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The Riverine Barriers Hypothesis (RBH) posits that tropical rivers can be effective barriers to gene flow, based on observations that range boundaries often coincide with river barriers. Over the last 160 years, the RBH has received attention from various perspectives, with a particular focus on vertebrates in the Amazon Basin. To our knowledge, no molecular assessment of the RBH has been conducted on birds in the Afrotropics, despite its rich avifauna and many Afrotropical bird species being widely distributed across numerous watersheds and basins. Here, we provide the first genetic evidence that an Afrotropical river has served as a barrier for birds and for their lice, based on four understory bird species collected from sites north and south of the Congo River. Our results indicate near-contemporaneous, Pleistocene lineage diversification across the Congo River in these species. Our results further indicate differing levels of genetic variation in bird lice; the extent of this variation appears linked to the life-history of both the host and the louse. Extensive cryptic diversity likely is being harbored in Afrotropical forests, in both understory birds and their lice. Therefore, these forests may not be “museums” of old lineages. Rather, substantial evolutionary diversification may have occurred in Afrotropical forests throughout the Pleistocene, supporting the Pleistocene Forest Refuge Hypothesis. Strong genetic variation in birds and their lice within a small part of the Congo Basin forest indicates that we may have grossly underestimated diversity in the Afrotropics, making these forests home of substantial biodiversity in need of conservation.

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Résumé.-Nous décrivons ici Laniarius willardi, une nouvelle espèce de la famille des Malaconotidae vivant au Rift Albertine, en Afrique. Le caractère morphologique le plus remarquable de cette espèce est un iris gris à bleu-gris. Ceci et des données morphométriques externes indiquent que L. willardi est différent des autres Laniarius. De plus, L. willardi est génétiquement différent et son plus proche parent est L. poensis camerunensis, au Cameroun. L. atrococcineus et L. leucorhynchus forment le clade saeur de L. willardi-L. p. camerunensis. L. willardi et L. p. holomelas, dont la répartition géographique est similaire, diffèrent de , % en ce qui concerne la divergence de la séquence corrigée. Les données altitudinales récoltées sur des spécimens de musée suggèrent qu'il existe une possibilité de ségrégation altitudinale des espèces à ~  m, L. willardi étant présent à des altitudes plus faibles. Notre vaste échantillonnage de ce taxon indique que () les races L. poensis ne forment pas un clade monophylétique, () L. p. camerunensis peut représenter des lignées multiples qui ne sont pas saeurs et () au moins une race de L. fuelleborni usambaricus est génétiquement distincte des autres races de cette espèce.-678 - In , T.P.G., C.K., and B.D.M. conducted collections-based field work in the southern region of Uganda, in the Albertine Rift system. Their survey was conducted on privately held property primarily used as a banana plantation, which included the only forest contiguous with the Bwindi Impenetrable National Park in the area. During this survey, they collected  black Laniarius specimens that they were forced to attribute to L. poensis holomelas on the basis of size and plumage characteristics. However, these specimens, and an additional Field Museum of Natural History (FMNH) specimen collected in Burundi in , were noted as having a unique iris color (gray to blue-gray) unlike that shown for any black Laniarius species in field guides (reddish-black to black). We could find no published reports describing blue-gray irides in adults of black Laniarius species, which reinforced concerns about the identification of these specimens (Marks et al. ).Further questions related to species limits and taxonomy of black Laniarius species are raised by the broader distributions of L. poensis and L. fuelleborni. The former has a significant geographic disjunction between subspecies in the Albertine Rift and Mt. Cameroon (Fig. ), and the latter has populations isolated on different mountains of the Eastern Arc, as well as a population in southwestern Tanzania and northern Malawi (Fry et al. ). Taxonomically, these two species have been linked; races of L. poensis were historically recognized as subspecies of L. fuelleborni (Mayr and Greenway ). Also, L. poensis and L. fuelleborni along with L. leucorhynchus are considered a superspecies (Fry et al. ). However, no phylogenetic study has addressed the relationships among these populations.We had two goals in the present study. First, we con...

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The endangered warbler Bradypterus graueri is endemic to the Albertine Rift, where it is restricted to montane swamps above 1900 m across the region. We studied genetic structure among six populations sampled across the species' distribution in northern Burundi, Rwanda, Uganda and the eastern Democratic Republic of Congo. A total of 2117 base pairs of mitochondrial data were sequenced. Phylogenetic analyses and network reconstruction of B. graueri haplotypes recovered three clades with a defined geographical pattern: clade 1, Virunga Volcanoes and Kigezi Highlands; clade 2, Rugege Highlands; and clade 3, Kahuzi‐Biega Highlands; clades 2 and 3 are sisters to each other. Both landscape dynamics and historical climate are likely to have played a role in the diversification of this species. The divergence between clade 1 and clades 2 and 3 (168.5 ka, 95% HPD 108.5, 244.4) coincides with a prolonged period of aridity in tropical Africa between 130 and 270 ka. Similarly, the divergence between clades 2 and 3 (99.4 ka, 95% HPD 55.4, 153.8) corresponds with a period of aridity just prior to 94 ka. Populations sampled from the eastern arm of the central Albertine Rift (Kigezi and Rugege Highlands) show a coincident increase in effective population size after the Last Glacial Maximum at c. 15 ka, whereas those sampled from Kahuzi‐Biega on the western arm of the rift do not. Despite the perceived higher vagility of bird species relative to other vertebrates, the degree of phylogeographical structure among populations of B. graueri is similar to that reported for small mammals (Hylomyscus vulcanorum, Lophuromys woosnami, Sylvisorex vulcanorum) and a frog Hyperolius castaneus sampled across the central Albertine Rift. Collectively our results suggest that climate dynamics associated with late Pleistocene cycles had a significant influence on driving the population genetic structure and associated levels of genetic diversity in B. graueri and other small terrestrial vertebrates. Our results have implications for the conservation of B. graueri and other endemics to the Albertine Rift, particularly in the context of other phylogegeographical studies centred on this biodiversity hotspot.

A l’instar de nombreuses autres forêts des montagnes non protégées, la forêt de Burhinyi, faisant partie du massif d’Itombwe, subit une forte pression due aux activités humaines qui impactent négativement la valeur globale du site. Nous avons évalué les connaissances et l’impact de certaines pratiques des populations riveraines de la forêt de Burhinyi sur la conservation de l’avifaune en vue d’obtenir les données de base susceptibles d’orienter les initiatives de conservation communautaire en cours. Un questionnaire d’enquête a été utilisé pour collecter les données auprès de 188 personnes issues des différents ménages choisis dans 6 villages. Cette étude révèle que les populations riveraines exercent un bon nombre d’activités ayant un effet néfaste sur la biodiversité forestière. Il s’agit notamment des techniques de chasse, des pratiques agricoles et de l’exploitation minière. Sur 22 taxons couramment abattus à Burhinyi, une moyenne de 4,6 oiseaux est tuée journalièrement. Six taxa (Aigles, Hiboux, Corbeaux, Buses montagnardes, Gonoleks et Touracos) sont exploités en médecine traditionnelle et comme ornement des tenues portées par les chefs locaux pendant les cérémonies coutumières. Les connaissances des populations riveraines sur l’avifaune sont larges. Toutefois, elles sont significativement variables selon le groupement d’origine mais pas selon le niveau d’études. L’importance de la conservation des oiseaux a été reconnue par 80,1% des enquêtés contre 14,5% qui s’y opposent et 0,5% d’indécis.Mots clés : Perception, communautés, protection, oiseaux, Rift Albertin.   English Title: Assessment of knowledge and impact of practices by riparian populations of Burhinyi Forest (Itombwe, South-Kivu, DR Congo) on the conservation of avifauna Like many other unprotected mountain forests, the Burhinyi forest is under great pressure due to human activities, which negatively impact the global value of the site. We assessed the knowledge and impact of some practices within riparian populations around Burhinyi forest on the conservation of avifauna to obtain baseline data that could guide ongoing community conservation initiatives. A survey questionnaire was used to collect data from 188 people from households selected in 6 villages. This study shows that riparian populations are engaged in a number of activities that have a negative impact on forest biodiversity. These include hunting techniques, agricultural practices and mining. Of the 22 taxa commonly trapped in Burhinyi, an average of 4.6 birds are killed daily. Six taxa (Eagles, Owls, Ravens, Mountain Hawks, Gonoleks and Touracos) are used in traditional medicine and sources of ornaments of attires worn by local leaders during customary ceremonies. The knowledge of the riparian populations about the avifauna is broad. However, they vary significantly by area of origin and not by education level. The importance of bird conservation was recognized by 80.1% of respondents compared with 14.5% who opposed it and 0.5% who were undecided.Keywords : Perception, communities, protection, birds, Albertine Rift.

Barred Long‐tailed Cuckoo (Cercococcyx montanus) currently comprises two morphologically distinct subspecies, one resident in the Albertine Rift (montanus) and one in east and southeast Africa (patulus) in which there are migrations that are poorly understood. Based on nuclear and mitochondrial DNA sequences, we find that two specimens collected in relatively low‐elevation forest in the Albertine Rift were correctly identified from plumage as the migratory subspecies whose closest known breeding area is > 800 km to the east. We discuss ways in which this unique migratory pattern could have evolved and argue that migration was gained and then lost in the C. montanus complex. Based on consistent morphological and genetic differences, we suggest that Barred Long‐tailed Cuckoo is best treated as two species, one of which (C. montanus) is a non‐migratory Albertine Rift endemic.