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SummaryWe describe two range-restricted new species to science from the genus Impatiens (Balsaminaceae), both threatened, from lowland of the Cross-Sanaga Interval of western Cameroon. The first, Impatiens banen, appears to be restricted to an open seepage microhabitat on granitic inselbergs in the lowland-submontane forest zone of the Ebo Forest in Littoral Region and is provisionally assessed using the 2012 IUCN standard as Vulnerable. Sharing characters with Impatiens burtonii and I. mannii, it differs from both, and appears to be unique in Cameroon inter alia 1) in the bicolored united lateral petals, the upper petals being white, while the lower petals are an intense pink-purple, 2) the hairy, filamentous spur, purple with a white apex, is curved along its length, almost describing a circle. Inselberg-specific species are unusual in Impatiens.The second species, Impatiens etugei, of the I. macroptera aggregate, is restricted to rocks in the Mutel River of the Kom Wum Forest Reserve of North West Region and is assessed as Critically Endangered. Having similarities with I. mackeyana and I. letouzeyi, it differs from other species in the aggregate inter alia by having opposite leaves (vs always alternate), flower exterior white (vs pink or pink-purple), and in the dorsal petal having a pair of lateral projections (vs projections absent).

SummaryWe revise and update the records of strict and near-endemic species of the Bali Ngemba Forest Reserve, the largest known surviving patch (c. 8 km2 in area) of submontane or cloud forest in the Bamenda Highlands, Cameroon which have lost >96 % of their original forest due to human activities. Nine strict endemics, and 11 near endemics are now documented, a drop from the number recorded after the first survey in 2004, since when five of the provisionally named species have been validly published. We test the hypothesis that a further one of the provisionally named putative Bali Ngemba new species, Vepris sp. A, an 8 – 20 m tall tree from cloud forest in the 1310 – 1700 m altitudinal band, is indeed new to science. We compare it morphologically with other multicarpellate, apocarpous, trifoliolate Cameroon tree species formerly placed in the genus Oricia Pierre until they were subsumed into Vepris by Mziray (1992). These are V. trifoliolata (Engl.) Mziray and V. gabonensis (Pierre) Mziray. We conclude that Vepris sp. A is a new undescribed species here named as Vepris onanae. The new species is illustrated, mapped and its conservation status assessed as Critically Endangered using the 2012 IUCN standard due to severe fragmentation and the threats of habitat clearance from agricultural pressures at its three locations all of which remain formally unprotected. Vepris onanae appears unique among the Guineo-Congolian African oricioid species of Vepris in that it occurs in cloud forest, the other species, apart from V. renieri (G.C.C.Gilbert) Mziray of the Albertine Rift, occurring in lowland forest. It also differs in the very broad, (7.8 –) 11.3 – 18 cm wide leaflets of the flowering stems which have a 6 – 18 (– 30) mm long, narrowly triangular acumen (vs leaflets Vepris and characterise a level of sexual dimorphism more advanced than usual in the genus. We highlight the importance of protecting Bali Ngemba and other forest patches in the Bamenda Highlands if species such as Vepris onanae are not soon to become extinct.

The Checklist of the Vascular Plants of the Republic of Guinea (CVPRG) is a specimen-based, expert-validated knowledge product, which provides a concise synthesis and overview of current knowledge on 3901 vascular plant species documented from Guinea (Conakry), West Africa, including their accepted names and synonyms, as well as their distribution and status within Guinea (indigenous or introduced, endemic or not). The CVPRG is generated automatically from the Guinea Collections Database and the Guinea Names Backbone Database, both developed and maintained at the Royal Botanic Gardens, Kew, in collaboration with the staff of the National Herbarium of Guinea. A total of 3505 indigenous vascular plant species are reported of which 3328 are flowering plants (angiosperms); this represents a 26% increase in known indigenous angiosperms since the last floristic overview. Intended as a reference for scientists documenting the diversity and distribution of the Guinea flora, the CVPRG will also inform those seeking to safeguard the rich plant diversity of Guinea and the societal, ecological and economic benefits accruing from these biological resources.

SummaryWe revise and update the records of strict and near-endemic species of Mt Kupe, Cameroon respectively from 31 strict endemics in 2004, to 25 today, and with near-endemic species 30, unchanged in number but with turnover. The changes result from new collections, discoveries and taxonomic changes in the last 16 years. While 15 of the provisionally named putative endemic species have now been formally published, a further 18 have not. The majority of the 30 near-endemic species (18) are shared with the adjacent Bakossi Mts, far exceeding the numbers shared with the more distant Mt Etinde-Mt Cameroon, Rumpi Hills and Ebo forest areas (sharing three near-endemic species each with Mt Kupe). We test the hypothesis that a further one of the provisionally named putative Mt Kupe species,Veprissp. 1 from submontane forest near the summit, is indeed new to science. We compare it morphologically with the two other bicarpellate high altitude Cameroon Highland tree speciesV. montisbambutensisOnana andV. baliCheek, concluding that it is a new undescribed species here named asVepris zapfackii. The new species is illustrated and its conservation status assessed as Critically Endangered using the 2012 IUCN standard, due to habitat clearance from agricultural pressures at its sole location which is unprotected.Vepris zapfackiiandV. baliappear unique in African trifoliolate species of the genus in having opposite leaves.Vepris zapfackiidiffers in having hairy petiolules and midribs and petiolules with the blade decurrent distally, narrowing towards a winged-canaliculate base (vs glabrous and petiolule long, terete), and sparsely golden hairy pistillodes and a glabrous calyx (vs densely black hairy pistillodes, and sepals hairy).

SummaryWe describe Microcos rumpi (Grewiaceae-Malvaceae) as a new species to science from the Rumpi Hills of SW Region Cameroon, a proposed Tropical Important Plant Area. Confined on current evidence to submontane forest, the species is threatened by expanding habitat clearance for farms and is assessed as Critically Endangered. A massive tree, attaining 35 – 40 m height, and 80 cm trunk diameter at 1.3 m above ground, its biomass is calculated as in the range of 7 – 8 metric tonnes. It is the third tree species of the genus recorded from Cameroon and only the fourth recorded west of D.R. Congo. A key to these four species is presented.The concept of Microcos in Africa in relation to Grewia is discussed, and three new combinations are made, transferring three species names from Grewia to Microcos: Microcos louisii (Wilczek) Cheek, M. evrardii(Wilczek) Cheek and M.schmitzii (Wilczek) Cheek.

For millennia, people have harvested fruits from the wild for their alimentation. Gradually, they have started selecting wild individuals presenting traits of interest, protecting and cultivating them. This was the starting point of their domestication. The passage from a wild to a cultivated status is accompanied by a modification of a number of morphological and genetic traits, commonly known as the domestication syndrome. We studied the domestication syndrome in

SummaryMonanthotaxis bali is the only known, solely montane (occurring solely above 2000 m alt.) species of the genus. It joins Monanthotaxis orophila (Rwanda) and M. discolor (Tanzania), two other species that can also occur above 2000 m alt. Monanthotaxis bali is an addition to the small number (28) of the tree species of the surviving montane forests of the Cameroon Highlands of which only eight other species are endemic.Due to its supra-axillary inflorescences, and petals arranged in one whorl but with the outer petals overlapping the inner petals distally, and rounded flower buds, the new species is placed in Hoekstra’s clade B of Monanthotaxis. The new species is unusual in being a treelet in a predominantly lianescent genus, and in lacking the glaucous underside of the leaf-blades that usually characterises the genus. Monanthotaxis bali takes the number of continental African species of the genus to 80, and makes Cameroon, with 30 species, the most species-diverse country for the genus.Monanthotaxis bali is known only from the Bali Ngemba Forest Reserve, a forest remnant under pressure of degradation and clearance in the Bamenda Highlands of Cameroon. It may already be extinct due to logging and agricultural activities. Here it is described, illustrated, mapped and assessed as Critically Endangered (Possibly Extinct) using the IUCN 2012 criteria.

Here we publish a new species of forest tree of the genus Drypetes Vahl (Putranjivaceae), D. umbricola D. J. Harris & Quintanar, which has a wide distribution in Central Africa (Cameroon, Central African Republic, Democratic Republic of the Congo, Gabon, and Republic of the Congo). It is known from 70 herbarium collections and additional sterile plot vouchers. A differential diagnosis, detailed morphological description, photographs, an illustration, and information about its habitat, distribution, and conservation status are provided.

Plant diversity conservation has become one of the most critical objectives of forest management in an ecologically sustainable way. However, biodiversity conservation and sustainable management issues are sometimes neglected in Cameroon's communal forests because their botanical importance, and high-priority species for conservation are poorly known. In the present study, done in the Doume Communal Forest (DCF) situated in eastern Cameroon, we explore its potential in terms of plant diversity as well as conservation value. Forest inventories done in thirty 1-ha plots were analysed using diversity indices, species and family importance values index as well as IUCN conservation status. A total of 22,064 stems with a diameter ≥ 1 cm were recorded within thirty 1-ha sampling plots, belonging to 307 species, 194 genera and 72 families. The DCF is particularly rich in members of the Malvaceae, Annonaceae, Meliaceae and Apocynaceae. The list of the plant species known from the DCF reaches 330 species, with 290 identified at the species level. It was found out that 49 species can be considered high-priority species for conservation and that these species include species that are rare and threatened in Cameroon, and even one species endemic to the country. This study highlights the botanical importance of communal forests in Cameroon and recommends that botanical assessments of these forests are performed to contribute to the sustainable management and conservation of their biodiversity.

SummaryWe revise and update the records of strict and near-endemic species of the Bali Ngemba Forest Reserve, the largest known surviving patch (c. 8 km2in area) of submontane or cloud forest in the Bamenda Highlands, Cameroon which have lost >96 % of their original forest due to human activities. Nine strict endemics, and 11 near endemics are now documented, a drop from the number recorded after the first survey in 2004, since when five of the provisionally named species have been formally published.We test the hypothesis that a further one of the provisionally named putative Bali Ngemba new species,Veprissp. A, an 8 – 20 m tall tree from cloud forest in the 1310 – 1600 m altitudinal band, is indeed new to science. We compare it morphologically with other multicarpellate, apocarpous, trifoliolate Cameroon tree species formerly placed in the genusOriciaPierre until they were subsumed intoVeprisby Mziray (1992). These areVepris trifoliolata(Engl.) Mziray andV. gabonensis(Pierre) Mziray. We conclude thatVeprissp. A is a new undescribed species here named asVepris onanae. The new species is illustrated, mapped and its conservation status assessed as Endangered using the 2012 IUCN standard due to the threats of habitat clearance from agricultural pressures at its three locations all of which remain formally unprotected.Vepris onanaeappears unique among the Guineo-Congolian African oricioid species ofVeprisin occurring in cloud forest, the other species, apart fromV. renieriiof the Albertine Rift, occurring in lowland forest. It also differs in the very broad, (7.8 –) 11.3 – 18 cm wide leaflets of the flowering stems which have a 6-18(−30) mm long, narrowly triangular acumen (vs leaflets We report for the first time on stage-dependent leaf heteromorphy inVeprisand characterise a level of sexual dimorphism more advanced than usual in the genus.We highlight the importance of protecting Bali Ngemba and other forest patches in the Bamenda Highlands if species such asVepris onanaeare not soon to become extinct.

SummaryWe revise and update the records of strict and near-endemic species of Mt Kupe, Cameroon respectively from 31 strict endemics in 2004, to 25 today, and with near-endemic species 30, unchanged in number but with turnover. The changes result from new collections, discoveries and taxonomic changes in the last 16 years. While 15 of the provisionally named putative endemic species have now been formally published, a further 18 have not. The majority of the 30 near-endemic species (18) are shared with the adjacent Bakossi Mts, far exceeding the numbers shared with the more distant Mt Etinde-Mt Cameroon, Rumpi Hills and Ebo forest areas (sharing three near-endemic species each with Mt Kupe). We test the hypothesis that a further one of the provisionally named putative Mt Kupe species,Veprissp. 1 from submontane forest near the summit, is indeed new to science. We compare it morphologically with the two other bicarpellate high altitude Cameroon Highland tree speciesVepris montisbambutensisOnana andVepris baliCheek, concluding that it is a new undescribed species here named asVepris zapfackii. The new species is illustrated, mapped and its conservation status assessed as Critically Endangered using the 2012 IUCN standard due to habitat clearance from agricultural pressures at its sole location which is unprotected.Vepris zapfackiiandV. baliappear unique in African trifoliolate species of the genus in having opposite leaves.Vepris zapfackiidiffers in having hairy petiolules and midribs and petiolules with the blade decurrent distally, narrowing towards a winged-canaliculate base (vs glabrous and petiolule long, terete), and sparsely golden hairy pistillodes and a glabrous calyx (vs densely black hairy pistillodes, and sepals hairy).

Large-scale identification of land use and land cover change in a tropical forest is a challenge to landscape designers and forest ecologists. Here, Landsat images acquired during the years 2000, 2009, and 2018 were used to assess the spatial-dynamics of land use and land cover (LULC) during the last two decades (2000–2018). A classification system composed of six classes—dense forest with (high tree density and low tree density), swampy Raphia forest, swampy flooded forest and savanna were designed as LULC for this study. A maximum likelihood classification was used to classify Landsat images into thematic areas. Elsewhere, Landsat-based LULC mapping, post classification at the per-pixel scales and self-knowledge on the land cover change processes were combined to analyze LULC change, forest loss and change trajectories in Doume Communal Forest in eastern Cameroon. The results show that half of the study area changed in 2000–2009 and that the different types of LULC changes increased and involved more diverse and characteristic trajectories in 2009–2018 compared to 2000–2009. Degradation to a dense forest with low tree density and swampy Raphia forest was dominant, and the forest was mostly lost due to trajectories that involved conversion to agroforestry systems (10%), and a lesser extent due to trajectories that involved deforestation to grasslands (7%). The trajectory analyses did thus contribute to a more comprehensive analysis of LULC change and the drivers of forest loss and, therefore, is essential to improve the sustainable management and support spatial planning of the forest.

We test the hypothesis that the tree species previously known as Deinbollia sp. 2. is a new species for science. We formally characterise and name this species as Deinbollia onanae (Sapindaceae-Litchi clade) and we discuss it in the context of the assemblage of montane tree species in the Cameroon Highlands of West-Central Africa. The new species is a shade-bearing, non-pioneer understorey forest tree species reaching 15 m high and a trunk diameter that can attain over 40 cm at 1.3 m above the ground. Seed dispersal has been recorded by chimpanzees (Pan troglodytes ellioti) and by putty-nose monkeys (Cercopithecus nictitans) and the species is used by chimpanzees for nesting. Cameroon has the highest species-diversity and species endemism known in this African-Western Indian Ocean genus of 42, mainly lowland species. Deinbollia onanae is an infrequent tree species known from six locations in surviving islands of montane (sometimes also upper submontane) forest along the line of the Cameroon Highlands, including one at Ngel Nyaki in Mambilla, Nigeria. Deinbollia onanae is here assessed as Endangered according to the IUCN 2012 standard, threatened by severe fragmentation of its mountain forest habitat due to extensive and ongoing clearance for agriculture. The majority of the 28 tree species of montane forest (above 2000 m alt.) in the Cameroon Highlands are also widespread in East African mountains (i.e. are Afromontane wide). Deinbollia onanae is one of only seven species known to be endemic (globally restricted to) these highlands. It is postulated that this new species is morphologically closest to Deinbollia oreophila, a frequent species at a lower (submontane) altitudinal band of the same range. Detailed ecological data on Deinbollia onanae from the Nigerian location, Ngel Nyaki, where it has been known under the name Deinbollia “pinnata”, is reviewed.

Deinbollia onanae (Sapindaceae-Litchi clade) is here formally named and characterised as a new species to science, previously known as Deinbollia sp. 2. Cameroon has the highest species-diversity and species endemism known in this African-Western Indian Ocean genus of 42 species. Deinbollia onanae is an infrequent tree species known from five locations in surviving islands of montane (or upper submontane) forest along the line of the Cameroon Highlands. It is here assessed as Endangered according to the IUCN 2012 standard, threatened mainly by clearance of forest for agriculture. The majority of tree species characteristic of montane forest (above 2000 m alt.) in the Cameroon Highlands are also widespread in East African mountains (i.e. are Afromontane). Deinbollia onanae is one of only a very small number of species that are endemic (globally restricted to) the mountain range. It is postulated that this new species is in a sister relationship with Deinbollia oreophila, which is a frequent species of a lower (submontane) altitudinal band of the same range. It is further postulated that seed dispersal is or was by frugivorous birds, potentially turacos, alternatively by primates such as Preuss s monkey.

Dans le cadre de la Strategie et le Plan d’Action National sur la Biodiversite, afin d’ameliorer la comprehension et la documentation des ecosystemes, l’objectif de cette etude est l’identification et la cartographie les habitats naturels du Cameroun. Les materiels utilises ont ete les referentiels constitues de la classification standard des habitats de l’Union Internationale pour la Conservation de la Nature (UICN) pour la nomenclature, et les cartes phytogeographique, du relief et de l’hydrographie pour les habitats terrestres et aquatiques pour les cartes thematiques respectivement. Les methodes ont ete d’adapter la classification de l’UICN a celle des phytochories pour la nomenclature ; et la fabrique des delimitations sur des fonds de cartes existantes pour la cartographie. Les resultats obtenus sont la reconnaissance de differents types d’habitats naturels du Cameroun : trois cartes qui presentent les delimitations des habitats naturels terrestres par ecosysteme, et aquatiques par bassin hydrographique ; et que la repartition des habitats terrestres est correlee avec la nature des sols. Ces donnees completent les connaissances sur les ecosystemes et sont un outil pour l’application de l’approche par ecosysteme. C’est une contribution a la cartographie des milieux naturels du Cameroun en rapport avec la gestion durable de la biodiversite. Mots cles . Cameroun, habitat naturel, ecosysteme, phytochorie, hydrographie, cartographie. English Title: Natural habitats of the ecosystems of Cameroon Within the framework of the National Biodiversity Strategy and Action Plan, to improve the understanding and documentation of the ecosystems, the objectives of this study are the identification and the mapping of natural habitats of Cameroon. The materials used have been the referentials made up of the classification standard scheme of the habitats of the International Union for the Conservation of Nature (IUCN) for nomenclature, and the phytogeographic, relief and hydrography maps for terrestrial and aquatic habitats respectively. The methods have been to adapt the IUCN classification to that of phytochoria for nomenclature; and fabricate boundaries on existing maps for cartography. The results obtain are the recognition of different natural habitat types in Cameroon: three maps showing the boundaries of terrestrial natural habitats by ecosystem, and aquatic by watershed; and that the distribution of terrestrial habitats is correlated with the nature of the soil. These data improve the knowledge on ecosystems, and are an instrument for the implementation of the ecosystem approach. It’s a contribution to the mapping of natural environments of Cameroon in relation with the sustainable management of the biodiversity. Keywords : Cameroon, natural habitat, ecosystem, phytochoria, hydrography, mapping

Societal Impact Statement There is increasing awareness that plants and fungi, as natural solutions, can play an important role in tackling ongoing global environmental challenges. We illustrate how understanding current and projected threats to plants and fungi is necessary to manage and mitigate risks, while building awareness of gaps and bias in current assessment coverage is essential to adequately prioritize conservation efforts. We highlight the state of the art in conservation science and point to current methods of assessment and future studies needed to mitigate species extinction. Summary Plant and fungal biodiversity underpin life on earth and merit careful stewardship in an increasingly uncertain environment. However, gaps and biases in documented extinction risks to plant and fungal species impede effective management. Formal extinction risk assessments help avoid extinctions, through engagement, financial, or legal mechanisms, but most plant and fungal species lack assessments. Available global assessments cover c. 30% of plant species (ThreatSearch). Red List coverage overrepresents woody perennials and useful plants, but underrepresents single‐country endemics. Fungal assessments overrepresent well‐known species and are too few to infer global status or trends. Proportions of assessed vascular plant species considered threatened vary between global assessment datasets: 37% (ThreatSearch), and 44% (International Union for Conservation of Nature Red List of Threatened Species). Our predictions, correcting for several quantifiable biases, suggest that 39% of all vascular plant species are threatened with extinction. However, other biases remain unquantified, and may affect our estimate. Preliminary trend data show plants moving toward extinction. Quantitative estimates based on plant extinction risk assessments may understate likely biodiversity loss: they do not fully capture the impacts of climate change, slow‐acting threats, or clustering of extinction risk, which could amplify loss of evolutionary potential. The importance of extinction risk estimation to support existing and emerging conservation initiatives is likely to grow as threats to biodiversity intensify. This necessitates urgent and strategic expansion of efforts toward comprehensive and ongoing assessment of plant and fungal extinction risk.

In Tropical Africa, the genus Santiria Blume (Burseraceae) was considered as having one species, Santiria trimera (Oliv.) H.J. Lam ex Aubrév. The recent studies combining morphometric and molecular analysis revealed four isolated genetic groups that can be distinguished with clear morphological features. Following this study, a taxonomic revision of Santiria is conducted in tropical Africa, including the islands of the Gulf of Guinea. Four species are recognized: in addition to Santiria trimera, taxa previously described as Santiria balsamifera Oliv. Santiria ebo (Pierre) H.J. Lam and Santiria obovata (Pierre) H.J. Lam are re-established. Morphological distinctive traits that differentiate the four species are abundance of the elemi, presence/absence of lenticels on the twigs, pubescence of the inflorescence, and immature fruit color. A taxonomic key is provided. Three neotypes and two lectotypes are designated (including synonyms). Each species is described, affinities with other taxa, uses, field pictures and a preliminary conservation status according to the IUCN Categories and Criteria are provided., SCOPUS: ar.j, info:eu-repo/semantics/published

SummaryVepris verdoorniana(Rutaceae) has long been regarded as a widespread and variable species occurring from Guinea to Gabon. Recent evidence has shown that the original material from the type locality in Cameroon consists of two different species,V. verdoornianain the strict sense, endemic to Lower Guinea (Cameroon, Gabon and C.A.R. in W-C Africa) andV. letouzeyiOnana, which was thought to occur from Guinea to Cameroon. In this paper we show that the West African (Upper Guinea) material previously referred to asV. letouzeyi/V. verdoornianais separate morphologically from that in Cameroon (Lower Guinea). In fact the West African material referred to comprises two distinct species, here described asV. occidentalisCheek & Onana (Guinea to Ghana, but probably extending to Benin) a tree of lowland marginal dry evergreen and semi-deciduous forest, andV. ferCheek, a species restricted to four mainly lower submontane forest locations on iron substrates in Liberia and Sierra Leone (also Upper Guinea).Vepris occidentalisis here assessed as Least Concern due to its wide range and high frequency, whilstV. feris assessed as Endangered due to the low number of locations and threats from iron ore mining projects. Both new species are illustrated and mapped.

Dans le cadre des recherches sur la diversite biologique du Cameroun, il a ete constate que sur les cartes presentees comme representant les ecosystemes du Cameroun, tous les six ecosystemes ne sont pas representes, aussi la denomination des unites ecosystemiques n’est pas celle des ecosystemes. C’est pourquoi l’objectif de ce travail etait d’elaborer une carte des ecosystemes du Cameroun conforme a la nomenclature de la Convention sur la Diversite Biologique. Le materiel est constitue de cartes thematiques des caracteres biophysiques du milieu. La methode est d’utiliser des documents deja publies. L’analyse de la nomenclature des ecosystemes a permis d’identifier les six ecosystemes du Cameroun. Puis les couches des cartes thematiques ont ete superposees pour cartographier les ecosystemes. C’est la carte phytogeographique qui est le modele et la base de la delimitation des ecosystemes. Le resultat est la carte des six principaux ecosystemes: l’ecosysteme d’eau douce qui comprend les lacs naturels et artificiels, les milieux humides, les cours d’eau repartis dans tout le territoire ; l’ecosysteme semi-aride reparti sur la plaine du Diamare et une partie de la cuvette de la Benoue ; l’ecosysteme de savane tropicale boisee sur la cuvette de la Benoue, la plaine du nord, le plateau de l’Adamaoua, les hautes terres de l’Ouest et le nord du plateau meridional ; l’ecosysteme de montagne qui est un archipel reparti sur les montagnes au-dessus de 1200 m au nord et 1500 m au sud reparti sur la ligne volcanique du Cameroun ; l’ecosysteme de foret tropicale dense humide qui occupe la plaine littorale et le plateau meridional ; et enfin l’ecosysteme marin et cotier localise sur la cote et le plateau continental. La superficie approximative occupee par chaque ecosysteme a ete calculee. En conclusion cette carte repond a une lacune par la documentation de la diversite biologique du Cameroun dans le volet de la connaissance des ecosystemes. C’est un outil pour la planification, la gestion durable des ressources biologiques, l’exercice de la souverainete sur la biodiversite, l’enseignement et la recherche sur les ressources biologiques en tenant compte de tous les milieux naturels. Mots cles : Cameroun, caracteres, carte, ecosysteme, nomenclature, biodiversite.

Giresse et al. (1) criticize both our paleoclimatic reconstruction and our inferred anthropogenic origin of the late Holocene rainforest crisis (LHRC) (2). However, their argumentation, which is combined with alleged evidence for a climatic change during the LHRC, lacks strong support. Citing studies describing both brief (weeklong) and limited periods of leaf wax production in deciduous trees, Giresse et al. (1) conclude that leaf waxes cannot record the environmental variability of a full season. However, this argument is flawed, as evergreen and subtropical deciduous trees produce leaf waxes over much longer timescales—their δD (δDwax) values have been shown to capture environmental variability on even seasonal timescales (3, 4 … [↵][1]1To whom correspondence should be addressed. Email: yannickgarcin{at}yahoo.fr. [1]: #xref-corresp-1-1

Clist et al. (1) challenge our conclusions (2), criticizing our archaeological synthesis to maintain that the late Holocene rainforest crisis (LHRC) in Western Central Africa (WCA) was not triggered by human activity. Clist et al. (1) claim that the archaeological 14C dates we used were not critically evaluated, as we were more concerned with the quantity of dates rather than their quality. However, a careful reading of our article (2) and its associated SI Appendix unambiguously documents that we cautiously weighted the radiometric dates by applying a binning in space and time to correct for investigator bias and oversampling at different sites, following refs. 3⇓–5; this … [↵][1]1To whom correspondence should be addressed. Email: yannickgarcin{at}yahoo.fr. [1]: #xref-corresp-1-1

(IF 9.58; Q1); International audience; A potential human footprint on Western Central African rainforests before the Common Era has become the focus of an ongoing controversy. Between 3,000 y ago and 2,000 y ago, regional pollen sequences indicate a replacement of mature rainforests by a forest–savannah mosaic including pioneer trees. Although some studies suggested an anthropogenic influence on this forest fragmentation, current interpretations based on pollen data attribute the ‘‘rainforest crisis’’ to climate change toward a drier, more seasonal climate. A rigorous test of this hypothesis, however, requires climate proxies independent of vegetation changes. Here we resolve this controversy through a continuous 10,500-y record of both vegetation and hydrological changes from Lake Barombi in Southwest Cameroon based on changes in carbon and hydrogen isotope compositions of plant waxes. δ13C-inferred vegetation changes confirm a prominent and abrupt appearance of C4 plants in the Lake Barombi catchment, at 2,600 calendar years before AD 1950 (cal y BP), followed by an equally sudden return to rainforest vegetation at 2,020 cal y BP. δD values from the same plant wax compounds, however, show no simultaneous hydrological change. Based on the combination of these data with a comprehensive regional archaeological database we provide evidence that humans triggered the rainforest fragmentation 2,600 y ago. Our findings suggest that technological developments, including agricultural practices and iron metallurgy, possibly related to the large-scale Bantu expansion, significantly impacted the ecosystems before the Common Era.

RESUME La taxonomie des Rutaceae-Toddalieae du Cameroun revisitee sur la base de l'analyse des caracteres morphologiques du materiel fertile a permis de reconnaitre quatre especes nouvelles dont Vepris adamaouae Onana, sp. nov. par le limbe des folioles decurrent sur le petiolule, des inflorescences longues a axes filiformes et des etamines environ deux fois plus longues que les petales ; V. araliopsioides Onana, sp. nov., par les feuilles 5-foliolees et des fruits a exocarpe foveole ; V. letouzeyi Onana, sp. nov. par des petioles ailes, des fruits a exocarpe sillonne et finement foveole ; et V. montisbambutensis Onana, sp. nov. par la plus petite taille des feuilles et des fruits par rapport aux autres especes du genre. Par ailleurs le materiel qui se distingue par les petiolules reduits a un renflement represente certainement une espece nouvelle qui n'a pas ete validee a cause de l'absence de fleurs et fruits matures. Toddaliopsis ebolowensis (Engl.) Onana, comb. nov. est lectotypifie, ce qui permet la ...

The observation that the hydrogen isotope composition (delta D) of leaf wax lipids is determined mainly by precipitation delta D values, has resulted in the application of these biomarkers to reconstruct paleoclimate from geological records. However, because the delta D values of leaf wax lipids are additionally affected by vegetation type and ecosystem evapotranspiration, paleoclimatic reconstruction remains at best semi-quantitative. Here, we used published results for the carbon isotope composition (delta C-13) of n-alkanes in common plants along a latitudinal gradient in C-3/C-4 vegetation and relative humidity in Cameroon and demonstrated that pentacyclic triterpene methyl ethers (PTMEs) and n-C-29 and n-C-31 in the same soil, derived mainly from C-4 graminoids (e.g. grass) and C-3 plants (e.g. trees and shrubs), respectively. We found that the delta D values of soil n-C-27, n-C29 and n-C-31, and PTMEs correlated significantly with surface water delta D values, supporting previous observations that leaf wax lipid delta D values are an effective proxy for reconstructing precipitation delta D values even if plant types changed significantly. The apparent fractionation (epsilon(app)) between leaf wax lipid and precipitation delta D values remained relatively constant for C-3-derived long chain n-alkanes, whereas eapp of C-4-derived PTMEs decreased by 20 parts per thousand along the latitudinal gradient encompassing a relative humidity range from 80% to 45%. Our results indicate that PTME delta D values derived from C-4 graminoids may be a more reliable paleo-ecohydrological proxy for ecosystem evapotranspiration within tropical and sub-tropical Africa than n-alkane delta D values, the latter being a better proxy for surface water delta D values. We suggest that vegetation changes associated with different plant water sources and/or difference in timing of leaf wax synthesis between C-3 trees of the transitional class and C-3 shrubs of the savanna resulted in a D depletion in soil long chain n-alkanes, thereby counteracting the effect of evapotranspiration D enrichment along the gradient. In contrast, evaporative D enrichment of leaf and soil water was significant enough to be recorded in the delta D values of PTMEs derived from C-4 graminoids, likely because PTMEs recorded the hydrogen isotopic composition of the same vegetation type.

With the emergence of a new field, biodiversity informatics, an important task has been to evaluate completeness of biodiversity information that is existing and available for various countries and regions. This paper offers a first and very basic assessment of sampling gaps and inventory completeness across the Cameroon Mountains. Because digital accessible knowledge is severely limited for the region, we relied on qualitative evaluations of inventory completeness, supplemented by large amounts of data from the National Herbarium of Cameroon (YA) database. Detailed botanical inventories have been developed for Mt Cameroon, the Kupe-Mwanenguba Mountains, Mt Oku, and the Mambila Plateau, leaving substantial geographic and environmental coverage gaps corresponding to Rumpi Hills, Mt Nlonako, Kimbi Fungom National Park, Bali and Bafut Ngemba, Mt Bamboutos, Kagwene, and Tchabal Mbabo. This paper provides a roadmap for a comprehensive botanical survey for this region. Completing this survey plan, the resulting data will allow researchers to track changes in biodiversity and identify priority areas for conservation on the various mountain ranges that make up this important biodiversity hotspot.

Vepris mbamensis Onana, sp. nov., qui presente des petiolules renfles, est reconnue distincte des autres especes connues de Vepris Comm. ex A.Juss. en Afrique apres etude du materiel africain du genre. La nouvelle espece est decrite et typifiee. La cle des especes camerounaises du genre Vepris est mise a jour afin d'y integrer la nouvelle espece. Le specimen sur lequel est base le nom invalide Diphasia mildbraedii Engl. de la Republique Centrafricaine (R.C.A.) montre des caracteres morphologiques identiques a ceux de V. adamaouae Onana, notamment l'inhabituelle ramiflorie dans le genre. Par consequent le premier nom est place en synonymie du second et l'aire de repartition est etendue en R.C.A. L'identification des materiels recoltes au Nigeria etend aussi la repartition de V. adamaouae a l'ouest. Une cle permettant de distinguer les especes camerounaises a fruits sillonnes est presentee. Vepris mbamensis Onana, sp. nov. et V. adamaouae sont illustrees, et une carte de distribution des deux especes est presentee.

Vepris bali is the first known species of Vepris in WC Africa with opposite, trifoliolate leaves and is further unusual for its long petiolules. Known only from Bali Ngemba Forest Reserve, a remnant of submontane forest under great pressure of degradation in the Bamenda Highlands of Cameroon, it may already be extinct due to tree cutting and agricultural incursions. Here, V. bali is compared with other endemic cloud forest Vepris of the Cameroon Highlands and is described, illustrated, mapped and assessed as Critically Endangered (Possibly Extinct) using IUCN 2012 criteria.Citation: Cheek M., Gosline G. & Onana J.-M. 2018: Vepris bali (Rutaceae), a new critically endangered (possibly extinct) cloud forest tree species from Bali Ngemba, Cameroon. - Willdenowia 48: 285–292. doi: https://doi.org/10.3372/wi.48.48207Version of record first published online on 24 August 2018 ahead of inclusion in August 2018 issue.

A synoptic revision is presented for the genus Dacryodes Vahl in Africa. The studies are based on examination of herbarium material. Eighteen species are recognised, including two not well known due to poor material. The new species Dacryodes villiersiana Onana is described and illustrated. The conservation status of the species is discussed following the categories and criteria of IUCN (2001).

Biodiverse Cameroon has been highlighted as the top country in tropical Africa for plant species diversity per degree square, with a higher diversity than all other West African countries added together, and including two of the top documented centres of plant diversity in Tropical Africa. Despite its reduced taxonomic capacity, with only six active taxonomists a high level of botanical activity in the country has resulted in accomplishments such as the databasing of the YA Herbarium (over 60,000 records), which has an in-country collection coverage of almost 95% of the known plant species that are recorded for Cameroon. Other accomplishments are the Red Data Book of the Flowering Plants of Cameroon, several local checklists and published volumes of the Flore du Cameroun which covers 37% of the country's species. Currently the checklist of Cameroon records 7,850 taxa at species and infraspecific level. Resources are needed to support and heighten the profile of this small botanical community. Already thanks to strong collaboration between Cameroon and renowned botanical institutes of others countries, in particular France and United Kingdom, one hundred and thirteen plant families have been published and would help this country to complete the recording of its biodiversity towards contributing to the World Flora Online 2020 project. Resumo A República dos Camarões tem sido destacado como o principal país na África tropical para a diversidade de espécies de plantas por grau quadrado, com uma diversidade maior do que todos os outros países do Oeste Africano juntos, e incluindo dois dos maiores centros de diversidade de plantas documentadas na África Tropical. Apesar da sua reduzida capacidade taxonômica, com apenas seis taxonomistas ativos, um elevado nível de atividade botânica no país resultou na digitalizaçãodo herbário YA (com mais de 60.000 registros), tendo em seu acervo quase que 95% das espécies de plantas conhecidas para os Camarões. Outras conquistas para a botânica do país são o Livro Vermelho das Angiospermas dos Camarões, várias listas de verificação locais e volumes publicados da "Flore du Cameroun", que abrange 37% das espécies do país. Atualmente, a lista dos Camarões apresenta 7,850 táxons registrados tanto em nível específico como infraspecífico. Porém mais recursos financeiros são necessários para apoiar e elevar o perfil desta pequena comunidade botânica no país. Graças a uma forte colaboração entre os Camarões e renomados institutos de botânica de outros países, em especial da França e do Reino Unido, os tratamentos para cento e treze famílias de plantas já foram publicados e representam um importante passo para que este país possa completar o registro da sua biodiversidade, contribuindo assim para o projeto da Flora Mundial on-line 2020.

In freshwater settings, dinosterol (4 alpha,23,24-trimethyl-5 alpha-cholest-22E-en-3 beta-ol) is produced primarily by dinoflagellates, which encompass various species including autotrophs, mixotrophs and heterotrophs. Due to its source specificity and occurrence in lake and marine sediments, its presence and hydrogen isotopic composition (delta D) should be valuable proxies for paleohydrological reconstruction. However, because the purity required for hydrogen isotope measurements is difficult to achieve using standard wet chemical purification methods, their potential as a paleohydrological proxy is rarely exploited. In this study, we tested delta D values of dinosterol in both particulate organic matter (POM) and sediments of stratified tropical freshwater lakes (from Cameroon) as a paleohydrological proxy, the lakes being characterized by variable degrees of eutrophication. In POM and sediment samples, the delta D values of dinosterol correlated with lake water delta D values, confirming a first order influence of source water delta D values. However, we observed that sedimentary dinosterol was D enriched from ca. 19 to 54% compared with POM dinosterol. The enrichment correlated with lake water column conditions, mainly the redox potential at the oxic-anoxic interface (E-h OAI). The observations suggest that paleohydrologic reconstruction from delta D values of dinosterol in the sediments of stratified tropical lakes ought to be sensitive to the depositional environment, in addition to lake water delta D values, with more positive dinosterol delta values potentially reflecting increasing lake eutrophication. Furthermore, in lake sediments, the concentration of partially reduced vs. non-reduced C-34 botryococcenes, stanols vs. stenols, and bacterial (diploptene, diplopterol and beta beta-bishomohopanol) vs. planktonic/terrestrial lipids (cholesterol, campesterol and dinosterol) correlated with Eh OAI. We suggest using such molecular proxies for lake redox conditions in combination with dinosterol delta D values to evaluate the effect of lake trophic status on sedimentary dinosterol delta D values, as a basis for accurately reconstructing tropical lake water delta D values. (C) 2015 Elsevier Ltd. All rights reserved.

Objectives: This paper seeks to assess information on the identity, traditional uses, safety and efficacy of Garcinia lucida Vesque (Essok in Boulou and Ewondo local language), in order to highlight it potential as species to be registered in medicinal plant list and formularies needed for the development of monographs leading to local production of phytomedicines. Methodology and Results: Ethnobotanical survey was carried in the Bipindi-Akom II region (South Cameroon) with the help of interviews based on standardised questionnaires addressed to key-informants. Bark and seeds were the major parts used, highly appreciated due to its properties in preventing consumers from poison, diarrhoea and headaches. The most important therapeutic indications were additive to palm wine, antidote to poisoning, gastritis and snake bite. Other uses in treating included gynaecological pains and infections, sexual diseases and cancers. The bark was also believed by local people to act on the stability of chemical antibiotic drugs in pharmacy, while leaves were used as insect repellent against mosquitoes and cockroaches. Conclusions and application of findings: As an additive in palm wine processing, poisoning antidote, aphrodisiac and medicines, bark and seeds are widely used in the Bipindi-Lolodorf-Akom II area, in the Centre and South regions of Cameroon, in Gabon and Equatorial Guinea, in Central Africa and West Africa. This similarity of use across many regions is considered as important biological activity marker tools guiding plant parts or species selection in drug discovery and development using ethnopharmacological approach. Through the ethnobotanical and biological tests, assessed, accurate information is provided to substantiate safety and efficacy of G. lucida and to satisfy the requirements of official compendia such as pharmacopoeia. Further studies are needed to understand the effects of bark and seeds as additive to palm wine, as well as the interaction between bark and chemical antibiotic drugs. Keywords: Garcinia lucida , traditional uses, medicinal plant list, monograph, pharmacopoeia, phytomedicine production

A new combination, Cuviera cuvieroides (Wernham) Onana is proposed for the Central African taxon currently known as Globulostylis cuvieroides Wernham. A key to distinguish the seven species of the subgenus Globulostylis Verdc. is presented.

Dacryodes edulis is a fruit tree growing naturally in the rainforests of Central Africa. To provide data to scientists and forest managers for the habitat of D. edulis in the wild, the study of ecological niche and environmental adaptation was carried out. The geographical coordinates of 168 collections of wild individuals and 19 climatic parameters were treatedunder Geographical Information System. Potential spatial richness, favourable climatic parameters and elevation of the species were described. The favourable climatic conditionsfor natural growth of D. edulis were mainly revealed in the forests of Gabon and Equatorial Guinea. In Cameroon, these conditions were well marked in the regions of Kribi and Bipindi(South), in the forest of Yingui and Yabassi (Littoral), in the Dja Forest (East) and South-West towards the border with Nigeria. The mean of favourable annual precipitation is 2205.26 ± 505.5 mm per year. The optimal annual mean temperatures stretch from 23.5 to 25.5°C. The favourable elevations stretch from 0 to 800 m. These values are smaller than ones for domesticated individuals which represent fundamental climatic niche. Prospect inforest areas with the best favourable climatic conditions and elevation for natural growth ofD. edulis should be encouraged to ensure in situ conservation of wild populations for maintaining genetic diversity. Key words: Dacryodes edulis, ecological niche, environmental adaptation, in situconservation.

Hydrogen isotope values (delta D) of sedimentary aquatic and terrestrial lipid biomarkers, originating from algae, bacteria, and leaf wax, have been used to record isotopic properties of ancient source water (i.e., precipitation and/or lake water) in several mid-and high-latitude lacustrine environments. In the tropics, however, where both processes associated with isotope fractionation in the hydrologic system and vegetation strongly differ from those at higher latitudes, calibration studies for this proxy are not yet available. To close this gap of knowledge, we sampled surface sediments from 11 lakes in Cameroon to identify those hydro-climatological processes and physiological factors that determine the hydrogen isotopic composition of aquatic and terrestrial lipid biomarkers. Here we present a robust framework for the application of compound-specific hydrogen isotopes in tropical Africa. Our results show that the delta D values of the aquatic lipid biomarker n-C(17) alkane were not correlated with the delta D values of lake water. Carbon isotope measurements indicate that the n-C(17) alkane was derived from multiple source organisms that used different hydrogen pools for biosynthesis. We demonstrate that the delta D values of the n-C(29) alkane were correlated with the delta D values of surface water (i.e., river water and groundwater), which, on large spatial scales, reflect the isotopic composition of mean annual precipitation. Such a relationship has been observed at higher latitudes, supporting the robustness of the leaf-wax lipid delta D proxy on a hemispheric spatial scale. In contrast, the delta D values of the n-C(31) alkane did not show such a relationship but instead were correlated with the evaporative lake water delta D values. This result suggests distinct water sources for both leaf-wax lipids, most likely originating from two different groups of plants. These new findings have important implications for the interpretation of long-chain n-alkane delta D records from ancient lake sediments. In particular, a robust interpretation of palaeohydrological data requires knowledge of the vegetation in the catchment area as different plants may utilise different water sources. Our results also suggest that the combination of carbon and hydrogen isotopes does help to differentiate between the metabolic pathway and/or growth form of organisms and therefore, the source of hydrogen used during lipid biosynthesis.

International audience; Background and aims Species delimitation remains a difficult task in many groups of organisms. Even widespread and conspicuous tropical trees make no exception. Santiria trimera, an African rainforest tree, displays substantial morphological variability. While classical analysis of historical herbarium samples lead to the recognition of a single species, two morphotypes of S. trimera are regularly collected in Gabon and Equatorial Guinea, sometimes in sympatry: one form with stilt roots (SR) and another form without stilt roots (NSR). Methods To assess whether these forms constitute distinct taxa and to understand evolutionary processes within African Santiria, we combined a morphological and a spatial analysis of both sympatric morphotypes in northern Gabon with a phylogenetic analysis of samples from West and Central Africa, including the island of Sao Tome. Key results In Gabon, morphological traits, chloroplast DNA (cpDNA) and nuclear DNA (nuDNA) sequences congruently lead to the recognition of two well differentiated and reproductively isolated taxa corresponding to SR and NSR morphotypes. However, rare cases of the SR morphotype bearing DNA sequences typical of NSR individuals suggest that hybridization might sometimes occur. No evidence for habitat specialization of the two taxa was found. DNA sequences from Sao Tome formed monophyletic clades at both marker types and the nuDNA gene tree suggests that the Sao Tome population probably originated from Central Africa and subsequently underwent allopatric differentiation from continental populations. Conclusion In Central Africa, S. trimera is composed of at least two distinct sympatric species following the Biological Species Concept and calls for further morphological and phenological studies and experimental crosses between them to specify their taxonomic status. Our results also show that classical taxonomic species delimitation may not always be congruent with the Biological Species Concept, calling for more population-based in situ morphological and molecular genetic analyses.

Western Cameroon has one of the richest floras in Tropical Africa. This paper examines the subject of the phytogeographic delimitation of the area. The Cross River-Sanaga River interval is known to be of importance in primate geography. Is it also important for plants? The characteristics of the area may be more a product of the Cameroon Highlands than of the flora of lowland Guinea: more work is needed to decide this.

The genus Allexis is known only from West and Central Africa (Jenik & Enti 1968). So far, only three species have been described (Melchior 1924). Revision of the Central African Violaceae (Achoundong 1997), and production of an account for Flore du Cameroun has revealed a fourth species, described here as Allexis zygomorpha. Further exploration of the littoral forest in Cameroon may yield yet more species in this genus.

Despite the severe threats to plant habitats and high levels of extinction risk for plant species in many parts of the world, plant conservation priorities are often poorly represented in national and global frameworks because of a lack of data in an accessible and consistent format to inform conservation decision making. The Important Plant Areas (IPAs) criteria system offers a pragmatic yet scientifically rigorous means of delivering these datasets, enabling informed national- or regional-scale conservation prioritisation, and contributing significantly towards global prioritisation systems including the International Union for Conservation of Nature Key Biodiversity Areas (KBAs) Standard. In this paper, we review the IPA rationale and progress on IPA identification to date, including the perceived limitations of the process and how these may be overcome. We then present a revised set of criteria for use globally, developed through the combined experiences of IPA identification over the past decade and a half and through a recent global consultation process. An overview of how the revised IPA criteria can work alongside the newly published KBA Standard is also provided. IPA criteria are based around a sound, scientific, global framework which acknowledges the practical problems of gathering plant and habitat data in many regions of the world, and recognises the role of peer reviewed expert opinion in the selection process. National and sub-national engagement in IPA identification is essential, providing a primary route towards long term conservation of key sites for plant diversity. The IPA criteria can be applied to the conservation of all organism groups within the plant and fungal kingdoms.

Carapa species are trees and shrubs of tropical forests. In Africa, although Carapa species are widely distributed and diversified from Senegal to Rwanda, their commercial exploitation remains restricted despite their known domestic uses. In Senegal, Carapa is most abundant in Mid and lower Casamance and in the gallery forests of East Senegal. Carapa species are recognised for socio-cultural or medicinal importance throughout their area of distribution.Traditionally the oil is extracted by women in menopause and is used to treat dozens of illnesses and in cosmetics. Leaves, bark and roots are also used., Les Carapa sont des arbres et arbustes des forêts tropicales. En Afrique, si les Carapa sont largement distribués et diversifiés du Sénégal au Rwanda, leur exploitation commerciale demeure cependant embryonnaire malgré des usages domestiques reconnus. Au Sénégal les Carapa sont plus abondants en moyenne et basse Casamance et dans les galeries forestières des savanes du Sénégal oriental. Les Carapa sont d'importance socio-culturelle ou médicinale reconnue sur toute leur aire de distribution. L'huile est traditionnellement extraite par les femmes ménopausées et est utilisée dans le traitement d'une dizaine de maladies et en cosmétique. Les feuilles, les écorces et les racines sont également utilisées.

Proceedings of the 18th AETFAT Congress held in Yaounde, Cameroon; International audience; Carapa species are trees and shrubs of tropical forests. In Africa, although Carapa species are widely distributed and diversified from Senegal to Rwanda, their commercial exploitation remains restricted despite their known domestic uses. In Senegal, Carapa is most abundant in Mid and lower Casamance and in the gallery forests of East Senegal. Carapa species are recognised for socio-cultural or medicinal importance throughout their area of distribution.Traditionally the oil is extracted by women in menopause and is used to treat dozens of illnesses and in cosmetics. Leaves, bark and roots are also used.; Les Carapa sont des arbres et arbustes des forêts tropicales. En Afrique, si les Carapa sont largement distribués et diversifiés du Sénégal au Rwanda, leur exploitation commerciale demeure cependant embryonnaire malgré des usages domestiques reconnus. Au Sénégal les Carapa sont plus abondants en moyenne et basse Casamance et dans les galeries forestières des savanes du Sénégal oriental. Les Carapa sont d'importance socio-culturelle ou médicinale reconnue sur toute leur aire de distribution. L'huile est traditionnellement extraite par les femmes ménopausées et est utilisée dans le traitement d'une dizaine de maladies et en cosmétique. Les feuilles, les écorces et les racines sont également utilisées.