@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 {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 {71, title = {Three new or little-known Chassalia (Rubiaceae) species from west and central Africa}, journal = {Nordic Journal of Botany}, volume = { 28}, year = {2010}, pages = {20}, chapter = {13}, abstract = {

A new species from Liberia and Co\ˆte d\’Ivoire, Chassalia bicostata O. Lachenaud \& Jongkind, is described and
compared with its two close relatives, C. pteropetala (K. Schum.) Cheek and C. pleuroneura (K. Schum.)
O. Lachenaud, both from central Africa. The latter is here transferred to Chassalia from Psychotria. All three species
share deeply bifid stipules, which are an unusual feature in Chassalia. Full descriptions and illustrations are given for
the three taxa.

}, author = {Lachenaud, Olivier and Jongkind, Carel} } @article {70, title = {Psychotria elephantina sp. nov. (Rubiaceae) an endangered rainforest shrub from Cameroon}, journal = { Nordic Journal of Botany}, volume = {31}, year = {2013}, pages = {573}, chapter = {569}, abstract = {

Psychotria elephantina Lachenaud \& Cheek is described as a new species. It is placed in P. sect. Involucratae (Petit) Verdc.,
endemic to the South West Region of Cameroon and is assessed as \‘ Endangered \’ (EN) using the IUCN criteria. Th e species
is distinctive in P. sect. Involucratae due to its long petioles (6.5 \– 12.0 cm), involucres of two pairs of large free bracts and
green corollas with included stamens in both longistylous and brevistylous fl owers.

}, author = {Cheek, Martin and Lachenaud, Olivier} } @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 {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} }