and the first records of the neotropical Justicia secunda being naturalised in tropical Africa. New distribution records are also provided for 16 rare Gabonese endemics or near-endemics. Some species are also newly reported from Cameroon (Cissus leemansii, Salacia coronata) and Equatorial Guinea (Cissus leemansii, C. louisii, Lychnodiscus grandifolius, Placodiscus resendeanus, Rutidea gabonensis, Uvaria bipindensis). Two species, which were reported in the 2006 checklist based on misidentifications, are excluded from the Gabonese flora.

A new species of the chromidotilapiine genus Thysochromis, is described from the Noumbi and Kouilou River drainages in the Republic of Congo. Based on the current investigation, Thysochromis is resolved as containing two geographically disjunct species, T. ansorgii from localities in the upper Guinean ichthyofaunal province (Ivory Coast, Ghana, Benin and Nigeria) and Thysochromis emili sp. nov. restricted to coastal regions of the Republic of Congo in the lower Guinean province. [ABSTRACT FROM AUTHOR]

Background and aims - The intensive botanical prospections carried out in Gabon since the publication of the national checklist in 2006 have resulted in c. 34 300 new specimens (amounting to 30% of all collections made in the country) and an annual increase of 25 species in average. As a result, 5175 species of vascular plants are now recorded from Gabon, of which 650 are considered endemic. However, most of the recent discoveries have not yet been published. This paper is the first of a series documenting additions to the flora of Gabon, and new records of poorly known species. It concerns specifically new records from the Lower Ogooué Ramsar site, the third largest delta of Africa, and certainly the most intact, which includes 80% of the country's wetlands and a wide variety of other habitats. Methods - The new records presented here come essentially from fieldwork conducted in Gabon between 2008 and 2016 by the authors and colleagues. Further information comes from the study of herbarium specimens in BR, BRLU, K, LBV, MO, P and WAG. For each species, information on distribution and ecology is given, and the studied Gabonese collections listed. In case of rare or range-restricted species, collections from other countries are also listed, and a distribution map is provided, as well as an evaluation of the conservation status based on the categories and criteria of the IUCN Red List. Key results - We report 18 additions to the flora of Gabon, including four genera new to the country (Capparis, Gisekia, Hoffmanniella and Leptochloa) and the first records of the neotropical Justicia secunda being naturalised in tropical Africa. New distribution records are also provided for 16 rare Gabonese endemics or near-endemics. Some species are also newly reported from Cameroon (Cissus leemansii, Salacia coronata) and Equatorial Guinea (Cissus leemansii, C. louisii, Lychnodiscus grandifolius, Placodiscus resendeanus, Rutidea gabonensis, Uvaria bipindensis). Two species, which were reported in the 2006 checklist based on misidentifications, are excluded from the Gabonese flora. [ABSTRACT FROM AUTHOR]

Abstract: Aim: To investigate how putative barriers, forest refugia, and ecological gradients across the lower Guineo‐Congolian rain forest shape genetic and phenotypic divergence in the leaf‐folding frog Afrixalus paradorsalis, and examine the role of adjacent land bridge and sky‐islands in diversification. Location: The Lower Guineo‐Congolian Forest, the Cameroonian Volcanic Line (CVL), and Bioko Island, Central Africa. Taxon: Afrixalus paradorsalis (Family: Hyperoliidae), an African leaf‐folding frog. Methods: We used molecular and phenotypic data to investigate diversity and divergence among the A. paradorsalis species complex distributed across lowland rain forests, a land bridge island, and mountains in Central Africa. We examined the coincidence of population boundaries, landscape features, divergence times, and spatial patterns of connectivity and diversity, and subsequently performed demographic modelling using genome‐wide SNP variation to distinguish among divergence mechanisms in mainland (riverine barriers, forest refugia, ecological gradients) and land bridge island populations (vicariance, overwater dispersal). Results: We detected four genetically distinct allopatric populations corresponding to Bioko Island, the CVL, and two lowland rain forest populations split by the Sanaga River. Although lowland populations are phenotypically indistinguishable, pronounced body size evolution occurs at high elevation, and the timing of the formation of the high elevation population coincides with mountain uplift in the CVL. Spatial analyses and demographic modelling revealed population divergence across mainland Lower Guinea is best explained by forest refugia rather than riverine barriers or ecological gradients, and that the Bioko Island population divergence is best explained by vicariance (marine incursion) rather than overseas dispersal. Main conclusions: We provide growing support for the important role of forest refugia in driving intraspecific divergences in the Guineo‐Congolian rain forest. In A. paradorsalis, sky‐islands in the CVL have resulted in greater genetic and phenotypic divergences than marine incursions of the land bridge Bioko Island, highlighting important differences in patterns of island‐driven diversification in Lower Guinea. [ABSTRACT FROM AUTHOR]

The accumulation of biodiversity in tropical forests can occur through multiple allopatric and parapatric models of diversification, including forest refugia, riverine barriers and ecological gradients. Considerable debate surrounds the major diversification process, particularly in the West African Lower Guinea forests, which contain a complex geographic arrangement of topographic features and historical refugia. We used genomic data to investigate alternative mechanisms of diversification in the Gaboon forest frog, Scotobleps gabonicus, by first identifying population structure and then performing demographic model selection and spatially explicit analyses. We found that a majority of population divergences are best explained by allopatric models consistent with the forest refugia hypothesis and involve divergence in isolation with subsequent expansion and gene flow. These population divergences occurred simultaneously and conform to predictions based on climatically stable regions inferred through ecological niche modelling. Although forest refugia played a prominent role in the intraspecific diversification of S. gabonicus, we also find evidence for potential interactions between landscape features and historical refugia, including major rivers and elevational barriers such as the Cameroonian Volcanic Line. We outline the advantages of using genomewide variation in a model-testing framework to distinguish between alternative allopatric hypotheses, and the pitfalls of limited geographic and molecular sampling. Although phylogeographic patterns are often species-specific and related to life-history traits, additional comparative studies incorporating genomic data are necessary for separating shared historical processes from idiosyncratic responses to environmental, climatic and geological influences on diversification. [ABSTRACT FROM AUTHOR]

Aim We sought to test the refuge hypothesis as a major driver of genetic differentiation to explain the development of distinct phytogeographical domains in tropical Central African rain forest. To address this aim, we studied the phylogeographical pattern of a pair of sister plant species, Haumania danckelmaniana and H. liebrechtsiana (Marantaceae), distributed across the two phytogeographical domains: Lower Guinea and Congolia. Location Tropical Central Africa including the phytogeographical domains Lower Guinea and Congolia. Methods Seven polymorphic microsatellite loci were genotyped in a total of 513 individuals from both species. The dataset was analysed for population genetic structure and demographic change and the results compared to the geographical pattern of plastid DNA sequences from a previous publication and other sympatric species. Results Based on the microsatellite dataset, three distinct homogeneous genetic clusters were detected in H. danckelmaniana and two in H. liebrechtsiana. These clusters corresponded geographically with the patterns found in the plastid DNA sequences. Genetic diversity and endemism were unevenly distributed between clusters in the two species. Most clusters exhibited signals of population expansion. Main conclusions The phylogeographical data based on microsatellites and plastid DNA revealed a complex history involving (1) allopatric differentiation with each species originating in a different phytogeographical domain, potentially resulting from past forest fragmentation, followed by (2) population expansion and interspecific introgression, which probably occurred during a phase of forest expansion. Moreover, phylogeographical patterns within each species provided evidence of (3) past population fragmentation followed by partial population admixture in H. danckelmaniana, and deep differentiation between Lower Guinea and Congolia in H. liebrechtsiana. The observed patterns were globally consistent with the refuge hypothesis and the presented scenario illustrates evolutionary processes that likely have contributed to shaping the African phytogeographical domains. [ABSTRACT FROM AUTHOR]

Vegetation history in tropical Africa is still to date hardly known and the drivers of population differentiation and speciation processes are little documented. It has often been postulated that population fragmentations following climate changes have played a key role in shaping the geographic distribution patterns of genetic diversity and in driving speciation. Here we analyzed phylogeographic patterns (chloroplast-DNA sequences) within and between eight (sister) species of widespread rainforest herbs and lianas from four genera of Marantaceae (Halopegia, Haumania, Marantochloa, Megaphrynium), searching for concordant patterns across species and concordance with the Pleistocene refuge hypothesis. Using 1146 plastid DNA sequences sampled across African tropical lowland rainforest, particularly in the Lower Guinean (LG) phytogeographic region, we analyzed intra- and interspecific patterns of genetic diversity, endemism and distinctiveness. Intraspecific patterns of haplotype diversity were concordant among most species as well as with the species-level diversity pattern of Marantaceae. Highest values were found in the hilly areas of Cameroon and Gabon. However, the spatial distribution of endemic haplotypes, an indicator for refuge areas in general, was not congruent across species. Each proposed refuge exhibited high values of endemism for one or a few species indicating their potential role as area of retraction for the respective species only. Thus evolutionary histories seem to be diverse across species. In fact, areas of high diversity might have been both refuge and/or crossing zone of recolonization routes i.e. secondary contact zone.We hypothesize that retraction of species into one or the other refuge happened by chance depending on the species´ distribution range at the time of climate deterioration. The idiosyncratic patterns found in Marantaceae species are similar to those found among tropical tree species, especially in southern LG.

This paper summarizes current knowledge about Central African pholcids. Central Africa is here defined as the area between 10°N and 7°S and between 6°E and 18°E, including mainly the Lower Guinean subregion of the Guineo-Congolian center of endemism. This includes all of Gabon, Equatorial Guinea, São Tomé and Príncipe, most of Cameroon and Congo Republic, and parts of the neighboring countries. An annotated list of the 14 genera and 79 species recorded from this area is given, together with distribution maps and an identification key to genera. Seven species are newly described: Anansus kamwai sp. nov., Leptopholcus gabonicus sp. nov., Ninetis faro sp. nov., Pholcus punu sp. nov., P. rawiriae sp. nov., Spermophora abibae sp. nov., and S. awalai sp. nov. Additional new records are given for 16 previously described species, including 17 new country records. Distribution and diversity patterns are compared with data on West and East Africa. While West Africa contains a similar set of genera it is significantly less diverse than Central Africa. East Africa is taxonomically more distinct. It has similar levels of diversity as Central Africa, but appears to be less undersampled.

Evidence of sexual dimorphism in body size and the existence of morphological differences were studied in the yellow-whiskered Greenbul Andropadus latirostris. We measured fresh body weight and seven linear parameters of external morphology in mature individuals of this species from three localities in Cameroon and two localities in Ghana. Based on general linear model analysis, we showed that males are significantly larger than females. We applied a discriminant analysis on eight morphometric parameters to create two discriminant functions, one for each country. The overall rate of well-classified birds was 93.3% for Cameroon and 92.7% for Ghana. Wing length was the most accurate character for separating the sexes in both study areas. Significant sexual size dimorphism might be explained by sexual selection on male competitive ability and intraspecific competition. We also found morphological divergence in this species between the two study areas, including marked differences in size of the beak. This work provides statistical evidence of a substantial sexual size dimorphism in A. latirostris and geographic variation in morphology. [ABSTRACT FROM AUTHOR]

Vegetation history in tropical Africa is still to date hardly known and the drivers of population differentiation and speciation processes are little documented. It has often been postulated that population fragmentations following climate changes have played a key role in shaping the geographic distribution patterns of genetic diversity and in driving speciation. Here we analyzed phylogeographic patterns (chloroplast-DNA sequences) within and between eight (sister) species of widespread rainforest herbs and lianas from four genera of Marantaceae (Halopegia, Haumania, Marantochloa, Megaphrynium), searching for concordant patterns across species and concordance with the Pleistocene refuge hypothesis. Using 1146 plastid DNA sequences sampled across African tropical lowland rainforest, particularly in the Lower Guinean (LG) phytogeographic region, we analyzed intra- and interspecific patterns of genetic diversity, endemism and distinctiveness. Intraspecific patterns of haplotype diversity were concordant among most species as well as with the species-level diversity pattern of Marantaceae. Highest values were found in the hilly areas of Cameroon and Gabon. However, the spatial distribution of endemic haplotypes, an indicator for refuge areas in general, was not congruent across species. Each proposed refuge exhibited high values of endemism for one or a few species indicating their potential role as area of retraction for the respective species only. Thus, evolutionary histories seem to be diverse across species. In fact, areas of high diversity might have been both refuge and/or crossing zone of recolonization routes i.e., secondary contact zone. We hypothesize that retraction of species into one or the other refuge happened by chance depending on the species' distribution range at the time of climate deterioration. The idiosyncratic patterns found in Marantaceae species are similar to those found among tropical tree species, especially in southern LG. [ABSTRACT FROM AUTHOR]

Cycles of Quaternary climatic change are assumed to be major drivers of African rainforest dynamics and evolution. However, most hypotheses on past vegetation dynamics relied on palaeobotanical records, an approach lacking spatial resolution, and on current patterns of species diversity and endemism, an approach confounding history and environmental determinism. In this context, a comparative phylogeographical study of rainforest species represents a complementary approach because Pleistocene climatic fluctuations may have left interpretable signatures in the patterns of genetic diversity within species. Using 1274 plastid DNA sequences from eight tree species ( Afrostyrax kamerunensis, A. lepidophyllus, Erythrophleum suaveolens, Greenwayodendron suaveolens, Milicia excelsa, Santiria trimera, Scorodophloeus zenkeri and Symphonia globulifera) sampled in 50 populations of Atlantic Central Africa ( ACA), we averaged divergence across species to produce the first map of the region synthesizing genetic distinctiveness and standardized divergence within and among localities. Significant congruence in divergence was detected mostly among five of the eight species and was stronger in the northern ACA. This pattern is compatible with a scenario of past forest fragmentation and recolonization whereby forests from eastern Cameroon and northeastern Gabon would have been more affected by past climatic change than those of western Cameroon (where one or more refugia would have occurred). By contrast, southern ACA (Gabon) displayed low congruence among species that may reflect less drastic past forest fragmentation or a more complex history of vegetation changes. Finally, we also highlight the potential impact of current environmental barriers on spatial genetic structures. [ABSTRACT FROM AUTHOR]

Abstract: The biogeographic history of the African rain forests has been contentious. Phylogeography, the study of the geographic distribution of genetic lineages within species, can highlight the signatures of historical events affecting the demography and distribution of species (i.e. population fragmentation or size changes, range expansion/contraction) and, thereby, the ecosystems they belong to. The accumulation of recent data for African rain forests now enables a first biogeographic synthesis for the region. In this review, we explain which phylogeographic patterns are expected under different scenarios of past demographic change, and we give an overview of the patterns detected in African rain forest trees to discuss whether they support alternative hypotheses regarding the history of the African rain forest cover. The major genetic discontinuities in the region support the role of refugia during climatic oscillations, though not necessarily following the classically proposed scenarios. We identify in particular a genetic split between the North and the South of the Lower Guinean region. Finally we provide some perspectives for future study. [Copyright &y& Elsevier]

Garcinia has some 260 species and is often regarded as a genus with a difficult taxonomy. No recent treatment is available for the botanically rich Lower Guinea phytogeographical region. This study aims at partly filling this gap. First, several taxonomic problems are solved. G. chromocarpa is reduced to a variety of G. quadrifaria. G. gnetoides and G. granulata are both synonyms of G. quadrifaria. G. zenkeri is a synonym of G. densivenia and lectotypes are being designated for both names. G. brevipedicellata is a synonym of G. afzelii, as is G. antidysenterica for which a lectotype is designated. Second, two new species endemic to Gabon are described: Garcinia gabonensis Sosef & Dauby and Garcinia obliqua Sosef & Dauby. Finally, an identification key to all species present in the Lower Guinea region is provided. A few remaining West African species names could not be placed with certainty, because the type material was lost or not traced yet. One is a Rutaceae while the remaining three are provisionally to be regarded as synonyms of G. smeathmannii. [ABSTRACT FROM AUTHOR]

A taxonomic revision of the palm genus Podococcus ( Arecaceae) is presented. Two species are recognised: P. barteri, a species relatively widespread in a coastal band from Nigeria to the D. R. Congo and P. acaulis, a species previously considered conspecific to P. barteri, almost exclusively confined to Gabon. The taxonomic history, morphology, distribution and conservation status of the genus and each species are discussed [ABSTRACT FROM AUTHOR]

A taxonomic revision of the palm genus Sclerosperma ( Arecaceae) is presented. Three species are recognised: S. mannii H. Wendl., which is relatively widespread from Liberia to the Democratic Republic of Congo; S. walkeri A. Chev., which is apparently confined to the interior of Gabon and a band along the Congo River; and S. profiziana, a new species previously considered conspecific to S. mannii that is found in southwest Ghana, Congo, the Democratic Republic of Congo and Angola. The taxonomic history, morphology, distribution and conservation status of the genus and each species are discussed. [ABSTRACT FROM AUTHOR]