@article {104, title = {A synopsis of the Sabicea floribunda group (Rubiaceae) from Central Africa, including three new species.}, journal = {Candollea }, volume = {75}, year = {2020}, chapter = {115}, abstract = {

This paper presents a taxonomic revision of the Sabicea floribunda K. Schum. group. Eight species are recognised, of which three are newly described: Sabicea couteronii O. Lachenaud, Zemagho \& Sonk\é (Cameroon, Gabon and Republic of Congo), Sabicea dichrosepala O. Lachenaud, Zemagho \& Sonk\é and Sabicea rubiginosa O. Lachenaud, Zemagho \& Sonk\é (both endemic to Gabon). One subspecies is also described: Sabicea sanguinosa subsp. viridis O. Lachenaud, Zemagho \& Sonk\é and two varieties: Sabicea floribunda var. anisostegia O. Lachenaud, Zemagho \& Sonk\é and Sabicea floribunda var. paludosa O. Lachenaud, Zemagho \& Sonk\é. Lectotypes are selected for Sabicea floribunda var. paucinervis Wernham, Sabicea nobilis R.D. Good, Sabicea segregata Hiern and Sabicea henningsiana B\üttner. All species are illustrated with photographs, and the three new ones also with line drawings; distribution maps and IUCN conservation status assessments are also presented for all taxa.

}, keywords = {RUBIACEAE {\textendash} Sabicea {\textendash} Pseudosabicea {\textendash} Central Africa {\textendash} Lower Guinea {\textendash} Gabon {\textendash}Cameroon {\textendash} Republic of Congo {\textendash} Taxonomy {\textendash} New species.}, doi = {DOI: http://dx.doi.org/10.15553/c2020v751a12.}, author = {Lachenaud, Olivier and Zemagho, Lise and Sonk{\'e}, Bonaventure} } @article {80, title = {Two new Sabicea (Rubiaceae) species from West Central Africa: Sabicea bullata and Sabicea urniformis. Phytotaxa 173 (4): 285{\textendash}292.}, journal = {Phytotaxa}, volume = {4}, year = {2014}, month = {2 Jul. 2014}, chapter = {285}, abstract = {

Two distinctive new species of Sabicea (Rubiaceae) from the Lower Guinea region are described and illustrated. Sabicea bullata is easily recognized by its cordate leaves, which are strongly bullate above, and its sessile glomerulate inflorescences. It is restricted to the Rumpi Hills and Bakossi Mountains, in southwestern Cameroon. Sabicea urniformis, from southern Gabon and Congo-Brazzaville, is remarkable in having discolorous leaves and an urn-shaped involucre with bracts shortly connate at the base. Detailed descriptions and botanical drawings are provided, conservation status assessed and taxonomic affinities discussed.

}, keywords = {Conservation status, IUCN Red List Categories, Lower Guinea, Rumpi Hills}, author = {Zemagho, Lise and Lachenaud, Olivier and Liede-Schumann, Sigrid and Deissen, Steven and Sonk{\'e}, Bonaventure} } @article {79, title = {Synopsis of the genus Massularia (Rubiaceae) with a new species from Central Africa.}, journal = {Phytotaxa}, volume = {3}, year = {2015}, month = {25 Mar. 2015}, chapter = {263}, abstract = {

Based on a careful examination of more than 700 herbarium specimens and field investigation, a comprehensive revision of the genus Massularia is given. Massularia stevartiana, a new species from Central African Republic, Cameroon and Gabon is described and illustrated. The novelty is distinguished from M. acuminata, the only other species previously recognized in the genus, by its smaller leaves and flowers. For the two species recognized we provide a morphological description, distribution, habitat, phenology and IUCN conservation status assessment. Distribution maps and a dichotomous key are also provided

}, keywords = {Cameroun, Central African Republic, Gabon, Guineo-Congolian Region, IUCN Red List Categories and Criteria, shrub, taxonomy, tropical African flora}, author = {Sonk{\'e}, Bonaventure and Bidault, Ehoarn and Droissart, Vincent} } @article {78, title = {R{\'e}vision du genre africain Sherbournia G.Don (Rubiaceae, Gardenieae)}, journal = { Syst. Geogr. Pl. }, volume = {75}, year = {2005}, pages = {91}, chapter = {61}, abstract = {

Revision of the African genus Sherbournia (Rubiaceae, Gardenieae). A revision of Sherbournia G.Don is given, based mainly on a study of the herbarium specimens at BATA, BM, BR, BRLU, K, LBV, MO, P, SCA, WAG and YA. The general part gives a survey of the history of the genus; the morphological features (habit, leaves, stipules, domatia, flower, fruit characters) of the genus are reviewed and documented. The distribution maps of the species show the characteristic distribution pattern of a strict Guineo-Congolian genus. The taxonomic part gives keys and complete species treatments (synonymies, descriptions, distributional data, critical notes). The detailed examination of the specimens resulted in one novelty: Sherbournia batesii subsp. kivuensis Pauwels \& Sonk\é. Some taxonomic changes are made: Sherbournia streptocaulon (K.Schum.) Hepper var. situtunga N.Hall\é is proved to be synonymous with Sherbournia streptocaulon (K.Schum.) Hepper; Sherbournia bignoniiflora (Welw.) Hua var. brazzaei N.Hall\é, Amaralia palustris Wernh., Amaralia ekotokicola Wernh. are synonymous with Sherbournia bignoniiflora (Welw.) Hua. The subdivison of S. hapalophylla is reconsidered and two subspecies are proposed: S. hapalophylla subsp. hapalophylla and S. hapalophylla subsp. wernhamiana. According to those changes, S. hapalophylla (Wernham) Hepper var. henrihuana N.Hall\é and S. hapalophylla (Wernham) Hepper var. hapalophylla are put into synonymy with S. hapalophylla subsp. hapalophylla.

}, author = {Sonk{\'e}, Bonaventure and Pauwels, Luc} } @article {77, title = {A new species of Chassalia (Rubiaceae, Rubioideae) from southern Cameroon: C. bipindensis}, journal = { Kew Bull.}, volume = {61}, year = {2006}, pages = {589}, chapter = {585}, abstract = {

Chassalia bipindensis Sonk\é, Nguembou \& A. P. Davis (Rubiaceae), a new species from southern\ Cameroon, is described and illustrated. The conservation status and taxonomic affinities of the new species are
discussed.

}, keywords = {Cameroon, Chassalia, conservation, IUCN Red List Categories, rainforest, Rubiaceae, Rubioideae}, author = {Sonk{\'e}, Bonaventure and Nguembou, Charlemagne and Cheek, Martin and Davis, Aaron} } @article {75, title = {A new Argocoffeopsis (Coffeeae, Rubiaceae) from southern Cameroon: A. spathulata}, journal = {Blumea}, volume = {53}, year = {2008}, month = {532}, pages = {527}, abstract = {

A new species of Argocoffeopsis, A. spathulata, is described as new to science. A description, line
drawing, distribution map and conservation assessment are provided

}, keywords = {Argocoffeopsis, Cameroon, Coffeeae, IUCN., plant conservation}, author = {Davis, A. P. and Sonk{\'e}, Bonaventure} } @article {74, title = { Une esp{\`e}ce nouvelle de Bertiera (sous-genre Bertierella, Rubiaceae) d{\textquoteright}Afrique centrale atlantique}, journal = {31}, volume = {2}, year = {2009}, pages = {406}, chapter = {397}, abstract = {

A new species belonging to the genus Bertiera (subgenus Bertierella, Rubiaceae)
from West Central Africa (Cameroon, Equatorial Guinea and Gabon) is described.
Its diagnostic characters are elucidated, its taxonomic affi nities are
discussed and notes on its conservation status are provided.

}, keywords = {Bertiera, conservation, new species, Rubiaceae, West Central Africa}, author = {Nguembou, Charlemagne and Ewedje, D.K. E. and Droissart, Vincent and Stevart, Tariq and Sonk{\'e}, Bonaventure} } @article {72, title = {Colletoecema gabonensis, a third species of an unusual African genus of Rubiaceae}, journal = { Brittonia }, volume = {63}, year = {2011}, pages = {219}, chapter = {215}, abstract = {

As a result of ongoing studies of the Rubiaceae of Gabon, the new species
Colletoecema gabonensis is here described and illustrated. It is endemic to Gabon,
where it is the only species of the genus, and is so far only known from three collections
from the Ogoou\é-Lolo and Ngouni\é provinces. The new species is morphologically
intermediate between its two congeners, C. dewevrei (from Cameroon, Central
African Republic, Republic of the Congo, DR Congo, and Angola) and C. magna
(endemic to Cameroon). The new species agrees with C. dewevrei in having flowers
with exserted anthers and style, but differs in its sessile flowers and fruits. In the latter
characters, it resembles C. magna, from which it can be separated by its smaller fruits
and leaves, and by its different floral morphology. An IUCN conservation assessment
has been made and the species is provisionally assessed as Vulnerable, based on its
restricted area of occupancy and the small number of known locations

}, keywords = {Colletoecema, Gabon, IUCN conservation assessment, Rubiaceae, taxonomy}, author = {Dessein, Steven and Lachenaud, Olivier and Sonk{\'e}, Bonaventure} } @article {69, title = {Craterispermum parvifolium and C. robbrechtianum spp. nov. (Rubiaceae) from west central Africa}, journal = { Nordic Journal of Botany}, volume = {29}, year = {2011}, pages = {707}, chapter = {700}, abstract = {

Craterispermum parvifolium and C. robbrechtianum spp. nov. are described from the Lower Guinea Domain. Detailed
descriptions and distribution maps are provided for each species, their conservation status is assessed and their taxonomic
affinities are discussed. An identification key for the Craterispermum species of the Lower Guinea Domain is given.

}, author = {Taedoumg, Hermann and De Block, Petra and Hamon, Perla and Sonk{\'e}, Bonaventure} } @article {68, title = {Taxonomy and phylogenetics of Cuviera (Rubiaceae{\textendash}Vanguerieae) and reinstatement of Globulostylis with the description of three new species}, journal = {Botanical Journal of the Linnean Society}, volume = {173}, year = {2013}, month = {16 October 2013}, pages = {441}, chapter = {407}, abstract = {

Generic circumscriptions in tribe Vanguerieae (Rubiaceae) have been under discussion for a long time. Recent
molecular studies, while providing new insights, have not yet solved all the problems. In this study, the taxonomy
and phylogenetics of the genus Cuviera s.l. are investigated. On the basis of molecular and morphological evidence,
Cuviera is restricted to a group of ten West and Central African species. Globulostylis, previously included in
Cuviera, is reinstated as a distinct genus, with eight species from Central Africa. Both genera are revised; the
latter includes three new species (G. dewildeana, G. rammelooana and G. robbrechtiana) and two new combinations
(G. leniochlamys and G. uncinula). The close relationship of Cuviera s.s. and Globulostylis to Vangueriella is
shown. Six aberrant species (most from East Africa) are excluded from Cuviera, but further work is needed before
they can be confidently assigned to other genera.\ 

}, keywords = {Cameroon, Equatorial Guinea, Gabon, Tropical Africa}, author = {Verstraete, Brecht and Lachenaud, Olivier and Smeets, Erik and Dessein, Steven and Sonk{\'e}, Bonaventure} } @article {67, title = {Tree diversity of the Dja Faunal Reserve, southeastern Cameroon}, journal = {Biodiversity Data Journal}, volume = {2}, year = {2014}, chapter = {e1049}, abstract = {

The Dja Faunal Reserve located in southeastern Cameroon represents the largest and
best protected rainforest patch in Cameroon. Here we make available a dataset on the
inventory of tree species collected across the Dja. For this study nine 5 km long and 5 m
wide transects were installed. All species with a diameter at breast height greater than 10
cm were recorded, identified and measured. A total of 11546 individuals were recorded,
corresponding to a total of 312 species identified with 60 genera containing unidentified
taxa. Of the 54 identified families Fabaceae, Rubiaceae and Malvaceae were the most
species rich, whereas Fabaceae, Phyllantaceae and Olacaceae were the most abundant.
Finally, Tabernaemontana crassa was the most abundant species across the Reserve. This
dataset provides a unique insight into the tree diversity of the Dja Faunal Reserve and is
now publically available and usable.

}, keywords = {Africa, conservation, diversity, Dja Faunal Reserve, species inventory, transect}, author = {Sonk{\'e}, Bonaventure and Couvreur, Thomas} } @article {66, title = {Mixed-Forest Species Establishment in a Monodominant Forest in Central Africa: Implications for Tropical Forest Invasibility.}, journal = { PLoS ONE }, volume = {9}, year = {2014}, month = {20 May 2014}, chapter = {e97585}, abstract = {

Background: Traits of non-dominant mixed-forest tree species and their synergies for successful co-occurrence in
monodominant Gilbertiodendron dewevrei forest have not yet been investigated. Here we compared the tree species
diversity of the monodominant forest with its adjacent mixed forest and then determined which fitness proxies and life
history traits of the mixed-forest tree species were most associated with successful co-existence in the monodominant
forest.
Methodology/Principal Findings: We sampled all trees (diameter in breast height [dbh]$10 cm) within 661 ha
topographically homogenous areas of intact central African forest in SE Cameroon, three independent patches of G.
dewevrei-dominated forest and three adjacent areas (450\–800 m apart). Monodominant G. dewevrei forest had lower
sample-controlled species richness, species density and population density than its adjacent mixed forest in terms of stems
with dbh$10 cm. Analysis of a suite of population-level characteristics, such as relative abundance and geographical
distribution, and traits such as wood density, height, diameter at breast height, fruit/seed dispersal mechanism and light
requirement\–revealed after controlling for phylogeny, species that co-occur with G. dewevrei tend to have higher
abundance in adjacent mixed forest, higher wood density and a lower light requirement.
Conclusions/Significance: Our results suggest that certain traits (wood density and light requirement) and population-level
characteristics (relative abundance) may increase the invasibility of a tree species into a tropical closed-canopy system. Such
knowledge may assist in the pre-emptive identification of invasive tree species.

}, author = {Peh, KS-H and Sonk{\'e}, Bonaventure and S{\'e}n{\'e}, Olivier and Djuikouo, Marie-No{\"e}l and Nguembou, Charlemagne and Taedoumg, Hermann and Kouob, Serge and Lewis, Simon L.} } @article {65, title = {Characterizing the Phylogenetic Tree Community Structure of a Protected Tropical Rain Forest Area in Cameroon.}, journal = { PLoS ONE }, volume = {9}, year = {2014}, month = {17 June 2014}, chapter = {e98920}, abstract = {

Tropical rain forests, the richest terrestrial ecosystems in biodiversity on Earth are highly threatened by global changes. This
paper aims to infer the mechanisms governing species tree assemblages by characterizing the phylogenetic structure of a
tropical rain forest in a protected area of the Congo Basin, the Dja Faunal Reserve (Cameroon). We re-analyzed a dataset of
11538 individuals belonging to 372 taxa found along nine transects spanning five habitat types. We generated a dated
phylogenetic tree including all sampled taxa to partition the phylogenetic diversity of the nine transects into alpha and beta
components at the level of the transects and of the habitat types. The variation in phylogenetic composition among
transects did not deviate from a random pattern at the scale of the Dja Faunal Reserve, probably due to a common history
and weak environmental variation across the park. This lack of phylogenetic structure combined with an isolation-bydistance
pattern of taxonomic diversity suggests that neutral dispersal limitation is a major driver of community assembly in
the Dja. To assess any lack of sensitivity to the variation in habitat types, we restricted the analyses of transects to the terra
firme primary forest and found results consistent with those of the whole dataset at the level of the transects. Additionally
to previous analyses, we detected a weak but significant phylogenetic turnover among habitat types, suggesting that
species sort in varying environments, even though it is not predominating on the overall phylogenetic structure. Finer
analyses of clades indicated a signal of clustering for species from the Annonaceae family, while species from the
Apocynaceae family indicated overdispersion. These results can contribute to the conservation of the park by improving our
understanding of the processes dictating community assembly in these hyperdiverse but threatened regions of the world.

}, author = {Manel, St{\'e}phanie and Couvreur, Thomas and Munoz, Fran{\c c}ois and Couteron, Pierre and Hardy, Olivier and Sonk{\'e}, Bonaventure} } @article {44, title = {A new species of Tricalysia A. Rich. ex DC. (Rubiaceae) from western Cameroon}, journal = {Kew Bulletin}, volume = {57}, number = {3}, year = {2002}, note = {Times Cited: 0}, pages = {681-686}, abstract = {

Tricalysia lejolyana is described as a new species from the Banyang Mbo Wildlife Sanctuary in western Cameroon and its conservation status assessed. Its diagnostic characteristics are elucidated in relation to other taxa of the genus, in particular, to the species of the \&$\#$39;T. atherura\&$\#$39; group of Tricalysia subg. Tricalysia, sect. Tricalysia, in which it falls.

}, isbn = {0075-5974 (ISSN print)}, author = {Sonk{\'e}, Bonaventure and Cheek, Martin and Nambou D, Mercy and Robbrecht, Elmar} } @article {45, title = {A new species of Aulacocalyx (Rubiaceae, Gardenieae) from southern Cameroon}, journal = {Kew Bulletin}, volume = {60}, number = {2}, year = {2005}, note = {Times Cited: 0}, pages = {301-304}, abstract = {

Aulacocalyx camerooniana is described as a new species from Engon, (S Efoulan) in southern Cameroon. Its diagnostic characteristics are elucidated, notes on its conservation status are given and an updated key to species of Aulacocalyx occurring in Cameroon is provided.

}, isbn = {0075-5974}, author = {Sonk{\'e}, Bonaventure and Dawson, Sally and Beina, Denis} } @article {56, title = {Une nouvelle esp{\`e}ce de Coffea L. (Rubiaceae, Coffeeae) du Cameroun et quelques notes sur ses affinit{\'e}s avec les esp{\`e}ces voisines}, journal = {Adansonia}, volume = {26}, number = {2}, year = {2004}, note = {Times Cited: 0}, pages = {153-160}, abstract = {

A new species of Coffea (Rubiaceae) from Cameroon, Coffea fotsoana Stoffelen \& Sonke, is described, illustrated and mapped. Its relationships within the genus are discussed and a key is provided to all species occurring in,, Cameroon. The conservation status of this species is given, using IUCN Red List categories.

}, isbn = {1280-8571}, author = {Sonk{\'e}, Bonaventure and Stoffelen, Piet} } @article {57, title = {A reconsideration of the Lower Guinean species of Sericanthe (Rubiaceae, Coffeeae), with four new species from Cameroon and Gabon}, journal = {Botanical Journal of the Linnean Society}, volume = {169}, number = {3}, year = {2012}, note = {Times Cited: 0}, month = {Jul}, pages = {530-554}, abstract = {

The genus Sericanthe was established and its species were revised 30 years ago by one of the authors. Intensive recent botanical collecting in Lower Guinea (mainly southern Cameroon, Equatorial Guinea and Gabon) has made a reconsideration of species in this area necessary. Revision of the newly collected Lower Guinean herbarium specimens of Sericanthe (twice as many as were available at the time of the first revision) has brought four new species to light, namely S. gabonensis and S. mpassa from Gabon, S. lowryana from Cameroon and S. rabia from Cameroon and Gabon. Distributional data are much augmented, and distributional maps of all species from the area are provided. Four species were reported to be newly recorded for at least one country. The occurrence of the novelties in the main diversity centre of the genus is discussed in the context of the chorology of the entire genus Sericanthe. A first estimation of the conservation status for the new species is given. A synopsis of the genus Sericanthe in Lower Guinea with a taxonomic key is provided. (c) 2012 The Linnean Society of London, Botanical Journal of the Linnean Society, 2012, 169, 530554.

}, isbn = {0024-4074}, author = {Sonk{\'e}, Bonaventure and Taedoumg, Hermann and Robbrecht, Elmar} } @article {21, title = {New records for the flora of Cameroon, including a new species of Psychotria (Rubiaceae) and range extensions for some rare species}, journal = {Plant Ecology and Evolution}, volume = {146}, number = {1}, year = {2013}, note = {Times Cited: 0}, month = {2013}, pages = {121-133}, isbn = {2032-3913}, author = {Lachenaud, Olivier and Droissart, Vincent and Dessein, Steven and Stevart, Tariq and Simo, Murielle and Lemaire, Benny and Taedoumg, Hermann and Sonk{\'e}, Bonaventure} } @article {28, title = {A new heterophyllous Bertiera (Rubiaceae) from Cameroon and Gabon}, journal = {Systematics and Geography of Plants}, volume = {76}, number = {2}, year = {2006}, note = {Times Cited: 0}, pages = {211-216}, abstract = {

A new species of Bertiera (Rubiaceae) from Cameroon and Gabon, Bertiera heterophylla Nguembou \& Sonke, is described and illustrated. This new species belongs to the subgenus Bertiera and appears to be closely related to Bertiera bicarpellata. Bertiera heterophylla differs from B. bicarpellata in having lateral branches with terminal inflorescences while on the main stem, the inflorescences are axillary.

}, isbn = {1374-7886}, author = {Nguembou, Charlemagne and Esono, Pablo and Onana, Jean Michel and Sonk{\'e}, Bonaventure} } @article {8, title = {Two further new species of Psychotria (Rubiaceae) from western Cameroon}, journal = {Kew Bulletin}, volume = {60}, number = {2}, year = {2005}, note = {Times Cited: 0}, pages = {293-300}, chapter = {293}, abstract = {

Two new species of Psychotria (Rubiaceae) from western Cameroon are described and illustrated, their conservation status assessed and their taxonomic affinities discussed. Both species were discovered in Kupe and the Bakossi Mts. Psychotria geophylax Check \& Sonke has affinities with sect. Flaviflorae E. M. A. Petit, whereas P bakossiensis Cheek \& Sonke falls near sect. Involucratae E. M. A. Petit \& Verdc.

}, isbn = {0075-5974}, author = {Cheek, Martin and Sonk{\'e}, Bonaventure} }