KEW BULLETIN (2018) 73:12
DOI 10.1007/S12225-018-9739-4
ISSN: 0075-5974 (print)
ISSN: 1874-933X (electronic)
A revised key to the Warneckea species of Cameroon, and description
of Warneckea ngutiensis (Melastomataceae-Olisbeoideae), a new
Critically Endangered rainforest shrub
Robert Douglas Stone1 & Martin Cheek2
Summary. Warneckea ngutiensis R. D. Stone sp. nov. (Melastomataceae-Olisbeoideae) is described from near Nguti
in SW Region, Cameroon. Unique in section Strychnoides in having only a vestigial staminal oil gland, this rainforest
shrub is Critically Endangered due to an oil palm plantation project.
Key Words. Banyang Mbo, conservation, Earthwatch, extinction, Herakles, oil palm plantation.
Introduction
The genus Warneckea Gilg is closely allied with and has
previously been united with the genus Memecylon L., but is
phylogenetically distinct and generally distinguished by its
conspicuously 3-nerved leaf-blades (Stone 2006; Stone &
Andreasen 2010). On-going studies have steadily increased the number of known species of Warneckea, with
the most recent additions to the genus for Cameroon
being the range-restricted and threatened species
W. austro-occidentalis R. D. Stone and W. mangrovensis
(Jacq.-Fél.) R. D. Stone (Stone et al. 2009). With these
additions there were 12 species of Warneckea recognised
by Onana (2011) as occurring in Cameroon.
The present investigation concerns an unusual
Warneckea (represented by the specimen Pollard 552)
that was collected in November 2000 during a two-week
botanical survey and training exercise in the forest on
the southern boundary of the then Banyang Mbo
Wildlife Sanctuary, located near the town of Nguti in
Cameroon’s South-West Region. At the time of this field
survey, Banyang Mbo was co-managed by the Wildlife
Conservation Society (WCS) and the Ministry of Environment and Forest (MINEF). The survey was conducted as part of the Earthwatch-Darwin Initiative supported
“Plant Diversity of western Cameroon” project led by
botanists from Royal Botanic Gardens, Kew and the
National Herbarium of Cameroon. The methodology
used is detailed in Cheek & Cable (1997). Numerous
herbarium specimens were collected with the intention
that they would form the nucleus of data for a
'Conservation Checklist' of Banyang Mbo, in the series
that began with Mt Cameroon (Cable & Cheek 1998)
and continued with Kupe-Bakossi (Cheek et al. 2004),
Bali-Ngemba (Harvey et al. 2004), Mefou (Cheek et al.
2011) and Lebialem Highlands (Harvey et al. 2010).
Pollard 552 was later identified by one of us (RDS)
as a member of the main section present in W-C
Africa, Warneckea sect. Strychnoides (Engl.) Jacq.-Fél. ex
R. D. Stone (Stone & Andreasen 2010). However,
uniquely in this group, among other features, the
anther connectives of the Nguti taxon have only a
vestigial oil gland, a feature generally important at the
species-group or subgeneric level throughout the
subfamily Olisbeoideae. Accordingly, the species represented by Pollard 552 is here described as Warneckea
ngutiensis sp. nov.
The lowland evergreen forests of SW Cameroon
have proved to be rich in new species of plants, from
herbs, shrubs and lianas to canopy trees. Among those
published from the surveys discussed above, from the
forests adjoining those at Nguti, mainly from the
Bakossi area immediately adjacent to the South, are:
Coffea montekupensis Stoff. (Stoffelen et al. 1997),
Diospyros kupensis Gosline (Gosline & Cheek 1998),
Ancistrocladus grandifolius Cheek (2000), Ledermanniella
onanae Cheek (2003), Memecylon kupeanum R. D. Stone,
Ghogue & Cheek and M. bakossiense R. D. Stone,
Ghogue & Cheek (Stone et al. 2008). To date, two new
genera have also been discovered, Kupea Cheek & S.
A. Williams (Cheek et al. 2003) and Korupodendron Litt
& Cheek (2002). However, all of these taxa are
threatened with extinction due to habitat clearance,
mainly for agriculture (Onana & Cheek 2011). Efforts
are now being made to delimit the highest priority
areas in Cameroon for plant conservation as Tropical
Important Plant Areas (TIPAs) using the revised IPA
criteria set out in Darbyshire et al. (2017). This is
essential if more narrowly endemic species are not to
become extinct in Cameroon as has Oxygyne triandra
Schltr. (Cheek & Onana 2011).
Accepted for publication 14 February 2018.
1
School of Life Sciences, University of KwaZulu-Natal, Private Bag X01, Pietermaritzburg, 3209, South Africa. e-mail: StoneRD@ukzn.ac.za
2
Herbarium, Royal Botanic Gardens, Kew, Richmond, Surrey, TW9 3AE, UK.
© The Board of Trustees of the Royal Botanic Gardens, Kew, 2018
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KEW BULLETIN (2018) 73:12
Revised key to the species of Warneckea in Cameroon
1. Leaf bases rounded and narrowly cordate above the petiole; leaf-blades with principal nerves prominent on both
surfaces; inflorescences sessile or short-pedunculate; bracts persistent, imbricate-decussate; flowers sessile or
short-pedicellate (Warneckea sect. Guineenses R. D. Stone) . . . . . . . . . . . . . W. mangrovensis (Jacq.-Fél.) R. D. Stone
Leaf bases either rounded, cordate or cuneate (not rounded and narrowly cordate); leaf-blades with principal
nerves impressed on the upper surface, prominent on the lower; inflorescences conspicuously pedunculate,
in some cases with well-developed secondary axes (rarely contracted and subsessile); bracts ± rapidly
deciduous; flowers distinctly pedicellate (rarely subsessile); (Warneckea sect. Strychnoides (Engl.) Jacq.-Fél. ex R.
D. Stone) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 2
2. Inflorescences mainly below the leaves, fascicled at the swollen nodes of older branchlets (in W. memecyloides
borne in the lower leaf axils and at recently defoliated nodes); flowers distinctly pedicellate . . . . . . . . . . 3
Inflorescences mainly in the leaf-axils (in W. cinnamomoides and W. fosteri also at the recently defoliated nodes);
flowers in some species short-pedicellate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
3. Leaf-blades elliptic, 10 − 20 cm long × 4 − 9 cm wide, cuneate at base; inflorescences subsessile or on peduncles
2 − 7 mm long; fruits ± globose . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
Leaf-blades broadly elliptic to ovate, obovate, oblanceolate or suborbicular, mostly 12 − 32 cm long × 7 − 12 cm
wide, rounded to cordate or broadly cuneate at base; inflorescences on peduncles 6 − 30 (− 40) mm long;
fruits ellipsoid . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
4. Leaf-blades c. 10 cm long × 4 cm wide; inflorescences densely fascicled, on peduncles 2 − 7 mm
long . . . . . . . . . . . . . . . . . . . . . . . W. sapinii sensu Jacques-Félix (1983), but not as to type
Leaf-blades up to 20 cm long × 9 cm wide; inflorescences subsessile . . . . . . . . . . . . . . . . . . . . . . . . W. wildeana Jacq.-Fél.
5. Leaf-blades ovate to broadly elliptic or suborbicular, 12 − 18 cm long × 7 − 10 cm wide, rounded to shallowly cordate
at base; inflorescences borne in the lower leaf axils and at recently defoliated nodes; peduncles 6 – 10 mm long;
fruits 10 mm long × 6 mm wide . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . W. memecyloides (Benth.) Jacq.-Fél.
Leaf-blades larger, or if of similar dimensions then broadly cuneate to rounded at base (not cordate);
inflorescences fascicled at the swollen nodes of older branchlets; peduncles mostly c. 20 – 30 mm long; fruits
as above or larger . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
6. Leaf-blades ± oblanceolate, 20 – 32 cm long × 9 – 12 cm wide, narrowly cordate-auriculate at base; petioles 2 – 4 mm
long; petals blue-violet; fruits 10 mm long × 8 mm wide . . . . . . . . . . . . . . . . . . . . W. pulcherrima (Gilg) Jacq.-Fél.
Leaf-blades broadly ovate to broadly elliptic or broadly obovate, 12 – 19 cm long × 7.5 – 10 cm wide, broadly
cuneate to rounded at base; petioles 7 – 10 mm long; petals white; fruits 15 – 16 mm long × 10 – 11 mm
wide . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . W. austro-occidentalis R. D. Stone
7. Leaves apparently 1-nerved (the lateral pair of nerves submarginal, scarcely visible on the upper surface,
forming a series of shallow arches from the base between the junctions with the transverse veins);
inflorescences sessile to subsessile . . . . . . . . . . . . . . . . . . . . . . . . . . . W. bebaiensis (Gilg ex Engl.) Jacq.-Fél.
Leaves distinctly 3-nerved (the lateral pair of nerves clearly visible and percurrent from the base to the apex);
inflorescences as above or on peduncles to 10 mm . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8
8. Inflorescences on peduncles 2 – 10 mm long, directly umbelliform or if branched then each secondary axis ±
unbranched and 1 to 3-flowered; flowering pedicels slender, 4 – 10 mm long . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
Inflorescences compact, borne on peduncles up to 6 mm long or subsessile and reduced to 1 to 3 flowers;
flowers ± sessile or on pedicels 1 – 4 mm long . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
9. Leaves subcoriaceous; inflorescences axillary and sometimes terminal; fruits globose . . W. jasminoides (Gilg) Jacq.-Fél.
Leaves coriaceous; inflorescences in the lower leaf-axils and at the recently defoliated nodes; fruits globose or
ellipsoid . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10
10. Leaf-blades 8 − 14 cm long × 4 − 7 cm wide; fruits ellipsoid, 10 mm long × 6 mm
wide . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . W. cinnamomoides (G. Don) Jacq.-Fél.
Leaf-blades 6 − 8 cm long × 3 − 4 cm wide; fruits globose, 6 × 6 mm . . . . . . . . . W. fosteri (Hutch. & Dalziel) Jacq.-Fél.
11. Young branchlets robust, subquadrangular; leaf-blades 10 − 17 cm long × 5 − 8 cm wide; fruits globose, 10 – 15 mm
in diameter . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . W. reygaertii sensu Jacques-Félix (1983)
Young branchlets acutely quadrangular to narrowly quadrangular-alate; leaf-blades 5 − 13.5 (− 18) cm long × 3 − 6.5
(− 7) cm wide; fruits ellipsoid-oblong to ovoid or pyriform . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
12. Inflorescences on peduncles 3 – 6 mm long, shortly branched, 5 – 7-flowered, 1 – 1.5 cm long in total; flowers
on pedicels 1 – 2 mm long . . . . . . . . . . . . . . . . . . . . . . . . W. yangambensis (A. Fern. & R. Fern.) Jacq.-Fél.
Inflorescences sessile or on peduncles to 2 mm long, unbranched, 1 – 3-flowered, 0.5 cm long in total; flowers
sessile or on pedicels to 2 mm long . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
© The Board of Trustees of the Royal Botanic Gardens, Kew, 2018
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13. Anther connective gland conspicuous, elliptic in outline . . . . . . . . . . . . . . . . . . . . W. membranifolia (Hook. f.) Jacq.-Fél.
Anther connective gland vestigial . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . W. ngutiensis R. D. Stone
Warneckea ngutiensis R. D. Stone sp. nov. Type:
Cameroon, South West Province, Nguti region,
towards river Lowoa near edge of Banyang Mbo
Wildlife Sanctuary, 5°20.23'N, 9°28.41'E, alt. 250
m, forest understory, fls. & fr., 28 Nov. 2000,
Pollard 552 (holotype K [K000460176]; isotype
YA).
http://www.ipni.org/urn:lsid:ipni.org:names:77175882-1
Evergreen understorey shrub to 1.5 m tall. Branchlets
slender, the youngest quadrangular in cross section
and narrowly alate becoming terete with age; internodes 3 – 4 (– 4.7) cm long. Leaves on petioles 3.5 –
4 mm long, the petioles channelled on the adaxial
side. Blades subcoriaceous, dark green and shining on
the upper surface, paler beneath, elliptic in outline,
up to 13.5 cm long and 6.5 cm wide, base broadly
cuneate, acuminate at apex, the acumen slender and
1.5 – 2.5 cm long; midnerve and principal lateral
nerves impressed on the upper surface, prominent on
the lower, the lateral nerves diverging from the
midnerve at the base of the blade, curvilinear except
near the leaf apex where forming weak arches
between the junctions with the transverse veins;
secondary lateral nerves 1 pair, much thinner than
the principal laterals, intramarginal and weakly arched
for their entire length; transverse veins 8 – 12 pairs, of
about the same thickness as the secondary laterals,
somewhat prominent on the lower surface along with
the conspicuous network of smaller venules.
Inflorescence sessile, 3-flowered, borne at the thickened
nodes of older branches below the existing leaves;
bracts and bracteoles 1 – 1.5 mm long, lance-ovate,
cucullate. Flowers sessile or nearly so (if pedicels
present then very short and concealed by the
subtending bracts and bracteoles); hypantho-calyx
obconic, 2 × 2 mm, the margin spreading and
distinctly lobed, the lobes broadly triangular. Petals
violet, narrowly spatulate – unguiculate, 2 mm long
and 0.75 – 1 mm wide, at anthesis spreading to slightly
recurved. Stamens well exserted on slender violetcoloured filaments 4 mm long; anthers 1 mm long, the
connective yellow, ± straight to slightly incurved dorsally,
the oil-gland vestigial and appearing as a dark
discolouration between the middle and the extremity of
the connective. Style slender, 5 mm long. Fruit dark
purple at maturity, 8 mm long and 5 mm wide, crowned
by the persistent calyx. Fig. 1.
RECOGNITION. Differs from other species of Warneckea
sect. Strychnoides by the combination of inflorescences
sessile, flowering pedicels very short, and staminal oilgland vestigial (not conspicuously present on the
dorsal side of the anther connective).
SPECIMENS EXAMINED. CAMEROON. South West Province, Nguti region, towards river Lowoa near edge of
Banyang Mbo Wildlife Sanctuary, 5°20.23'N,
9°28.41'E, alt. 250 m, forest understory, fls. & fr., 28
Nov. 2000, Pollard 552 (holotype K [K000460176];
isotype YA).
HABITAT & ECOLOGY. Lowland evergreen forest; 250 m
alt.
CONSERVATION. Warneckea ngutiensis is assessed here as
Critically Endangered CR B1 + B2ab(iii) + D using the
IUCN (2012) criteria. This is because it is known from
a single location just to the south of the former
Banyang Mbo Wildlife Sanctuary (since downrated in
protected status) near the town of Nguti. Many
memecyloid species are both restricted in their range
and infrequent within it (Cheek pp. 212 – 222 in
Onana & Cheek 2011), and this is supposed by us to
be the case with W. ngutiensis. This is because, in 2
weeks’ botanising by numerous botanists at this
location in 2000, only one gathering was made of this
species. Further subsequent botanical surveys from the
same base near Nguti by botanists from the University
of Rostok, Germany led by Prof. Stefan Porembski
(pers. comm. to Cheek) and Prof. Bonaventure Sonké
of the École Normale Supérieure, University of
Yaoundé (pers. comm. to Cheek) have similarly not
produced any additional records of the species so far
as is known.
The only known site for Warneckea ngutiensis is within
the boundary of the area proposed as an oil palm
plantation by the U.S.A.-based company, Herakles
(http://www.greenpeace.org/usa/wp-content/uploads/
legacy/Global/usa/planet3/PDFs/
HeraklesCrimeFile.pdf., and https://www.google.co.uk/
?gfe_rd=cr&ei=JaTuVdz2FYnj8weqyIKIBQ&gws_rd=ssl#q=herakles+oil+palm+plantation,+cameroon both
downloaded 8 Sept. 2015). Although this operation was
reported as suspended in 2013 (http://
www.greenpeace.org/international/en/news/Blogs/
makingwaves/herakles-cameroon-palm-oil-project-startsto-/blog/45259/ downloaded 9 Sept. 2015), there are
concerns that it will be resurrected in the near future since
Herakles has continued its activities on the ground
(https://www.grain.org/article/entries/5037-communities-lose-out-to-oil-palm-plantations, downloaded 9
Sept. 2015). Therefore, there is every chance that all
known individuals of the species will become extinct when
clearing proceeds for the establishment of the plantation.
It is perfectly possible that the species also extends to the
© The Board of Trustees of the Royal Botanic Gardens, Kew, 2018
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Fig. 1. Warneckea ngutiensis. A habit, flowering branch; B detail of stem apex, leaf base and internode; C transverse section of stem
showing four wings — from B; D inflorescence, showing bracts and bracteoles; E single flower, detail of D; F flower cut open longitudinally
and flattened to show insertion of filaments and petals; G bract, adaxial surface, showing colleters-hairs; H petals; J – L anther with expanded
connective, oil gland absent, J outer surface, K inner surface, L side view; M fruit. All from Pollard 552. DRAWN BY ANDREW BROWN.
© The Board of Trustees of the Royal Botanic Gardens, Kew, 2018
KEW BULLETIN (2018) 73:12
north into the Banyang Mbo reserve where it might have
the prospect of protection. Yet equally it might extend
south and west of Nguti into the main part of the area
designated for plantation by Herakles. This area remains
relatively unsurveyed for plants, although it occurs within
the area of Tropical Africa with the highest density of wild
plant species, which occurs in SW Region Cameroon
(Cheek et al. 2001).
Even if a broad buffer area were created outside
the boundary of Banyang Mbo, there is a risk that
farmers displaced by the future plantation project will
take up land within it and so threaten the only known
locality of Warneckea ngutiensis. For these reasons we
consider the only known location for Warneckea
ngutiensis to be highly threatened, and the extent of
occurrence and area of occupancy of the species to be
4 km2, adopting the preferred IUCN (2012) 4 km2
grid cell.
Warneckea ngutiensis is also threatened because of
the low number of individuals recorded: no more than
five were thought to have been seen by Pollard (pers.
comm. to Cheek). In the Red Data Book of the Plants of
Cameroon (Onana & Cheek 2011), ‘Warneckea ngutiensis
ined.’ was first mentioned and considered to be
Critically Endangered. However, since it had not been
published, its threatened status could not be accepted
by IUCN at that time.
ETYMOLOGY. Named for the town of Nguti, the closest
settlement to the type location.
Discussion
Warneckea ngutiensis evidently belongs in W. sect.
Strychnoides, a monophyletic group of c. 24 species
distributed in Guinean-Congolian Africa (Stone &
Andreasen 2010). Amongst the species of this section,
the inflorescence dimensions are quite variable, as are
the size and position of the anther gland. On the one
hand there is a group of closely related species with
long peduncles and distinctly pedicellate flowers, e.g.
W. pulcherrima, W. austro-occidentalis and W. bequaertii
(De Wild.) Jacq.-Fél. On the other hand there are
several species with inflorescences sessile or subsessile
and with flowering pedicels also very short, e.g.
W. membranifolia, W. reygaertii, W. yangambensis, and
W. gilletii (De Wild.) Jacq.-Fél. In terms of the anthergland, there are several species in sect. Strychnoides
with the gland occupying 1=3 to 2=3 the length of the
connective, while in other species it is positioned near
the extremity of the connective, or even reduced and
punctiform e.g. W. sapinii (De Wild. ) Jacq.-Fél. as per
the description in Fl. Cameroun (Jacques-Félix 1983).
Within Warneckea sect. Strychnoides, the new species
W. ngutiensis seems closest to the above-mentioned
group of four species with sessile or subsessile
inflorescences and flowers. Of these there is only
one species, W. membranifolia, in which both the
Page 5 of 6 12
inflorescences and flowers can be fully subsessile as
in W. ngutiensis. Warneckea membranifolia is widespread
and common in intact evergreen forest in Cameroon,
but is clearly distinguished by having anthers with a
conspicuous oil-gland (vs gland vestigial and inconspicuous in W. ngutiensis).
Acknowledgements
The authors are grateful to the National Herbarium of
Cameroon-IRAD-MINRESI for permission to collect
specimens in Cameroon, to WCS Cameroon for
accommodation in the Banyang Mbo Research Station, and to Earthwatch Europe for supporting the
survey by sponsoring costs of the participants. The
Darwin Initiative also supported elements of this
survey. Janis Shillito typed the manuscript. Two
anonymous reviewers are thanked for comments on
an earlier version of the manuscript.
References
Cable, S. & Cheek, M. (1998). The Plants of Mt
Cameroon. A Conservation Checklist. Royal Botanic
Gardens, Kew.
Cheek, M. (2000). A synoptic revision of Ancistrocladus
(Ancistrocladaceae) in Africa, with a new species
from western Cameroon. Kew Bull. 55: 871 – 882.
____ (2003). A new species of Ledermanniella
(Podostemaceae) from western Cameroon. Kew Bull.
58: 733 – 737.
____ & Cable, S. (1997). Plant Inventory for conservation
management: the Kew-Earthwatch programme in
Western Cameroon, 1993 – 96. In: S. Doolan (ed.),
African Rainforests and the Conservation of Biodiversity,
pp. 29 – 38. Earthwatch Europe, Oxford.
____, Pollard, B. J., Darbyshire, I., Onana, J.-M. &
Wild, C. (2004). The plants of Kupe, Mwanenguba and
the Bakossi Mountains, Cameroon. A Conservation
Checklist. Royal Botanic Gardens, Kew.
____, Harvey, Y. & Onana, J.-M. (2011). The Plants of
Mefou Proposed National Park, Yaoundé, Cameroon. A
Conservation Checklist. Royal Botanic Gardens, Kew.
____, Mackinder, B., Gosline, G., Onana, J.-M. &
Achoundong, G. (2001). The phytogeography and
flora of western Cameroon and the Cross River-Sanaga
River interval. Syst. & Geogr. Pl. 71: 1097 – 1100.
____, Williams, S. & Etuge, M. (2003). Kupea
martinetugei, a new genus and species of Triuridaceae
from western Cameroon. Kew Bull. 58: 225 – 228.
____ & Onana, J.-M. (2011). Red Data Species in
Cameroon, a Guide for Secondary School Teachers. Royal
Botanic Gardens, Kew.
Darbyshire, I., Anderson, S., Asatryan, A., Byfield, A.,
Cheek, M., Clubbe, C., Ghrabi, Z., Harris, T.,
Heatubun, C. D., Kalema, J., Magassouba, S.,
McCarthy, B., Milliken, W., de Montmollin, B., Nic
© The Board of Trustees of the Royal Botanic Gardens, Kew, 2018
12
Page 6 of 6
Lughadha, E., Onana, J. M., Saıdou, D., Sarbu, A.,
Shrestha, K. & Radford, E. A. (2017). Important
Plant Areas: revised selection criteria for a global
approach to plant conservation. Biodivers. Conserv.
26: 1767 – 1800. https://doi.org/10.1007/s10531017-1336-6.
Gosline, G. & Cheek, M. (1998). A new species of
Diospyros (Ebenaceae) from Southwest Cameroon.
Kew Bull. 53: 461 – 465.
Harvey, Y., Pollard, B. J., Darbyshire, I., Onana, J.-M. &
Cheek, M. (2004). The Plants of Bali Ngemba Forest
Reserve. Cameroon. A Conservation Checklist, Royal
Botanic Gardens, Kew.
____, Tchiengue, B. & Cheek, M. (2010). The Plants of
the Lebialem Highlands, A Conservation Checklist. Royal
Botanic Gardens, Kew.
IUCN (2012). IUCN Red List Categories and Criteria:
Version 3.1, Second edition. IUCN, Gland and
Cambridge.
Jacques-Félix, H. (1983). Mélastomatacées, In: B. Satabié
& J.-F. Leroy (eds), Flore du Cameroun Vol. 24.
Délégation Générale à la Recherche Scientifique
et Technique, Yaoundé.
Litt, A. & Cheek, M. (2002). Korupodendron songweanum, a
new genus of Vochysiaceae from West-central Africa.
Brittonia 54(1): 13 – 17.
© The Board of Trustees of the Royal Botanic Gardens, Kew, 2018
KEW BULLETIN (2018) 73:12
Onana, J.-M. (2011). The Vascular Plants of Cameroon, A
Taxonomic Checklist with IUCN Assessments. Flore Du
Cameroun 39. Ministry of Scientific Research and
Innovation, Yaoundé.
____ & Cheek, M. (2011). Red Data Book of the Flowering
Plants of Cameroon. Royal Botanic Gardens, Kew.
Stoffelen, P., Cheek, M., Bridson, D. & Robbrecht, E.
(1997). A new species of Coffea (Rubiaceae) and notes
on Mt Kupe (Cameroon). Kew Bull. 52: 989 – 994.
Stone, R. D. (2006). Phylogeny of major lineages in
Melastomataceae, subfamily Olisbeoideae: utility of
nuclear glyceraldehyde 3-phosphate dehydrogenase (GapC) gene sequences. Syst. Bot. 31: 107 – 121.
____ & Andreasen, K. (2010). The Afro-Madagascan
genus Warneckea (Melastomataceae): molecular systematics and revised infrageneric classification.
Taxon 59: 83 – 92.
____, Ghogue J.-P. & Cheek, M. (2008). Revised
treatment of Memecylon sect. Afzeliana
(Melastomataceae-Olisbeoideae), including three new
species from Cameroon. Kew Bull. 63: 227 – 241.
____, ____ & Cheek, M. (2009). Warneckea austrooccidentalis, a new species from Cameroon and
Nigeria, and a re-evaluation of W. fascicularis var.
mangrovensis (Melastomataceae-Olisbeoideae). Kew
Bull. 64: 307 – 312.