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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.

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).

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 Dacryodes edulis (G.Don) H.J.Lam (known as ‘African plum’ or ‘safoutier/prunier’), a socio-economically important indigenous fruit tree species in West and Central Africa. We compared wild and cultivated individuals for their sex distribution; flower, fruit and seed morphometric characteristics; seed germination temporal dynamic and fruit lipid composition. We found a higher percentage of male and male-hermaphrodite sexual types in wild populations than in cultivated ones; a lower fruit and seed mass in wild individuals; and similar mean time of germination, oil content and fatty acid composition between wild and cultivated individuals. Our results are interpreted in light of the presence of a domestication syndrome in D. edulis.

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.

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.

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.

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 ...

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.

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.

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.