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A taxonomic synopsis of unifoliolate continental African Vepris (Rutaceae)
with three new threatened forest tree species from Kenya and Tanzania
Martin Cheek1 & W.R. Quentin Luke2
1
Herbarium, Royal Botanic Gardens, Kew, Richmond, Surrey, TW9 3AE, UK. Corresponding
author. e-mail: m.cheek@kew.org
2
East African Herbarium, National Museums of Kenya, P.O. Box 40658, Nairobi, Kenya.
Summary. Descriptions and illustrations are presented for three new species to science, Vepris
udzungwa Cheek, V. lukei Cheek (both Udzungwa Mts, Tanzania) and V. robertsoniae Cheek & Q.
Luke (SE Kenyan kaya forests) in the context of a synoptic taxonomic revision, with an
identification key to all the known unifoliolate taxa of Vepris in continental Africa. The remaining
species are given skeletal taxonomic treatments (lacking descriptions). One widespread species in
montane eastern Africa is renamed as Vepris simplex Cheek because its previous name, Vepris
simplicifolia (Engl.)Mziray is predated by Vepris simplicifolia Endl. (basionym of Sarcomelicope
simplicifolia (Endl.)T.G. Hartley, a widespread species of Australia, Lord Howe and Norfolk
Islands, and of New Caledonia).
Conservation assessments are presented for all species, or provisional conservation assessments are
presented. Of the 13 taxa, 11 are considered threatened, of which six are VU, two EN and three CR,
of which two are possibly extinct globally in the Uluguru Mts of Tanzania although not yet Red
Listed on iucnredlist.org.
Key words Chemistry; Extinct; Kaya Forests of Kenya; Udzungwa; Uluguru; Usambara
Introduction
Three new Vepris species are described in the context of a synoptic treatment of the African
unifoliolate species. The research was supported by preparation for a taxonomic revision of African
Vepris by the first author, and of floristic work for conservation prioritisation in the surviving
forests of Kenya and Tanzania by the second author. The paper builds on the foundation laid for the
three western African unifoliolate species by Lachenaud & Onana (2021), and increases the number
of described unifoliolate Vepris species for continental Africa from 10 to 13. Unifoliolate Vepris
species are likely not a natural group, but may have arisen more than once from ancestral trifoliolate
species. Yet without a well-sampled phylogeny it is difficult to be certain.
Vepris Comm. ex A. Juss. (Rutaceae-Toddalieae), is a genus with 93 accepted species, 23 in
Madagascar and the Comores and 69 in Continental Africa with one species extending to Arabia
and another endemic to India (Plants of the World Online, continuously updated). The genus was
last revised for tropical Africa by Verdoorn (1926). Founded on the Flore du Cameroun account of
Letouzey (1963), nine new species were recently described from Cameroon (Onana & Chevillotte
2015; Cheek et al. 2018a; Onana et al. 2019; Cheek & Onana 2021; Cheek et al. 2022a), taking the
total in Cameroon to 24 species, the highest number for any country globally, followed by Tanzania
(16 species). The greatest concentrations of Vepris species in Cameroon are within the CrossSanaga Interval (Cheek et al. 2001) with 15 species of Vepris of which nine are endemic to the
Interval. The Cross-Sanaga has the highest species and generic diversity per degree square in
tropical Africa including endemic genera such as Medusandra Brenan (Peridiscaceae, Breteler et al.
2015; Soltis et al. 2007; Barthlott et al. 1996; Dalgallier et al. 2020). Much of this diversity is
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associated with the Cameroon Highland areas, different highlands each having a species of a genus
e.g. as in Kupeantha Cheek (Rubiaceae, Cheek et al. 2018b). By comparison, neighbouring Gabon
has just seven species of Vepris (Sosef et al. 2006) and just one species, Vepris lecomteana (Pierre)
Cheek & T. Heller is listed for Congo-Brazzaville (Plants of the World Online, continuously
updated).
In continental Africa, Vepris are easily recognised. They differ from all other Rutaceae because they
have digitately (1 – )3( – 5)-foliolate (not pinnate) leaves, and unarmed (not spiny) stems. The
genus consists of evergreen shrubs and trees, predominantly of tropical lowland evergreen forest,
but with some species extending into submontane forests and some into drier forests and woodland.
Vepris species are often indicators of good quality, relatively undisturbed evergreen forest since they
are not pioneers.
Species of Vepris in Africa extend from South Africa, e.g. Vepris natalensis (Sond.) Mziray, to the
Guinean woodland in the fringes of the Sahara Desert (Vepris heterophylla (Engl.) Letouzey).
Mziray (1992) subsumed the genera Araliopsis Engl., Diphasia Pierre, Diphasiopsis Mendonça,
Oricia Pierre, Oriciopsis Engl., Teclea Delile, and Toddaliopsis Engl. into Vepris, although several
species were only formally transferred subsequently (e.g. Harris 2000; Gereau 2001; Cheek et al.
2009; Onana & Chevillotte 2015). Mziray’s conclusions were largely confirmed by the molecular
phylogenetic studies of Morton (2017) but Morton’s sampling was limited, identifications appeared
problematic (several species appear simultaneously in different parts of the phylogenetic trees) and
more molecular work would be desirable. Morton studied about 14 taxa of Vepris, all from eastern
Africa. More recently Appelhans & Wen (2020) focussing on Rutaceae of Madagascar have found
that the genus Ivodea Capuron is sister to Vepris and that a Malagasy Vepris is sister to those of
Africa. However, the vast majority of the African species including all those of West and Congolian
Africa, remain unsampled leaving the possibility open for changes to the topology of the
phylogenetic tree when this is addressed.
Characteristics of some of the formerly recognised genera are useful today in grouping species. The
“araliopsoid” species have hard, non-fleshy, subglobose, 4-locular fruit with 4 external grooves; the
“oriciopsoid” soft, fleshy 4-locular syncarpous fruit; “oricioid” species are 4-locular and apocarpous
in fruit; the fruits of “diphasioid” species are laterally compressed in one plane, bilocular and
bilobed at the apex; while “tecleoid” species are unilocular in fruit and 1-seeded, lacking external
lobes or grooves. There is limited support for these groupings in Morton’s study,
Due to the essential oils distributed in their leaves, and the alkaloids and terpenoids distributed in
their roots, bark and leaves, several species of Vepris have traditional medicinal value (Burkill
1997). Burkill details the uses, essential oils and alkaloids known from five species in west Africa:
Vepris hiernii Gereau (as Diphasia klaineana Pierre), Vepris suaveolens (Engl.) Mziray (as Teclea
suaveolens Engl.), Vepris afzelii (Engl.) Mziray (as Teclea afzelii Engl.), Vepris heterophylla (Engl.)
Letouzey (as Teclea sudanica A. Chev.) and Vepris verdoorniana (Exell & Mendonça) Mziray (as
Teclea verdoorniana Exell & Mendonça) (Burkill 1997: 651 – 653). Research into the
characterisation and anti-microbial and anti-malarial applications of alkaloid and limonoid
compounds in Vepris is active and ongoing (e.g., Atangana et al. 2017), although sometimes
published under generic names no longer in current use, e.g. Wansi et al. (2008). Applications
include as synergists for insecticides (Langat 2011). Cheplogoi et al. (2008) and Imbenzi et al.
(2014) respectively list 14 and 15 species of Vepris that have been studied for such compounds. A
review of ethnomedicinal uses, phytochemistry, and pharmacology of the genus Vepris was recently
published by Ombito et al. (2020), listing 213 different secondary compounds, mainly alkaloids and
furo- and pyroquinolines, isolated from 32 species of the genus, although the identification of
several of the species listed needs checking. However, few of these compounds have been screened
for any of their potential applications. Recently, Langat et al. (2021) have published three new
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acridones and reported multi-layered synergistic anti-microbial activity from Vepris gossweileri
(I.Verd.)Mziray, recently renamed as Vepris africana (Hook.f ex Benth.) Lachenaud & Onana
(Lachenaud & Onana 2021). There is no doubt that new compounds will continue to be discovered
as chemical investigation of Vepris species continues.
Materials and Methods
This taxonomic study is based on herbarium specimens predominantly at EA, BM and K, field
observations in Guinea, and Republic of Congo by the first author and field observations of live
material in Kenya and Tanzania by the second author. All specimens seen are indicated “!”. The
specimens were mainly collected using the patrol method as indicated e.g. in Cheek & Cable
(1997). Herbarium citations follow Index Herbariorum (Thiers et al. continuously updated),
nomenclature follows Turland et al. (2018) and binomial authorities follow IPNI (continuously
updated). Material of the new species was compared morphologically with material of all other
African Vepris, principally at K, but also using material and images from BM, EA, BR, FHO, G,
GC, HNG, P and YA. Herbarium material was examined with a Leica Wild M8 dissecting
binocular microscope fitted with an eyepiece graticule measuring in units of 0.025 mm at maximum
magnification. The drawing was made with the same equipment using a Leica 308700 camera
lucida attachment. The description was made following the format of Cheek et al. (2022) using
terms from Beentje & Cheek (2003). Specimen location data is given as on the label of the
specimens, understanding that the units formerly termed “Districts” in Kenya and Tanzania are
currently termed Counties.
For the extinction risk assessment, points were georeferenced using locality information from
herbarium specimens.). The conservation assessment was made using the categories and criteria of
IUCN (2012), EOO was calculated with GeoCat (Bachman et al. 2011).
Taxonomic Results
KEY TO THE UNIFOLIOLATE AFRICAN SPECIES OF VEPRIS
1.Leaves opposite at apex of stem; leaflets not articulated with petiole; fruit 4-loculed. W. Africa
from Guinea-Conakry to Liberia………………………………………………………1. V. laurifolia
1.Leaves always alternate; leaflets articulated with petiole; fruit 1- or 2-loculed. Central to eastern
Africa………………………………………………………………………………..…………...2
2.Stems hairy (visible at stem apex with x10 hand-lense)............................................................3
2.Stems glabrous (not visible at stem apex with hand-lense)........................................................5
3. Stems with hairs dense; stems sparsely lenticellate (<20% cover); leaf apex
acute or acuminate; petiole mostly >0.6 cm long....................................................................4
3. Stems with hairs sparse, erect, stems densely (>50% in patches) lenticellate, leaf apex
rounded; petiole 0.3 – 0.6 cm long. Tanzania, Udzungwa Mts.............2. V. udzungwa sp.nov.
4. Stems minutely puberulous; petiole (0.3 – )1 cm long; lateral nerves 20+ on each side of the
midrib; Mozambique......................................................................................3. V. drummondii
4. Stems densely long-hairy; petioles 1.25 – 2.5 cm long; lateral nerves c. 10 – 15 on each side of
the midrib. Uluguru Mts Tanzania…………………………………………….4. V. mildbraediana
5. Petioles winged. Tanzania, Udzungwa Mts............................................... 5. V. lukei sp. nov.
5. Petioles canaliculate to cylindric. Ethiopia to Angola...........................................................6
6. Leaves smelling of bad fish when live (crushed) or dried; petiole 0.5 – 1.8( – 2.8) cm long;
<300 m. alt. S.E. Kenya..................................................................6. V. robertsoniae sp. nov.
6. Leaves smelling of Citrus when live (crushed) or lacking scent; petiole mostly >(1.5 – ) 3 cm
long (except V. eugeniifolia and V. amaniensis in E Africa, and (W. Africa) V. africana) >300 m
alt.......................................................................................................................................................7
7. Inflorescence glabrous; stamens 8 in male flowers (4 – 7 in V. amaniensis) …………………..8
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7. Inflorescence hairy (hairs often minute); stamens 4 in male flowers ……………..…………....11
8.Fruits when ripe black; northern Angola…………………………………………..7. V. welwitschii
8.Fruits orange or red when ripe; E. Africa……………………………….……………………….9
9. Leaves ovate, 3.5 – 9 cm long. Somalia to Tanzania……………………………8. V. eugeniifolia
9. Leaves elliptic, 11 – 29 cm long. Tanzania…………………………..…………………………10
10. Leaves leathery; petiole terete at apex; inflorescence paniculate, 9 cm long, few-flowered;
stamens about twice as long as petals. Tanzania, Uluguru Mts………..………9. V. sp. A of FTEA
10. Leaves papery; petiole canaliculate at apex; inflorescence racemose 0.9 – 4( – 5) cm long;
stamens shorter than petals. Tanzania, Usambara Mts…..………………………10. V. amaniensis
11.Lateral nerves 16 – 23 on each side of the midrib. S. Tomé, Gabon-Angola…11. V. africana
11.Lateral nerves <14 on each side of the midrib. E Africa……………………………………12
12. Fruit asymmetric at base; pedicel 1 – 6 mm long. Kenya….12. V. hanangensis var. unifoliolata
12. Fruit symmetrical; pedicel mostly <1 mm long. Ethiopia, Kenya,
Tanzania……………………………………………………………….………………13. V. simplex
1. Vepris laurifolia (Hutch. & Dalziel) O. Lachenaud (Lachenaud & Onana 2021: 112). Type:
Guinea, Ninia, Talla Hills, 17 Feb. 1892, Scott-Elliott 4086 (Holotype BM barcode
BM000798360!). (Fig. 1)
Garcinia laurifolia Hutch. & Dalziel (1927: 236)
Vepris felicis Breteler (1995: 131; Hawthorne & Jongkind 2006: 704). Type: Liberia, Central
Province, c. 5 km SE of Zuole fl. 2 Apr. 1962, J.J.F.E. de Wilde & Voorhoeve 3754 (Holotype
WAG; isotypes A, B, BR, K barcode K000800952!, P)
DISTRIBUTION. Guinea-Conakry, Sierra Leone, Liberia, Ivory Coast
REPRESENTATIVE SPECIMENS EXAMINED. Guinea-Conakry. Guinée-Maritime. Frigiya
village, about 20 km NE of Madina Oula, fl. 29 Apr. 2012, Cheek et al. 16600 (HNG!, K!); After
Kouria (on Coyah to Kindia road), beyond town at foot of table mts, along valley and up stream to
Forest Patch 20 at head, 1 Oct. 2015, st. Cheek 18224 (HNG!, K!); Guinée Forestiere, Seredou
Village, fl. 14 Feb. 2014, P.K. Haba (HNG, K!, WAG); Yomou prefecture. A Tayiébah, au village
Kilikpala, Forêt Classée de Diécké, st. 15 Sept. 2015, P.M. Haba 899 (HNG, K !).
HABITAT. This shrub is known from lowland evergreen forest, usually associated with water
courses (possibly because other areas have been cleared). The altitudinal range is 80 – 624 m. In
the field notes of several specimens it is described as being found in 'forest relics' suggesting that it
only occurs in patches of intact 'primary' forest and is absent from secondary forest. Plants occur as
scattered individuals at low density; they appear to be dioecious, female flowers are larger and
fewer than male flowers. Pollinators are unknown. Fruits are 1–2 cm diameter, four-lobed orange
berries, probably primate-dispersed (Cheek 2017).
CONSERVATION STATUS. Vepris laurifolia was only known from 18 individuals in Sierra
Leone, but five of these are known to have been destroyed in recent years (hydroelectric dam
flooding) with two probably destroyed (due to agriculture in the area) and six more are due to be
lost in the next 1–10 years due to infrastructure developments (hydroelectric dam, transport
corridor). Although only 11–13 surviving individuals are documented, it is possible that as many as
50–100 individuals may be found elsewhere, but intact forest habitat for this species only occurs as
scattered remnants and is threatened with clearance for agriculture. Even in these scattered islands,
the species is mostly absent (M. Cheek pers. obs. 2012–2016, Guinea; X. van der Burgt pers. obs.
2009–2016, Sierra Leone). It is also absent, or extremely rare, from most of Liberia where most of
the surviving forest in West Africa remains. Botanical inventory work there over many years by C.
Jongkind has not discovered this species (C. Jongkind pers. comm. to M. Cheek 2014). None of the
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Fig. 1. Vepris laurifolia. Photo showing habit of flowering plant (Cheek 16600, HNG, K) in habitat
near Madina Oula, Republic of Guinea near the border with Sierra Leone, in 2012. Photo by M.
Cheek.
large national parks (e.g. Tai National Park, Gola Rainforest National Park) are known to support it,
despite botanical inventory effort. The species was assessed as Critically Endangered (CR) under
criterion C2a(i) since less than 250 mature individuals are thought to exist and there is a continuing
decline in the number of mature individuals, with less than 50 individuals in each subpopulation
(Cheek 2017). In Guinea the species is included in two Tropical Important Plant Areas,
Kounounkan and Ziama (Couch et al. 2019).
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PHENOLOGY. Flowers mainly in April & May. Fruit in Sept.
ETYMOLOGY. Named for the resemblance of the leaves to those of the genus Laurus (Lauraceae)
VERNACULAR NAMES. Foh-foh-tae (fide Mamadou Camara of Oure Kaba cited in Cheek et al.
16600). No uses are recorded.
NOTES. Vepris felicis was named by Breteler (1995) based on the Liberian specimen (J.F.F. E. de
Wilde 3754, type specimen), the specimens collected in Guinea in 1937 near Mt. Benna (JacquesFelix 2096 for from whom the species is named) and another specimen collected in 1954 near Mt.
Kakoulima (Schnell 7568). Since the species was not named until 1995, it did not feature in the
Rutaceae of Flora of West Tropical Africa (Keay 1958) and so is not mentioned in either Flore de la
Republique de Guinée (Lisowski 2009) nor Flore de la Cote-D'Ivoire (Ake Assi 2001), both of
which are based on the Flora of West Tropical Africa. Lachenaud and Onana (2021) recently
discovered that Garcinia laurifolia was an earlier and unexpected synonym of V. felicis. The
name G. laurifolia, was originally published in Clusiaceae, probably due to the opposite leaves and
poor state of the type collection (Scott-Elliott 4806 from Ninia, Talla Hills, Guinea). Lachenaud and
Onana (2021) have compared the types and there is no doubt that G. laurifolia is identical to V.
felicis and since the epithet laurifolia is earlier and still available in Vepris it takes precedence,
hence their publication of the new combination. The specimens we refer to above are additional to
those given in Lachenaud & Onana (2021).
Vepris laurifolia is unusual among unifoliolate Vepris in that at the apex of flowering stems, the
leaves are opposite (not alternate) and in that the leaflet is not articulated with the petiole, further
the fruits are 4-locular (in other unifoliolate species they are 1 or 2-locular), with four widely
separated style bases. This shrub is so unusual in its genus that flowering specimens in the field
have been misidentified as Rinorea (Violaceae). However, the translucid spots usual in Rutaceae
can be found using a lens, young leaves and bright light (Cheek 2017). This species should be a
priority for molecular phylogenetic analysis since it is so morphologically anomalous.
2.Vepris udzungwa Cheek sp. nov. Type: Tanzania, Udzungwa Mountains National Park, Camp
357 – pt 358, 07.4° S, 36.37° E, 1980 m, fr. 12 Oct. 2002, Luke et al. 9109 (holotype K barcode
K000875153! isotypes EA! NHT!, MO!). (Fig. 2)
Evergreen tree 5 – 8 m tall, lacking scent when dried, densely branched. Leafy stem internodes (0.6
– )0.8 – 1.4( – 3.3) cm long, 1 – 2 mm diam., at the most distal leafy node, minutely puberulent
when young, hairs white, simple, patent, c. 0.05 mm long, covering c. 10% of surface, glabrescent,
epidermis rapidly becoming white-grey, densely (c. 50% of surface) lenticellate; lenticels raised,
white, longitudinally elliptic, 0.75 x 0.5 mm, with a longitudinal midline groove. Leaves coriaceous,
± concolorous, dark green when live (Luke et al. 6895, K) drying green-yellow below, green-brown
above, upper surface glossy, lanceolate-elliptic, less usually narrowly elliptic 3.7 – 6.8( – 7.3) x 1.6
– 2.5 cm, apex rounded, base broadly, convexly acute to subrounded, margin slightly revolute when
dried; secondary nerves 7 – 8( – 10) on each side of the midrib, arising at c. 60° from the midrib,
intersecondary nerves conspicuous, raised, forming a reticulum, tertiary and quaternary nerves not
raised, less conspicuous; oil glands inconspicuous on upper surface, black and conspicuous on
lower surface, (0 – )2 – 3( – 4) per mm². Petiole articulated at apex, plano-convex, 0.3 – 0.6( – 0.9)
cm long, 1.5 mm wide, margins with minute patent wings c. 0.4 mm wide, widest at articulation
with blade, generally narrowing towards base, glabrous, crater-like glands inconspicuous.
Inflorescences known from fruiting and post-anthetic material only, female inflorescences axillary
racemes, 1 – 3( – 5)-flowered, inflorescence axis 3 – 10 mm long, glabrous. Bracts at base of
pedicel, isodiametric, c. 4 x 4 mm, glabrous. Pedicels 1.5 mm long, glabrous. Sepals 4, broadly
triangular, c. 0.5 x 0.75 mm, glabrous. Petals not seen. Stamens (female flowers) 4, c. 1 mm long,
filaments dorsiventrally flattened, tapering from base to apex, anthers orbicular, c. 0.3 mm diam.
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Fig. 2 Vepris udzungwa A. habit, fruiting branch; B. young stem showing hairs; C. older stem,
showing dense lenticels and persistent hairs; D. leaf, adaxial surface; E. abaxial leaf surface
showing conspicuous black oil gland dots; F. stem node and immature infructescence with leaf,
showing winged petiole; G. fruit, side view, showing basal and apical asymmetry (stigma
arrowed); H. transverse section of fruit showing seed. Scale bars: A = 5 cm; D = 1 cm; E-H = 5
mm; C = 2 mm; B = 1 mm. A-E, G&H from Luke et al. 9109; F from Luke et al. 8639. Drawn
by Andrew Brown.
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Fruit ellipsoid to obovoid, slightly laterally compressed, 10 – 11 x 8 x 7 mm, asymmetric at base
and apex, both pedicel and style inserted sublaterally on opposing sides, apex rounded, base
truncate; style elliptic, flat, 1 mm wide; surface with irregular, longitudinal ribs, glabrous, surface
oil glands inconspicuous; fruit wall 0.75 mm thick, endocarp not detected; uniloculate, 1-seeded.
Seed ellipsoid 9 – 9.5 x 6.5 x 5.5 mm, seed coat dark brown, thinly leathery; embryo white,
cotyledons equal, surface oil gland pits colourless.
RECOGNITION. Vepris udzungwa differs from V. lukei Cheek in the lateral nerves of the leafblade 7 – 8( – 10) on each side of the midrib (not 22 – 28), leaf apex rounded (not acuminate), and
from all other E. African (Uganda, Kenya, Tanzania) unifoliolate species except V. mildbraediana in
the hairy stems (not glabrous) and in the fruit asymmetric at both apex and base.
DISTRIBUTION. Tanzania, endemic to the summits of the Udzungwa Mts.
SPECIMENS EXAMINED. TANZANIA. Udzungwa Mountains National Park, Camp 357 – pt
358, 07.41° S, 36.37° E, 1980 m, fr. 12 Oct. 2002, Luke et al. 9109 (holo. K barcode K000875153!;
iso: EA! NHT!, MO!); ibid, Luhomero Mt, camp 132 – 134, 07.47° S, 36.33° E, 2100 m, st. 3 Oct.
2000, Luke et al. 6895 (EA!, K, 000875155!); ibid, above exit gully, 07.40° S, 36.36° E, 2100 m,
imm. fr. 1 June 2002, Luke et al 8639 (EA! K barcode K000875154!, NHT!, MO!).
HABITAT. Interface of montane evergreen forest with wet montane “grassland”; 1980 – 2100 m.
alt. with Asplenium rutifolium (Bergius) Kunze (Aspleniaceae), Vincetoxicum coriaceum (Schltr.)
Meve & Liede (Apocynaceae), Psychotria cryptogrammata E.M.A. Petit (Rubiaceae), Diodella
sarmentosa (Sw.) Bacigalupo & E.L. Cabral (Rubiaceae), Pauridiantha hirsuta Ntore (Rubiaceae),
Geranium arabicum Forssk. (Geraniaceae), Crotalaria lukwangulensis Harms (Leguminosae),
Coleus schliebenii (Mildbr.) A.J. Paton (Labiatae), Cyphostemma masukuense (Baker) Wild & R.B.
Drumm. ssp. ferrugineo-velutinum Verdc. (Vitaceae), Cucumis oreosyce H. Schaef. (Cucurbitaceae),
Peperomia retusa (L.f.) A. Dietr. (Piperaceae), Ranunculus multifidus Forssk.(Ranunculaceae),
Eriocaulon transvaalicum N.E. Br. ssp. tofieldifolium (Shinz) S.M. Phillips (Eriocaulaceae),
Satyrium crassicaule Rendle (Orchidaceae), Clutia abyssinica Jaub. & Spach (Peraceae), Cyanotis
barbata D. Don (Commelinaceae), Fuirena stricta Steud. ssp. chlorocarpa (Ridl.) Lye
(Cyperaceae).
CONSERVATION STATUS. Vepris udzungwa is known from two specimen-sites at a single
threat-based location, the well-protected (Q. Luke pers. obs.) Udzungwa Mountains National Park.
The area of occupation is estimated as 8 km2 using the preferred IUCN cell-size of 4 km2. Extent of
occurrence using Geocat is 17 km2.Therefore, we assess the species as Vulnerable VU D2, since
although there are no immediate threats, should parts of the protected area be de-gazetted as has
been proposed or has happened for other such areas in Tanzania (Qin et al. 2019) the risk is that the
species would soon become lost to habitat clearance.
PHENOLOGY. Immature fruits in June, mature fruits and growth pulse (flush) in Oct.
ETYMOLOGY. Taking the name of the mountain range and National Park in which the species
was discovered and to which it appears to be unique.
VERNACULAR NAMES & USES. None are known.
NOTES. Vepris udzungwa, apart from V.mildbraediana, is unique among all east African (Uganda,
Kenya, Tanzania) unifoliolate Vepris species in the hairy stems (Fig. 1B), and also in the fruits
which are not only asymmetric at the base (as in e.g. V. hanaganensis) but also at the apex, the style
being subapical (Fig. 1G). In addition, alone among these species it has longitudinally irregularly
ribbed wrinkled fruits (Fig. 1G).
Luke et al. 6895 had previously been determined as “?” and numbers 8639 and 9109 as “Vepris sp.
(=Luke 6895)” by Kaj Vollesen indicating that in annotating the three specimens Vepris sp. cf.
eugeniifolia, he recognised them to represent a possible distinct, unplaced taxon.
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Vepris udzungwa, since it occurs at 2000 m. alt, has oblong-elliptic leaves 3.7 – 6.8 x 1.6 – 2.5 cm,
which lack an acumen, and in which the fruits are subglobose, is most likely to be confused with the
widespread Vepris eugeniifolia (Tanzania – Somalia) and V. simplicifolia (N. Malawi – Ethiopia). It
differs from both in the puberulent stems (versus glabrous) and in the both basally and apically
asymmetric fruit (versus symmetric), short (0.3 – 0.6( – 0.9) cm long), winged petioles (versus
longer, canaliculate or cylindrical petioles).
An unusual feature of V. udzungwa is the very densely lenticellate stems. Parts of the older stems
can be more than 50% covered in lenticels, while in most other Vepris species the older stems are
only sparsely lenticellate. It is possible that V. udzungwa shares a recent common ancestor with V.
lukei which occurs at the same mountain range, at a lower altitudinal band. However, these two
species are morphologically unlikely to be confused (see under the last species, below).
Numerous other species have been relatively recently discovered and are restricted or are largely
restricted to the Udzungwa Mts. e.g., Polyceratocarpus askhambryan-iringae A.J. Marshall & D.
M. Johnson (Annonaceae, Marshall et al. 2016), Trichila lovettii Cheek (Meliaceae, Cheek 1989).
Ancistrocladus tanzaniensis Cheek & Frim.-Møll. (Ancistrocladaceae, Cheek et al. 2000; Cheek
2000), Lukea triciae Cheek & Gosline (Annonaceae, Cheek et al. 2022b); Uvariopsis lovettiana
Couvreur & Q. Luke (Annonaceae, Couvreur & Q. Luke 2010); Toussaintia patriciae Q. Luke &
Deroin (Annonaceae, Deroin & Q. Luke 2005); Vernonia luhomeroensis Q. Luke & Beentje
(Asteraceae, Luke & Beentje 2003); Lijndenia udzungwarum R.D. Stone & Q. Luke
(Melastomataceae, Stone & Luke 2015)
3. Vepris drummondii Mendonça (1961: 84; 1963: 204); Type: Zimbabwe “S. Rhodesia, Melsetter
Distr., Glencoe Forest Reserve, slopes of Mt Pene”, fl. 24 Nov. 1955, Drummond 4995 (K holotype
barcode K000199467!, isotypes PRE barcode PRE0688690!, SRGH barcode SRGH0000250-0!)
DISTRIBUTION. This species is restricted to the southern foothills of the Chimanimani
Mountains of Zimbabwe and Mozambique, and nearby Mt Pene and Tarka Forest Lands in
Zimbabwe. Its presence in Mozambique was only confirmed in 2015, although there were earlier
potential records (Timberlake et al. 2016). A record from Mt Mulanje in Malawi (specimen at
Harare Herbarium) is considered to be erroneous and is omitted (Darbyshire et al. 2017)
REPRESENTATIVE SPECIMENS EXAMINED. Zimbabwe, Melsetter Distr., On Chambuka
River bank above the hydroram, Tarka Forest Reserve, fl. Nov. 1970, Goldsmith 35/70 (K!, SRGH,
WAG); ibid. Haroni River, confluence of Haroni and Timbiri Rivers., fr. April 1969, Goldsmith
38/69 (BR, K!, SRGH, WAG).
HABITAT. This small puberulous shrub c. 0.7 m tall, is found in the deep shade of mixed
evergreen forest, sometimes associated with rivers and gulleys, at low to mid-altitudes, 300 – 1,600
m.
CONSERVATION STATUS. Vepris drummondii is known from only 11 collections, collected
between 1955 and 2015 and is listed as Vulnerable under criteria B1ab(iii)+2ab(iii) with an EOO of
69 km² and an AOO of 32 km² based on known occurrence data (Darbyshire et al. 2017). Although
this may be a slight under-estimate, total AOO is unlikely to exceed 100 km². Several of the
localities for this species are within Forest Reserves, for example Glencoe Forest Land in
Zimbabwe, although these are managed for commercial forest production rather than for
biodiversity and so do not guarantee protection. At Maronga in Mozambique much of the lowland
forest has been cleared outside of the Trans-Frontier Conservation Area core zone and there is also
significant artisanal gold mining activity along the Mussapo River west of Maronga, which has
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almost certainly resulted in riverine forest loss there. However, there is still intact forest suitable for
this species within the core protected area at Maronga (Darbyshire et al. 2017). The species is
considered secure at both the Chimanimani National Park (Timberlake et al. 2016) and at Glencoe
in Zimbabwe.
PHENOLOGY. Flowering in November, fruiting in April.
ETYMOLOGY. Named for the late Robert (Bob) Drummond (1924 – 2008), a life-long Africa
botanist and botanical collector who collected the type specimen of this species and who was
curator and a stalwart of the SRGH herbarium in Harare until the end of his life (Timberlake et al.
2017).
VERNACULAR NAMES & USES. None are recorded.
NOTES. Vepris drummondii is unlikely to be confused with any other species since it is the only
unifoliolate Vepris in the Flora Zambesiaca area (Mozambique, Malawi, Zambia, Zimbabwe,
Botswana, Caprivi strip of Namibia). The other species are all trifoliolate. It is similar to V.
mildbraediana of the Uluguru Mts of Tanzania, but that species has longer and denser hairs on the
axes, and the partial-peduncles are only c. 2 mm long and few-flowered, while in V. drummondii
they are much more fully developed. Nonetheless these two may be sister species to each other.
“The shiny thin skinned deep red fruits resemble small cherries. Two to three seeds each fruit,
green” (Goldsmith 38/69)
4.Vepris mildbraediana G.M. Schulze (in Mildbraed 1934:192; Kokwaro 1982: 23). Type:
Tanzania, “Bezirk Morogoro, Uluguru Gebirge, Nordwestseite, Nebelwald”, fl. 8 Nov. 1932,
Schleiben 2933 (Holotype B destroyed; isotype BR barcode BR000000627300!).
DISTRIBUTION. Tanzania, Uluguru Mts
REPRESENTATIVE SPECIMENS EXAMINED. Only known from the type specimen.
HABITAT. Submontane forest; 1860 m alt.
CONSERVATION STATUS. Vepris mildbraediana does not appear on iucnredlist.org. Since the
collector of the type specimen stated that it was “isolated” we can deduce that only a single plant
was seen. Given threats to habitats in the Uluguru Mts (Ndang’ang’a et al. 2007) and the record of
only a single individual (and certainly less than 50) despite multiple surveys for plants (but not
targeting this species so far as we know) we provisionally assess this species as CR B1(ab(iiii)+B2ab(i-iii), D.
PHENOLOGY. Only known in flower in November. Fruits unknown.
ETYMOLOGY. Named for Mildbraed (Gottfried Wilhelm Johannes Mildbraed (1879 – 1954)), a
heroic botanist who despite being captured in then German Kamerun in the first world war, losing
all his specimens collected, as spoils of war to the British (they were sent to K), and being
imprisoned in France 1914 – 1919, continued collecting specimens in tropical Africa (1907 – 1928)
and as a taxonomist identifying and publishing his discoveries and those of others. He collected in
Cameroon, Tanzania, Burundi and Rwanda among other places.
VERNACULAR NAMES. None are known.
NOTES. Kokwaro (1982) treated Vepris mildbraediana as an “Insufficiently known species”,
stating that he had not seen the type nor any other specimens so named, and that Bruce 510, which
he described as Vepris sp. A, “has many similar characters (and is from the same locality) except for
its paniculate inflorescence. On the other hand, V. mildbraediana may be a synonym of V.
ngamensis if its inflorescence is a raceme as stated.” Happily, thanks to JStor Global Plants and the
African Plants Initiative (reference?), while the holotype at B is destroyed, an isotype at BR was
detected and is available as a high quality image.
https://plants.jstor.org/stable/10.5555/al.ap.specimen.br0000006273002?searchUri=genus%3DVepri
s%26species%3Dmildbraediana
It shows that the type specimen is densely covered in long, patent, yellow-brown, hairs, persistent
on the stem for 5 – 6 nodes, also on the petioles, abaxial midrib and inflorescence axis. No other
unifoliolate East African species described has such dense indumentum. Vepris udzungwa is the
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only other African unifoliolate Vepris described that has hairy stems but those are only present at the
first internode, and the hairs are white, appressed, sparse (c. 10% coverage of the surface) and
minute (0.05 mm long). Vepris mildbraediana has a panicle, but the partial-peduncles are only c. 2
mm long, unlike the raceme reported for V. ngamensis. Vepris sp. A of FTEA, apart from being
glabrous has more gracile inflorescence axes and the stamens are twice as long as the petals (in
Vepris mildbraediana the axes are stout, and the petals as long as the anthers). There is no doubt
that Vepris mildbraediana is a distinct species
5. Vepris lukei Cheek sp. nov. Type: Tanzania, Udzungwa Mountains National Park, 07.40°S,
36.39°E, Camp 366-pt 367 1800 m alt., fr. 15 Oct. 2002, Luke W.R.Q. & P.A, et al. 9166 (holotype
K barcode K000875455!; isotypes: EA!, NHT!, MO!). (Fig. 3)
Evergreen tree 2 – 5 m tall, when dried smelling of dried fish. Leafy stems drying black, glossy,
terete, 2 – 5 mm diam., internodes 4 – 26 mm long, increasing in length from the beginning of the
flush (growth pulse), the main axis with 7 – 11 nodes per flush, growth of different flushes
separated by 1 – 7 cm of naked stem; lenticels lacking, with fine longitudinal lines, glabrous.
Leaves thinly coriaceous, ± concolorous, drying grey-green, glossy, narrowly oblong-elliptic, 6.5 –
13.7 x 1.8 – 3.7 cm, acumen 0.4 – 1.1 cm long, base broadly acute, margin undulate, slightly
revolute, secondary nerves 22 – 28 on each side of the midrib, arising at c. 80° from the midrib,
brochidodromous, forming a looping inframarginal nerve c. 2 mm from the margin; intersecondary
nerves well developed, tertiary and quaternary nerves raised, forming a conspicuous reticulum on
the lower surface; gland dots sparse, and barely detectable in transmitted light, only slightly
translucent; concolorous so inconspicuous in reflected light except as minute raised spots on the
abaxial surface, glabrous. Petiole articulated at apex, 2.5 – 48 mm long, variable in length; those
first produced in a season longest, becoming successively shorter in successive nodes, planoconvex, c. 1 x 1 mm in section, the adaxial surface flat, the margins with a slender wing 0.5 mm
wide, held at c. 45° from the vertical plane of the petiole axis, and bearing orbicular crater-like
glands 0.2 – 0.25 mm diam., 2 – 8 mm apart. Inflorescences known from fruiting material only,
female inflorescences 1 – 2 per stem, single, axillary in the leaf axils of the current season’s growth.
Bracts 2, basal, opposite, connate, each forming a cupular pseudo-calyx 1 mm diam., c. 0.5 mm
deep, glabrous. Pedicel 1( – 2) x 0.75 mm, glabrous. Sepals 4, triangular, c. 1 x 1 mm, becoming
indurated in fruit, glabrous. Fruit ripening orange, cylindric-ellipsoid, 1-seeded, 15 – 17 x 7 – 10
mm, stigma remains subglobose, apex flattened, 0.5 mm long, 0.75 mm diam., surface with raised
black oil glands 0.2 mm diam., 2 – 3 per mm², glabrous. Pericarp 0.5 mm thick, endocarp
vascularised, adhering to epicarp. Seed the same shape and slightly smaller than fruit, testa
pellicular, brown; cotyledons 2, equal, the outer surface white, pitted with oil glands 0.1 mm diam.
RECOGNITION. Vepris lukei Cheek is similar to Vepris robertsoniae, differing in the 1-fruited
infructescence, fruit surface with conspicuous, large black, raised oil glands, and fruit apex rounded
(vs 2 – 5-fruited, surface with inconspicuous minute or absent oil glands, fruit apex acute to slightly
rostrate), petioles winged, 0.25 – 4.8 cm long (vs canaliculate, (0.35 – )0.5 – 1.8( – 2.8) cm long),
secondary nerves 22 – 28 each side of the midrib, stem epidermis black (vs secondary nerves 8 –
15 each side of the midrib, stem epidermis becoming dull white). Additional diagnostic characters
can be found in table 1.
DISTRIBUTION. Tanzania, Udzungwa Mts.
SPECIMENS EXAMINED. TANZANIA. Udzungwa Mountains National Park, 07.40°S,
36.39°E, Camp 366-pt 367 1800 m alt., fr. 15 Oct. 2002, Luke, W.R.Q. & P.A et al. 9166 (K holo!;
iso EA!, MO!, NHT!); Ndundulu Forest Reserve, 07.47°S, 36.39°E, Camp 589 1540m alt., fr. 6
Sept. 2004, Luke et al. 10343 (EA!, K!, MO!).
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Fig. 3. Vepris lukei A. habit, fruiting branch; B. large leaf and attachment to stem; C. base of leafblade, articulation and winged petiole showing gland, together with transverse section of petiole to
show wings; D. abaxial surface of leaf-blade showing reticulate quaternary nerves and
inconspicuous oil glands; E. mature fruit showing raised black oil glands on surface.
Scale-bars: graduated double bar = 5 cm; double bar = 1 cm; graduated single bar = 5 mm. A & D
from Luke et al. 9166; B, C, & E = Luke & Luke et al. 10343. Drawn by ANDREW BROWN.
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HABITAT. Submontane forest; 1540 – 1800 m alt. Associated species (identifications of Luke et al.
specimens collected with Vepris lukei): Hypoestes forskaolii (Vahl) R. Br. ssp. forskaolii,
Sclerochiton uluguruensis Vollesen (Acanthaceae), Isolona linearis Couvreur, Monodora globiflora
Couvreur (Annonaceae), Vincetoxicum anomalum (N.E. Br.) Meve & Liede (Apocynaceae),
Diospyros sp. Luke & Luke 9165, 9166 (Ebenaceae), Erythrococca sanjensis Radcl.-Sm.
(Euphorbiaceae), Streptocarpus kirkii Hook.f. (Gesneriaceae), Jasminum abyssinicum DC.
(Oleaceae), Ixora scheffleri K. Schum. & K. Krause ssp. scheffleri, Pauridiantha paucinervis
(Hiern) Bremek. ssp. holstii (K. Schum.) Verdc. Psychotria cryptogrammata E.M.A. Petit, Tarenna
roseicosta Bridson, Tricalysia aciculiflora Robbr. (Rubiaceae), Vepris stolzii I. Verd., Zanthoxylum
gilletii (De Wild.) P.G. Waterman (Rutaceae), Dracaena fragrans (L.) Ker Gawl. (Dracaenaceae),
Aframomum laxiflorum Lock (Zingiberaceae).
CONSERVATION STATUS. Vepris lukei is known only from the two specimens cited above, both
shown on Google earth as being within the Udzungwa Mts National Park (although the southern
site, formerly in the Ndundulu Forest Reserve is now officially the West Kilombero Nature Reserve
contiguous with the National Park, Q. Luke pers. obs.), separated by c. 13 km. The protection level
of this National Park is high currently, and so threats do not exist for this species at present (Q.
Luke pers. obs. 2002 – 2004). However, with only a single location, a low number of individuals
(only two specimens were seen despite hundreds of specimens being collected over two years by
Luke and associates, and before and since by other botanical field workers) and an area of
occupation estimated as 8 km2 using the preferred IUCN cell-size of 4 km2 (extent of occurrence
cannot be calculated with only two points), this species would have a significant risk of extinction
(from clearance of the forest habitat for agriculture as has been widespread in E Arc Forests) were
the current excellent management levels to be lowered or the area to be partly degazetted as a
National Park as has been proposed for other protected areas in Tanzania e.g. Serengeti National
Park and Selous Forest Reserve (Qin et al. 2019). Since the species fits the IUCN (IUCN Standards
and Petitions Committee 2022) definition of VU D2 “of a species not declining, but ..characterized
by an acute restriction in their area of occupancy or in their number of locations thereby rendering
them particularly susceptible to a plausible threat” we assess Vepris lukei as VU D2 (Vulnerable).
PHENOLOGY. Leaf flushing in September. Fruiting in September and October, flowering
unknown.
ETYMOLOGY. Named for William Richard Quentin Luke, better known as Quentin Luke
(1952-), lead collector of all known specimens of Vepris lukei, and the most prolific living field
botanist in East Africa. He is a Kenyan botanist and is Research Associate of the East African
herbarium (EA). Full biographical and bibliographical information can be found in Polhill & Polhill
(2015: 276 – 277). He has brought to light previously unknown species from across Africa e.g., in
eastern Democratic Republic of Congo: Keetia namoyae O. Lachenaud & Q. Luke (Lachenaud et
al. 2017) and from Mali and Guinea the only endemic African Calophyllum, C. africanum Cheek &
Q. Luke (Cheek & Luke 2016; Couch et al. 2019). He has discovered numerous new species of
plants especially in Kenya and Tanzania, such as the incredible spectacular Tanzanian tree acanth
Barleria mirabilis I.Darbysh. & Q.Luke (Darbyshire & Luke 2016). He has also collected and
described many other novel plant species from Tanzania and Kenya. More than ten
species are named for him, e.g. Keetia lukei Bridson (Rubiaceae, Bridson 1994), including also the
Tanzanian species Cola quentinii Cheek (Cheek & Dorr 2007) and Cola lukei Cheek (Cheek 2002).
Most recently Lukea Gosline & Cheek, a new genus to science has been named in his honour
(Cheek et al. 2022b).
VERNACULAR NAMES. None are known.
NOTES. Luke et al. 10343 had previously been identified as Vepris robertsoniae ined., and Luke &
Luke 9166 as “Vepris sp., not matched” by Kaj Vollesen in 2004.
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Luke et al. 10343 has new shoots with expanding leaves, and also the leaves from the previous
season’s growth. These show a progressive reduction in length of the petiole during a season’s
growth. The first formed petiole is 48 mm long, the second formed 43 mm long, then 38 mm, 30
mm, 25 mm, 22 mm, 14 mm, 10 mm, 5 mm, and finally at the end of the growth pulse, before
dormancy, 2.5 mm long.
Vepris lukei has many similarities with V. robertsoniae and for this reason they may share a recent
common ancestor and may well be sister species. Both species smell of fish when dried, have
numerous parallel secondary nerves, crater glands on the petiole, are glabrous except for the sepal
margins, lack panicles and nectar discs. For these reasons it is logical that material of V. lukei was
formerly named as V. robertsoniae. However apart from ecology and geography, the two species
differ in several key morphological characters (Table 1) and there is no doubt that they are distinct.
Vepris robertsoniae
Vepris lukei
Stem epidermis (dried material) Pale brown, ageing dull white
Black, persisting black with age
Number of secondary nerves on 8 – 15
each side of the midrib
22 – 28
Visibility of oil gland dots on
abaxial leaf-blade surface
Conspicuous, black
Inconspicuous, concolorous
with blade.
Petiole length
(0.35 – )0.5 – 1.8( – 2.8) cm
0.25 – 4.8 cm
Petiole shape
Canaliculate, wings absent
Winged
Fruit apex
Acute to slightly rostrate
Rounded
Fruit surface: oil glands (dried
material)
Inconspicuous, minute,
concolorous or absent
Conspicuous, large black,
raised.
Infructescence
2 – 5-fruited
1-fruited
Habitat
Lowland semi-evergreen forest, Submontane evergreen forest
usually on limestone; 0 – 290m on crystalline rocks; 1540 –
alt.
1800m alt.
Geography
S.E. Kenya (Lamu, Kwale,
Kilifi Districts)
Udzungwa Mts, Tanzania
Table 1. Diagnostic characters separating Vepris robertsoniae from Vepris lukei
Vepris lukei is unusual amongst E African unifoliolate Vepris species in possessing winged petioles.
All other species have canaliculate or terete petioles. It also is unusual in the extreme high number
of secondary nerves, 22 – 28 on each side of the midrib – resembling a Calophyllum. Further, it is
unique in this group in the highly reduced female inflorescences which appear to be 1-flowered.
Examination of immature fruiting specimens gives no indication that they bore more than one
flower. Yet this species remains known from only two collections, and male and female flowers at
anthesis remain to be obtained.
The geographical and ecological disjunction between the two very similar and probably sister species,
one at low altitude in the coastal forests of SE Kenya, the other at high altitude in the Eastern Arc
Mountains of Tanzania, is seen in several other genera, such as Lukea, with L. quentinii Gosline &
Cheek in Kenyan coastal forest, and L. triciae in the Udzungwa Mts (Cheek et al. in press),
Ancistrocladus Wall. with A. tanzaniensis Cheek & Frim.-Møll. in the Udzungwas and A.
robertsoniorum J.Léonard in the Kenyan coastal forests (Cheek et al. 2000, Cheek 2000), also in the
genus Afrothismia with A. mhoroana Cheek in the Ulugurus and A. baerae Cheek in Kenyan coastal
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forests (Cheek 2004b; Cheek 2006; Cheek & Jannerup 2006). Numerous other taxa are restricted to
the Eastern Arc Mts of Tanzania and the Kenyan Coastal Forests, which together are referred to as
EACF (see discussion).
New plant species are still steadily being discovered for science and published from Tanzania, other
recent examples being Mischogyne iddii Gosline & A.R. Marshall (Annonaceae, Gosline et al.
2019), Hibiscus hareyae L.A.J.Thomson & Cheek (Malvaceae, Thomson & Cheek 2020),
Inversodicraea tanzaniensis Cheek (Podostemaceae, Cheek et al. 2020a) and Keetia davidii
(Rubiaceae, Cheek & Bridson 2019),
6. Vepris robertsoniae Q. Luke & Cheek sp. nov. Type: Kenya, Kwale District, Marenji, 50 m,
fl.,18 Dec. 1990, W.R.Q. Luke & S.A. Robertson 2679 (holotype K barcode K000875137!; isotypes
EA!, MO!, UPPS!). (Fig. 4 – 7).
Vepris robertsonae Q.Luke ined. (Luke 2005: 62)
Small evergreen tree or shrub (1.5 – )2 – 6m tall, dried specimens smelling of dried fish. Leafy
stems drying glossy brown-green, finely longitudinally wrinkled, terete, internodes (0 – )0.8 – 4( –
9.3) cm long, 2 – 4( – 5) mm diam. at the lowest leafy node, becoming pale, whitish grey, lenticels
rare, sparse, white longitudinally elliptic, 0.3 – 1.4 x 0.2 – 0.4( – 0.5) mm Leaves thickly
coriaceous, drying grey-green above, almost concolorous, but the lower surface slightly brown,
elliptic, rarely slightly ovate-elliptic, (3.75 – )7 – 13.2( – 18.4) x (1.5 – )3 – 5.1( – 6.35) cm, acumen
short and broad, (0 – )0.4 – 1.2( – 1.8) cm long, sometimes absent, base broadly acute or rounded;
margin slightly revolute when dry; secondary nerves 8 – 15 on each side of the midrib, arising at 40
– 50° from the midrib, brochidodromous, forming a looping inframarginal nerve c. 2 mm from the
margin; intersecondary nerves as well developed as secondary nerves, tertiary nerves reticulate, the
nerves raised; gland dots clear and bright in transmitted light, about 1( – 3) per mm², in reflected
light conspicuous, black, but not raised on the abaxial surface, 0.2 mm diam., (0 – )1 – 2( – 4) per
mm²; glabrous. Petiole articulated at apex, longest produced at start, shortest at end of growth
season, canaliculate, (0.35 – )0.5 – 1.8( – 2.8) cm long, 1 – 1.5 mm wide, the ventral groove slitlike, margins with scattered crater-like glands. Inflorescences 8 – 15 per leafy stem, 4 – 10flowered, racemose, axillary, 0.5 – 1.4 cm long, peduncle 1 – 1.5 mm long, bracts 0.1 mm long.
Male flowers with pedicel c. 0.5 mm long. Sepals 4, quadrangular, 0.3 – 0.6 x 0.8 – 1 mm, glabrous
apart from a few simple marginal hairs 0.05 mm long. Petals 4, elliptic-oblong, 3.5 x 1.5 – 1.75
mm, apex slightly acuminate. Stamens 4, c. 3 mm long, filaments 1.5 mm long; anthers ellipsoid
1.5 – 1.75x 1 mm, glabrous. Disc absent. Pistillode 1 x 0.6 mm, glabrous. Female flowers with
pedicels (2.5 – )3 – 4 mm long, dilated at apex, sepals 4 as in male flowers. Petals oblong-elliptic,
2.5 – 2.8 x 1.8 mm, apex obtuse. Staminodes 8, c. 1 mm long, 4 shorter than others, with vestigial
anthers. Ovary obovoid, c. 2 mm long, proximal third 1 mm diam., unilocular, distal two-thirds 1.5
mm diam., apex retuse, style c. 0.3 mm long, widening from base to apex, stigma peltate, c. 1 mm
diam. Infructescence 2 – 5-fruited. Fruits yellow-orange (live), 1-seeded, ellipsoid or ovoidellipsoid 8 – 11.5 x 4 – 5.5( – 7.5) mm, apex weakly rostrate or acute, rostrum c. 1 mm long, base
rounded, pericarp leathery, thin, surface lacking oil glands, glabrous. Seed ellipsoid-ovoid c. 9 x 5
mm, encased in endocarp. Endocarp cartilaginous, translucent, laced with a network of flattened
vascular bundles, brown; seed-coat membranous; cotyledons equal, white, surface black, pitted with
oil glands c. 0.1 mm diam.
RECOGNITION. Similar to Vepris eugeniifolia (Engl.) I. Verd., differing in the elliptic (rarely
slightly ovate-elliptic) leaf-blades (vs ovate); flowers single along the rhachis in the inflorescences
(vs glomerules along the rhachis); fruits ovoid-ellipsoid or ellipsoid, apex acute or slightly rostrate
(vs globose, apex rounded). Additional diagnostic characters are given below in the notes and in
table 2.
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Fig. 4. Vepris robertsoniae Habit of fruiting shrub, Base Titanium nursery 15 April 2019 . Photo by
W.R.Q. Luke
Fig. 5. Vepris robertsoniae Close up of male flowers, note the four stamens, cultivated plant in Base
Titanium nursery 28 May 2021. Photo by W.R.Q. Luke
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Fig. 6. Vepris robertsoniae Close up of female flowers, 11 Nov. 2020, Base Titanium nursery. The
Eight staminodes are concealed. Photo by W.R.Q. Luke
DISTRIBUTION. Coastal Kenya: Lamu, Kilifi and KwaleCounties.
SPECIMENS EXAMINED. KENYA. Lamu District, Lunghi Forest Reserve, 35 m, st., 1 Dec.
1988, W.R.Q. Luke & S.A. Robertson 1539 (EA!, K000875135!); Kilifi District, between Dzitsoni
& Jaribuni, 150 m, fl., 21 Feb. 1989, W.R.Q. Luke & S.A. Robertson 1670 (EA!, K000875136!);
Kilifi District, Mangea Hill, 450 m, fl., 25 March 1989, W.R.Q. Luke & S.A. Robertson 1824 (EA!,
K000875143!); Kilifi District, Mangea Hill (Sita), 290 m, fr., 24 Mar 1989, W.R.Q. Luke & S.A.
Robertson 1771 (EA!, K000875144!, MO!); Kilifi District, Kaya Jibana, SW slope, 200 m, fl., 14
Dec. 1990, W.R.Q. Luke & S.A. Robertson 2642 (EA!, two sheets: K000875145!, K000875146!);
Kwale District, Marenji, 50 m, fl.,18 Dec. 1990, W.R.Q. Luke & S.A. Robertson 2679 (holo.
K000875137!; iso. EA!, MO!, UPPS!); Kwale District, Mwachi Forest Reserve NW corner and
down to Mwachi river, 0.359° S 39.32° E, 30-80 m, fl.,17 May 1990, S.A. Robertson & W.R.Q.
Luke 6187 (EA!, two sheets: K000875138!, K000875139!, MO!); Kwale District, Mwaluganji
Forest Reserve (including Kaya Mtae), 0.405° S 39.27° E, 200 – 300 m, fl., 15 Nov. 1989, S.A.
Robertson & W.R.Q. Luke 6044 (EA!, K000875140!) Kwale District, Gongoni Forest, 30m, st., 3
June 1990, W.R.Q. Luke & S.A. Robertson 2395 (EA!, K000875141!); Kwale District, Gongoni
Forest, 30 m, fl., 9 June 1990, W.R.Q. Luke 2415 (EA!, K000875142!); Kwale District, Gongoni
Forest, 30 m, fl., 9 June1990, W.R.Q. Luke 2416 (EA!, two sheets: K000875147!, K000875148!,
UPS!); Kwale District, Diani forest, 0.420° S 39.34° E, 5 m, fl., 29 Aug. 1993, S.A. Robertson 6852
(EA!, K000875149!).
HABITAT. Lowland semi-evergreen forest, usually (always?) on limestone; 5 – 200 ( – 290) m alt.
Associated species (identifications of Luke et al. specimens collected with Vepris robsertsoniae):
Ecbolium amplexicaule S. Moore, Thunbergia stelligera Lindau, Trichaulax mwasumbii Vollesen
(Acanthaceae), Psilotrichum majus Peter (Amaranthaceae), Solanecio angulatus (Vahl) C. Jeffrey
(Compositae), Dictyophleba lucida (K. Schum.) Pierre (Apocynaceae), Diospyros shimbaensis F.
White (Ebenaceae), Triaspis mozambica A. Juss. (Malpighiaceae), Eugenia verdcourtii Byng
(Myrtaceae), Afrocanthium kilifiense (Bridson) Lantz, Cladoceras subcapitatum (K. Schum. & K.
Krause) Bremek., Coffea pseudozanguebariae Bridson, Coptosperma supra-axillare (Hemsl.)
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Fig. 7. Vepris robertsoniae A. habit, flowering branch; B. base of leaf-blade showing articulation
with canaliculate petiole and glands; C. abaxial surface of leaf-blade showing surface with black
oil glands; D. male inflorescence; E. male flower bud; F. male flower with stamen and petal
removed to show pistillode; G. female inflorescence; H. female flower; I. longitudinal section of
female flower showing unilocular ovary with a single pendulous ovule. A, B, D-F from Luke et al.
2679; C from Luke et al. 1670; G-I from Robertson 6852; J, K Luke et al. 1771; Drawn by
ANDREW BROWN.
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Degreef, Didymosalpinx norae (Swynnerton) Keay, Pavetta crebrifolia Hiern var. crebrifolia,
Psydrax faulknerae Bridson, Rothmannia manganjae (Hiern) Keay, Rytigynia parvifolia Verdc.,
Tricalysia pallens Hiern (Rubiaceae), Haplocoelum inoploeum Radlk. (Sapindaceae), Rinorea
squamosa (Tul.) Baill. ssp. kaessneri (Engl.) Grey-Wilson (Violaceae), Cyphostemma
zimmermannii Verdc. (Vitaceae), Zamioculcas zamiifolia (Lodd.) Engl.(Araceae), Angraecum teres
Summerh., Calyptrochilum christyanum (Rchb.f.) Summerh. (Orchidaceae)
CONSERVATION STATUS. Vepris robertsoniae is known from nine locations with an extent of
occurrence of 7825 km2 and area of occupation of 88 km2. Threats include degradation of habitat,
such as cutting of poles. Therefore the species was assessed as Vulnerable, VU
B1ab(i,ii,iii,iv,v)+2ab(i,ii,iii,iv,v) (Musili et al. 2020).
PHENOLOGY. Flowering Nov.- June (-Aug.), fruiting in March-June.
ETYMOLOGY. Named for Mrs Anne Robertson of Kenya, pioneering collector of plants and early
champion of the conservation of Kenya’s coastal forests where her studies resulted in the discovery
of plant species several others of which, apart from Vepris robertsoniae are named for her,
including Barleria robertsoniae I.Darbysh. (Darbyshire et al. 2010) and Psydrax
robertsoniae Bridson (Bridson 1991). Anne Robertson also produced a checklist of the Seychelles
Islands, collecting there also, and is commemorated there by.Cynanchum robertsoniae Liede (Liede
1995). Finally, she is commemorated with her late husband Ian by the coastal Kenyan forest liana
species Ancistrocladus robertsoniorum J. Léonard (Ancistrocladaceae, Léonard 1984; Cheek
2000).
VERNACULAR NAMES. None recorded.
NOTES. Vepris robertsoniae is most likely to be confused with Vepris eugeniifolia (see table 2)
which also occurs at low altitudes on coral rock in S.E. Kenya, is probably sympatric, but which is
much more common and widespread (Tanzania to Somalia).
Vepris eugeniifolia
Vepris robertsoniae
Scent of dried leaves
Odourless
Dried fish
Leaf-blade shape
Ovate or lanceolate
Elliptic (rarely slightly ovateelliptic)
Leaf-blade dimensions
3.5 – 9 x 2 – 4.2 cm
(3.75 – )7 – 13.2( – 18.4) x (1.5
– )3 – 5.1( – 6.35) cm
Inflorescence length
1 – 3( – 8.5) cm
0.5 – 1.4 cm
Number of styles (both female
and male flowers) and locules
2
1
Fruit shape
Globose, apex rounded
Ellipsoid or ovoid-ellipsoid,
apex slightly rostrate or acute
Petiole
Cylindric (terete)
Canaliculate
No. secondary nerves each side 6 – 8( – 9)
of the midrib
8 – 15
No. stamens in male flowers
4
8
Table 2. Diagnostic characters separating Vepris robertsoniae from Vepris eugeniifolia.
Characters for Vepris eugeniifolia taken from Kokwaro (1982).
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Apart from both species being unifoliolate and glabrous, with similar gland dots they also share the
key character formerly ascribed in FTEA to distinguish Vepris in the former narrow sense: 8
stamens. But this number of stamens are only present in the female flowers of V. robertsoniae: the
male flowers have four stamens. Characters separating the two species are given in Table 2. The
two are easily separated vegetatively since V. robertsoniae has a canaliculate (not terete) petiole, the
blade has 8 – 15 lateral nerves (not 6 – 8( – 9)) on each side of the midrib. The base of the blade is
broadly acute or rounded, the margin at that point convex or straight, while in V. eugeniifolia it is
usually concave. In dried specimens of the last species the blade folds along the midrib, exposing
the abaxial surface in old leaves on a sheet, while those of V. robertsoniae remain flat.
Vepris robertsoniae has also been confused with V. lukei. See under the last species for a discussion
of their affinities and for diagnostic characters separating them (Table 1).
Numerous other species with a similar range to Vepris robersoniae, also threatened and restricted to
a set of Kenyan coastal Kaya forests, have been steadily documented in recent decades. Examples
include Uvariodendron dzomboense Dagallier, W.R.Q. Luke & Couvreur (Kaya Dzombo, EN
B1ab(iii)+2ab(iii)) and Uvariodendron schmidtii W.R.Q. Luke, Dagallier & Couvreur
(Longomwagandi, likely VU)(both Annonaceae, Dagallier et al. 2021), Croton kinondoensis
G.W.Hu, V.M.Ngumbau & Q.F.Wang (Kaya Kinondo, likely CR, Euphorbiaceae, Ngumbau et al.
2020), Saintpaulia ionantha H.Wendl. ssp. rupicola (B.L. Burtt) I. Darbysh. (Cha Simba, CR A2ac,
B2ab(i,ii,iii,iv,v), Gesneriaceae, Darbyshire 2006), Keetia lukei Bridson (Kaya Jibana and Gongoni
F.R, EN B1ab(iii)+2ab(iii), Rubiaceae, Bridson 1994) and Premna mwadimei Ngumbau & G.W. Hu
(Cha Simba, CR B1ab(iii)+2ab(iii), Labiatae, Ngumbau et al. 2021).
Cultivated plants, collected as seedlings from Gongoni Forest Reserve in July 2014, began to flower
and fruit when they attained about 1.2 m tall after four to five years (observations from the Base
Titanium nursery in coastal Kenya by the second author). The planting medium used was a sandy
soil mix with coir and manure. Flowering occurs April-June, Nov. & Dec, fruiting April -June, and
December.
7. Vepris welwitschii (Hiern) Exell (1929: 148; Exell & Mendonça 1951: 272; Figueiredo & Smith
2008: 155 ). Type: Angola, “in montibus petrosis supra Tandambando”, fr. Nov. 1854, Welwitsch
471 (Lectotype LISU, barcode LISU206243!, syntypes BM barcode BM00798355!, LISU barcode
LISU206244!, PRE barcode PRE0601859-0! “Zenzo do Golungo”)
Glycosmis welwitschii Hiern (1896: 115)
Vepris gossweileri I. Verd. (1926: 399) non Mziray (1992: 72). Angola. Type: Serra do SocolloUndui, between Ambriz and Lifuni River, “Loanda, Cazengo”, fr. 11 Dec. 1907, Gossweiler 4895
(Holotype K, barcode K000199522!; isotypes COI barcode COI COI00040965!, K barcode
K000199523!).
DISTRIBUTION. Angola. The species is only known from a few specimens in Bengo and Cuanza
Norte provinces in northwestern Angola. It is known from four localities (Lachenaud & Onana
2021).
REPRESENTATIVE SPECIMENS EXAMINED. Angola, Luanda: Icala e Bengo – Macchias de
Catete, fr. 1929, Gossweiler 9173 (COI barcode COI00040964!)
HABITAT. Vepris welwitschii is restricted to xerophytic vegetation on limestone outcrops up to 800
m in altitude (Lachenaud & Onana 2021).
CONSERVATION STATUS. Vepris welwitschii was assessed as Near Threatened by Timberlake
(2021b), stating that it is not widely distributed and that only historic records are available since it
was last recorded in 1921. Timberlake stated that it has an extent of occurrence (EOO) of 8,368
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km2 and an area of occupancy (AOO) of 20 km2 calculated from the four known collecting localities
and that there appears to have been land cover change from agriculture and settlement at some of
the localities that could threaten the species. In contrast to Timberlake, Lachenaud & Onana (2021)
assess the species as Endangered EN B2ab(iii) citing an EOO of 14,092 km2, and AOO of 12 km2
and an expected decline due to habitat clearance for e.g. charcoal. The second assessment appears to
better reflect the extinction risk status of the species.
PHENOLOGY. Flower buds and immature fruits in September, mature fruits in October
(Lachenaud & Onana 2021).
ETYMOLOGY. Named for the Austrian, Friedrich Welwitsch (1806 – 1872), the most famous
botanical collector of specimens in Angola, who collected the original specimens from which the
species was described. He is also commemorated by the genus Welwitschia Hook.f. (Hooker 1863).
VERNACULAR NAMES & USES. None are known
NOTES. Vepris welwitschii a tree to 6 m tall, is most likely to be confused, and indeed has been,
with V. africana, the only other unifoliolate species of the genus that occurs in Angola. The two can
be distinguished using the characters cited above under the second species and in the key to species.
Most notably Vepris welwitschii has black fruit, not orange or red as is usual in the genus.
Lectotypification, synonymy and delimitation of this species was expertly performed by Lachenaud
& Onana (2021). However, they opted to choose as lectotype a syntype at LISU for which there is
no evidence that Bentham, credited author of the name, had seen. The syntype at BM does not have
this deficiency. They also point out that this species remains incompletely known e.g. open flowers
are not available.
8.V. eugeniifolia (Engl.) I. Verd. (Verdoorn 1926: 399; Kokwaro 1982: 17; Beentje 1994: 371;
Thulin 1999:177; Friis 1992: 184, fig. 115; Luke 2005: 62). Type: Tanzania, Usambara Mts,
Mashewa (« Mascheua »), 500 m, fl. Aug. 1893, Holst 8869 (B holotype probably destroyed;
isotypes BM, G barcode G00445210!, HBG barcode HBG510346!, K barcode K000199492!, M
barcode M-0110250!, S sheet number 08-9780!)
Toddalia simplicifolia var. eugeniifolia Engl. (Engler 1895: 228)
? Teclea gracilipes Engler (1917: 308). Type: Tanzania, Uzaramo Distrct, Stuhlmann 1894 (B
holotype probably destroyed)
Aegelopsis alexandrae Chiov. (Chiovenda 1932: 50). Type: Somalia, Giubia, isola Touata di
Alexandra, July 1931, Zozzi 327, (isotype K barcode K000199447!)
Teclea alexandrae (Chiov.) Senni (1935: 82)
DISTRIBUTION. Ethiopia, Somalia, Kenya, Tanzania
REPRESENTATIVE SPECIMENS EXAMINED. ETHIOPIA. 12 km NE of Telte towards
Brindi and Yavello, 1150 m alt., fr. 24 Nov. 2010, Friis et al. 13882 (ETH, K!); SOMALIA. 20 km
from Fanoole barrage. Jess site 54. st. 31 Jan. 1988, Deshmukh in Jess 435 (K!); Summit of Bur
Juqalalan, 300 – 630 m, fr. 30 Feb. 1982, Beckett 1700 (K!). KENYA. Northern Prov., Dandu, fr. 11
April 1952, 800 m, Gillett 12761 (EA, K!); West of Malindi, N bank of Galana River, st. 13 Feb
1953, Woodley in Bally 8586 (K!); Makueni Distr., Kibwezi FR, 975 m alt., fr. Luke 14376, EA,
K!), Kilifi, fl. 23 Dec. 1936, Moggridge 221 (EA, K!). TANZANIA. Genda-Genda South, fr. 27
June 1982, Hawthorne 949 (EA, FHO, K!); Handeni Distr., Kwa Mkono, 600 m, fr. 20 Feb.
1980, Archbold 2737 (DSM, EA, K!)
HABITAT. Coastal forest and semi-evergreen shrubland on coral rag or normal soil, or at higher
altitudes in Acacia-Commiphora woodland, rainfall ranges 500/1000 mm p.a. (e.g. Friis 1992: 185);
0 – 630( – 1827) m alt.
CONSERVATION STATUS. Vepris eugeniifolia does not appear on iucnredlist.org, but from its
wide range and numerous sites it is likely to be assessed as Least Concern.
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PHENOLOGY. Fruits June, Nov.-Dec. in Ethiopia, Feb. in Somalia, Apr.-Aug. in Kenya &
Tanzania. Flowering Dec.-Feb. in Ethiopia, May(-July) in Somalia, Dec.-April, July-Oct. in Kenya
and Tanzania.
VERNACULAR NAMES & USES. Agnio golet (Zozzi 327, K!), filfil owliyi (Deshmukh in Jess
435, K!), rehdo (Beckett 1700, K! all Somali, Somalia); Mwaowa (Wakulu) leaves boiled in water
and administered orally for canine complaints( Kenya, Kilifi Moggridge 221, K!), root bark used in
the preparation of arrow poison (W Malindi, Woodley in Bally 8586, K!)
NOTES. Not rarely confused with the usually higher altitude V. simplex especially at mid to low
altitudes in Kenya and Ethiopia. While in Ethiopia V. simplex grows at altitudes of 1900 – 2000 m
in Podocarpus forest, Vepris eugeniifolia grows in drier and lower habitats e.g. 1100 – 1400 m alt.,
in Acacia-Commiphora woodland, and in fact can survive in drier habitats than any other African
unifoliolate Vepris, witness that it is the only unifoliolate species to occur in Somalia (Thulin 1999).
The leaves are acuminate (usually rounded in V. simplex) and their size range is smaller, although
the largest leaves of V. eugeniifolia can exceed the smallest of V. simplex. The flowers are extremely
different, those of V. simplex being twice the size and having four not eight stamens, the females
with one style not two, and the fruits of V. simplex are smaller 3 – 4(–5) mm diam., subsessile,
drying black or orange, while those of V. eugeniifolia are 6 – 8 mm diam., drying with a white waxy
layer on 4 – 6 mm long pedicels.
9. V. sp. A of FTEA Kokwaro (1982:18); Mziray (1992: 78)
DISTRIBUTION. Tanzania, Morogoro Distr.
SPECIMENS EXAMINED. Tanzania, Morogoro Distr., Uluguru Mts, Bunduki, fl. 10 Jan 1935,
Bruce 510
HABITAT. Submontane forest c. 1700 m alt.
CONSERVATION STATUS. Vepris sp.A of FTEA has not been formally named and therefore
does not appear on iucnredlist.org. Provisionally it should be regarded as Critically Endangered CR
D since only a single plant is known at a site that has threats (Ndang’ang’a et al. 2007). Forest loss
at Uluguru Mts has been concentrated in the habitat of Vepris sp.A of FTEA (see discussion).
PHENOLOGY. Flowering in January, fruits unknown.
VERNACULAR NAMES. None are recorded
NOTES. Kokwaro (1982: 18) recognised this entity and stated “The specimen is somewhat similar
to Teclea amaniensis except the stamens are clearly 8. It is however, inadequate to formally
describe a new species. It is also close to Vepris ngamensis but here the inflorescence is a panicle.
See also V. mildbraediana, p. 23”. Treated by Mziray (1992: 78) as an “Insufficiently known
taxon”. This entity appears to be a most distinct and yet undescribed species.
10. Vepris amaniensis (Engl.) Mziray (pro parte 1992: 70)
Types: Tanzania, Amani, Engler 565 (Syntype, B destroyed); Warnecke 516 (Syntype B, destroyed);
Neotype proposed here Tanzania “Tanganyika Terr., Amani”, 5 April 1922, Salmon 171 K barcode
K000593352!; EA)
Teclea amaniensis Engl. (Engler 1905: 244; Kokwaro 1982: 24 pro parte)
Vepris ngamensis Engl. ex Verdoorn (1926: 399); Kokwaro (1982: 18). Type: Tanzania, E.
Usambara Mts, Amani, Engler 565 (holotype B destroyed; neotype selected here: Tanzania
“Tanganyika terr., Amani, 4 April 1919, Salamani bin Kilwa G6172 (Neo. K barcode K000593351!;
isoneo EA)). synon. nov.
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DISTRIBUTION. Tanzania, Muheza Distr., Usambara Mts at Amani and Bulwa.
SPECIMENS EXAMINED. TANZANIA. Muheza Distr. Amani, Engler 565 (B syn. destroyed);
ibid. Warnecke 516 ( B syn., destroyed); ibid. Amani, 5 April 1922, Salmon 171 (K neo.!, EA
isoneo.); ibid Amani, 4 April 1919, Salamani bin Kilwa G6172 (K neo.!, EA isoneo); ibid. Amani,
Urwald, fr. 22 July 1911, Grote AH 3416 (K!); E. Usambara, Bulwa, Ukundo, imm. fr. 27 Aug.
1980, Kibuwa 5342 (K!); ibid. old fl., fr. 27 Aug. 1980, Kibuwa 5343 (K!); ibid, just below Amani,
2900’, fl. 20 March 1950, Verdcourt 122 (K!, two sheets); ibid., Amani Forest, near the guest house,
fr. 3 Aug. 1986, Lovett, Ellis, Keeley 869 (K!, MO).
HABITAT. Vepris amaniensis is a 0.5 – 3 m tall shrub in evergreen forest with Myrianthus,
Allanblackia (Clusiaceae), Memecylon cogniauxii (Melastomataceae, Verdcourt 122),
Cephalosphaera usambarensis (Myristicaceae), Anisophyllea obtusifolia (Anisophylleaceae,
Lovett et al. 869); 900 – 1000 m alt.
CONSERVATION STATUS. Timberlake (2021a) in assessing the extinction risk of V. amaniensis
states:.Some of the forests from which Vepris amaniensis is recorded, particularly in Tanzania, are
under threat of clearance for small-scale and subsistence agriculture. The extent of occurrence
(EOO) is calculated at 210,887 km2 and the minimum area of occupancy (AOO) is 104 km2. As
there are only nine recorded locations the species is assessed as Vulnerable VU B2ab(ii,iii,v).
However, it has recently been discovered (see Notes below) that this species is restricted to near
Amani and Bulwa in the Usambara Mts, with a far smaller AOO and EOO, and so will merit reassessment, likely as EN.
PHENOLOGY. Flowering in March and April, fruits in July and August.
ETYMOLOGY. Meaning “from Amani”, referring to the origin of the original specimens which
were collected at or near Amani in the Usambara Mts of then German E Africa, Tanganyika, now
Tanzania.
VERNACULAR NAMES & USES. None are recorded.
NOTES. While finalising the key and skeletal species accounts for this paper, the first author found
that the specimens assigned to this species at K, although concordant as a whole with the
description in Kokwaro (1982), contained more than one species. Most of the material was not in
agreement with the description in the original protologue of Engler (1905), nor the description by
Verdoorn (1926), which appears based on Engler’s description (although is less precise). It seems
that between the time of Verdoorn (1926), who only cited Warnecke 516K, and Kokwaro (1982),
numerous additional specimens of at least one other unifoliolate shrub was collected in the
Usambaras and adjoining areas, including Kenya, and erroneously attributed to V. amaniensis,
although accommodated in the expanded description of the species in FTEA. Most of this material
has the apex of the petiole winged, hairy stems, an inflorescence shorter than the petioles, and often
the odd trifoliolate leaf among the predominantly unifoliate ones. These seem to represent a further
new species that will be the subject of a future paper. None of the specimens of the putative new
species were collected in Amani. In contrast, only seven surviving specimens (see specimens
examined above) represent a species that fits the descriptions of Engler (1905) and of Verdoorn
(1926). These have thin papery, elliptic leaflets with a length: breadth ratio of c. 2.5:1, glabrous
stems, petioles which are terete at base and canaliculate at apex, inflorescences 0.9 – 4( – 5) cm
long, far exceeding (usually) the petioles, and leaves which are uniformly unifoliolate. All the
specimens are from Amani except two from nearby Bulwa. Since they match Engler’s protologue
description and location, a neotype has been selected from among them that matches the original
description, since all the original material of V. amaniensis (the syntypes Engler 565 and Warnecke
516k in Herb. Amani) have been destroyed or lost. Although Mziray (1992) states the last is at K
there is an ancient annotation to a species cover that this specimen is “not here”. In addition, the
label of Salmon G 6171 (E African Agricultural research station, Amani, 5 April 1922) states in
script contemporary with the original label, “The type is not in herb. Amani”. This suggests that no
duplicates were left by Engler’s team in the Amani Herbarium (so they could not have been
transferred to EA with the rest of that herbarium).
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Vepris ngamensis is here formally added to the synonymy of the earlier published V. amaniensis.
Treated by Mziray (1992: 78) as an “Insufficiently known taxon”, Vepris ngamensis is only known
from certainty from the type, Engler 565, also collected at Amani, but destroyed at Berlin. Although
Kokwaro also attributed Drummond & Hemsley 3349 (not found, presumed missing) to V.
ngamensis he had not actually seen the original material. When Verdoorn described Vepris
ngamensis in 1926 from material that had been annotated by Engler as Teclea ngamensis (Verdoorn
1926; Kokwaro 1982) she presumably missed the fact that this same specimen is one of the two
syntypes of V. amaniensis. Comparing the original descriptions of Vepris ngamensis (Verdoorn
1926) with that of V. amaniensis Engler (1905) shows no point of morphological difference except
in the number of stamens. The first having four (hence assigned to the genus Teclea) and the second
seven (so ascribed to Vepris). While some specimens cited above have four stamens, another
(Salamani bin Kilwa) is annotated “Stamens 5 – 6!”. Although stamen number was used to assign
species to different genera formerly, and has value as a species character, Mziray (1992) cited the
range in variation of stamens from 4 to 8 (sometimes on the same plant) in V. heterophylla as
evidence that this is not in itself a reliable character for generic separation, nor even in some cases
for separating species. We neotypify V. ngamensis above, in the absence of any original material,
choosing material from the type location that matches its protologue most closely.
11.Vepris africana (Hook.f. ex Benth.) O.Lachenaud & Onana (2021: 109). Type: S.Tomé, without
date or locality, Don s.n. (Holotype K, barcode K000199556). (Fig. 8)
Glycosmis? africana Hook.f. ex Benth. in W. J. Hooker (1849: 256).
Teclea gossweileri I. Verd. (1926: 409); Exell & Mendonça (1951: 271). Type: Angola, Cuanza
Norte, Cabiri, 1 July 1921, Gossweiler 8328 (Holotype K, barcode K000199528, K000199529)
Vepris gossweileri (I. Verd.)Mziray nom. illeg. Mziray (1992:72; Figueiredo & Smith 2008: 155;
Langat et al. 2021)
DISTRIBUTION. N. Angola (both metropolitan and Cabinda), Republic of Congo, Gabon and S.
Tomé
REPRESENTATIVE SPECIMENS EXAMINED. Republic of Congo. Bas - Kouilou, a 1.5 km
du pont Bas - Kouilou, au bord de la RN5, fr. 13 Dec. 2012, Mpandzou 1906 (IEC, K); Pointe
Noire, fr. 10 July 2011, Mpandzou 1282A (IEC, K); Tchimpounga Point 1 zone soleil 1, fr. 13 Nov.
2012, T. Kami 1327 (IEC, K, MO).
HABITAT. Coastal thicket, often on white sand (then sometimes with Vepris teva in Congo), forest
patches in wooded grassland, sometimes in rocky areas, sometimes on limestone; sea-level-1200 m
alt. (Lachenaud & Onana 2021 pro parte)
CONSERVATION STATUS. Vepris africana does not appear on iucnredlist.org. including under
its synonyms. Lachenaud & Onana (2021) give a detailed provisional conservation assessment
stating that it is Near Threatened based on 22 herbarium specimens, five of which could not be
placed geographically, resulting in 11 IUCN threat-based locations, an AOO of 48 km2, an EOO of
369,480 km2. Threats observed by Lachenaud in Gabon and S. Tomé are habitat loss and
degradation from charcoal production, urbanisation, and agriculture. The first author has observed
these same threats, and additionally port construction facing the species in the Republic of Congo,
where already locations have been lost, and others are set to follow. Given this data the authors opt
to assess the species as Vulnerable VU D2 since they agree with Lachenaud & Onana (2021) that
further of the known locations are likely to disappear in the near future.
PHENOLOGY. Flowers (June-) Sept.-Jan.; fruit Nov. and Feb.
ETYMOLOGY. Named for Africa by J. Hooker.
24
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Fig 8. Vepris africana Habitat of fruiting plant (Mpandzou 1282A, IEC, K) in white sand coastal
thicket near Pointe Noire, Republic of Congo in 2012. Photo by M. Cheek.
VERNACULAR NAMES & USES. None are known.
NOTES. Lachenaud & Onana (2021) resolved the nomenclature of this taxon and give an excellent
and detailed description, ecological and other notes and original line drawing of this species which
we have drawn upon here, supplemented by the first author of this paper’s original observations of
the species in Republic of Congo and of live plants observed in cultivation. Plants grow relatively
easily and vigorously from seed but even after 10 years had not flowered (Langat et al. 2021 under
the synonym Vepris gossweileri). Laboratory investigation has shown multi-layered anti-bacterial
synergism in combinations of minor compounds with E-caryophyllene in this species (Langat et al.
2021). In the Republic of Congo the species is only known from a distinctive coastal thicket on
white sand where it can grow with Vepris teva (Gosline et al. 2014; Cheek et al. 2014; Langat et al.
in press). Lachenaud & Onana (2021) report that Vepris africana is unusual for the genus in being
androdioecious, pollen is produced in both flower types but male flowers have pistillodes only. This
feature separates it from the similar but dioecious Comorian V. unifoliolata (Baill.) Labat, M. Pignal
& O. Pascal They attribute the presence of the species on S.Tome a volcanic oceanic island, as
probably resulting from dispersal by frugivorous birds or possibly by marine currents. The
specimens cited above are additional to those reported in Lachenaud & Onana (2021) but do not
increase the range of the species.
Vepris africana has been confused with V. welwitschii in Angola where they both occur, and both
species are superficially very similar. However, the first has subsessile flowers (pedicels 0 – 0.5 mm
long), unilocular ovaries and 4 stamens, orange fruits, the second pedicels 1 – 2.5 mm long, is
bilocular, has 8 stamens, and black fruits.
12. V. hanangensis var. unifoliolata Kokwaro (1978: 791). Type: Kenya, Nairobi, Karura Forest, fr.
23 Jan. 1970, Perdue & Kibuwa 10241 (holotype EA barcode EA000003105!; isotypes BR barcode
BR0000006273699!, K barcode K000199486!, PRE barcode PRE0594695-0!)
25
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DISTRIBUTION. Kenya, only known from Karura Forest of Nairobi
REPRESENTATIVE SPECIMENS EXAMINED. Kenya, outskirts of Nairobi, Karura Forest, 25
Oct. 1976, Kokwaro 4038 (EA, K).
HABITAT. Upland dry evergreen forest; c. 1700 m alt.
CONSERVATION STATUS. Vepris hanangensis var. unifoliolata is listed as Vulnerable (World
Conservation Monitoring Centre 1998b) under criterion D2, listing urbanisation and land clearance
for agriculture as among the key threats. In the last 20 years, Nairobi has expanded greatly,
reducing and degrading habitat. However, due to a successful campaign led by Wangari Maathai to
reject all allocations of land in Karura, and subsequent fencing by the local residents association,
the habitat of this highly range-restricted taxon is protected and an assessment of Vulnerable VU D2
seems appropriate. It is advisable that there is a baseline survey to verify that the taxon survives,
and against which monitoring and a management plan for the tree can be devised
PHENOLOGY. Fruits are known in January.
ETYMOLOGY. Named for the unifoliolate leaves of the mature trees that distinguish this taxon
from the typical variety of the species which is trifoliolate.
VERNACULAR NAMES. None are known.
NOTES. Young plants of this variety frequently have some 3—foliolate, some 2-foliolate and a
majority of 1-foliolate leaves. Unifoliolate leaves from young plants are exceptionally large, up to
30 x 12 cm (Kokwaro 1978: 791).
Vepris hanangensis var. unifoliolata in leaf might be confused with V. simplex which also occurs at
this altitude. However, Vepris hanangensis var. unifoliolata as in the typical variety, has long
cylindrical fruits held in large persistent panicles, unlike the globose fruits on reduced racemes of
the other species.
The collectors of the type stated that the tree grew up to 150 feet (=45 m) tall. This would make it
by the far the tallest growing of the African unifoliolate Vepris species. However, this is an error
since the tallest tree in Karura Forest is no more than 15 m tall (QL pers. obs. 2022). Only the two
specimens cited are known to us.
13. Vepris simplex Cheek. nom. nov. (Fig. 9).
Type: Tanzania, “Hochwaldes” (interpreted as Usambara Mts), “1300-1600” m, Sept. 1892, Holst
3801 (holotype B, probably destroyed; isotype EA barcode EA000003191!; epitype designated here
(see note below) Tanzania, Tanga Province, Lushoto Distr., Manola, 6,600 ft, fl. 16 June 1953,
Parry 222 (K barcode K000593353!)).
Vepris simplicifolia (Engl.) Mziray (Mziray 1992: 75;, White et al. 2001: 515) nom. illegit.( non
Vepris simplicifolia Endl. (Endlicher 1833: 89)
Teclea simplicifolia (Engl.) I. Verd. (1926: 410; Kokwaro 1982: 25; Gilbert 1989: 427; Friis 1992:
183; Beentje 1994: 369).
Teclea viridis I. Verd. (1926: 410). Typ: Kenya, Nairobi Forests, 5500 ft, fl. Feb. 1914, Battiscombe
867 (Holotype K 000199480!; isotype EA)
Teclea unifolioliata sensu Engl. non Baillon (Engler 1895: 433; 1897: 152)
DISTRIBUTION. Vepris simplex occurs from the Ethiopian Highlands in the vicinity of Addis
Abeba southwards along the E African rift mountains through the highlands of Kenya, and Tanzania
(Kokwaro 1982, Friis 1992, Beentje 1994), reaching the Mafinga Mts of northern Malawi (White et
al. 2001: 515). A putative record from N. Mozambique has not been confirmed by us.
REPRESENTATIVE SPECIMENS EXAMINED. ETHIOPIA. Mega Mountain, 6300 ft, fr. 9
Sept.,1953, Bally 9189 (EA, K!); Sidamo, Mogada, fl. May 1976, Chaffey 997 (ETH, K!). KENYA.
Marsabit, Mt Kulal, 1800 m, fl. Feb. 1959, T. Adamson K15(EA, K!); ibid. fr. 29 July 2006,
Nyamongo in GBK 22 (EA, K!); Kiambu Distr., Nairobi-Nakuru Rd nr Rironi shopping centre, fr 1
26
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Fig. 9. Vepris simplex Inflorescence with male flowers taken April 2018 on Philip Leakey's farm in
the Loita Hills. Photo W.R.Q. Luke.
Jan. 1976, Msafiri 22 (EA, K!); TANZANIA. Kilimanjaro, 1800 m, fl. 25 June 1993, Grimshaw
93341 (EA, K!); Arusha Distr., Ngongongare forest, fr. 5 May 1960, Willan 55 (EA, K!);
HABITAT. Dry mainly evergreen forest, riverine thicket, evergreen rocky bushland, drier types of
upland forest and woodland with Juniperus and Acacia, extending into the understorey
of Podocarpus forest (Friis 1992), and in Malawi in montane thicket (White et al. 2001). “Common
understorey tree at most levels; here in scrub/disturbed relict forest” (Grimshaw 94409, K!); 300 –
2300 m altitude.
Vepris simplex is by far the most collected species of unifoliolate Vepris in tropical Africa, with 317
specimen records on gbif.org. The majority of the specimens were collected in the 1400 – 2300 m
altitudinal band in Kenya, extending to the Ethiopian Highlands, and southwards into the high
mountains of northern Tanzania: e.g. Kilimanjaro, Mt Hanang, Mt Meru and is morphologically
uniform through much of this range, although flowers in Ethiopia are smaller than those in Kenya.
In the Arusha area, the leaves are much longer than the norm, oblong and the length: breadth ratio
about 3: 1, leaves measuring c. 14.5 x 4.5 cm e.g. Willan 514 (K!). In the main part of its range the
species often occurs on volcanic rocks such as lava flows and in at least some locations it is
“exceedingly common” (Mt Kulal, Kenya, Bally 5582, K). Further investigation is needed from
specimens from lower altitude evergreen forest areas around Morogoro, Tanzania, and in SE Kenya,
e.g. Magogo & Glover 693 (Mrima Hill, K!), Brenan et al. 14519 (Shaitani Forest near Diani, K!)
which are discordant from specimens in the rest of the range. They have large acuminate, papery
leaves, exceeding 2:1, with minute, green flowers. These might represent a separate variety or
subspecies.
27
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Hermaphrodite flowers with functional ovaries and only two stamens were observed on the
otherwise male Bally 2578 (K!), by John Hutchinson (specimen annotation).
Trees are predated by elephants (Grimshaw 93341, 94409 both K!) which favour this species, and
birds eat the fruits (Grimshaw 93341, K!), presumably dispersing the seed. This species has the
smallest fruits (3 – 5 mm diam.), borne in the greatest numbers per stem than any other unifoliolate
Vepris species, which may be an adaptation to bird dispersal and contribute to it having the greatest
range and being the most frequent of any of the species.
White et al. (2001: 516) classify the species as a Sub-Afromontane endemic while Friis (1992)
suggests it is an Afromontane endemic (Timberlake 2021c).
Vepris simplex is confused with V. eugeniifolia. See diagnostic characters under the last species.
CONSERVATION STATUS. Vepris simplex is listed as Least Concern in view of its vast range
and numerous locations, and few specific threats. It is in numerous protected areas in Kenya and
Tanzania (Timberlake 2021c).
PHENOLOGY. Flowering May-July, fruiting Sept.-Nov. (Ethiopia); flowering June-Feb., fruiting
June-Jan. (Kenya), and flowering Nov.-June, fruiting Feb.-June, Aug. (Tanzania).
ETYMOLOGY. Originally named simplicifolia by Engler for the unifoliolate (simple not
compound) leaves, now known not to be a diagnostic specific character as it must have seemed
when first published. Simplex, the new name, coined here, is intended as a convenient, shorter
alternative name which is needed since simplicifolia is not available for this species (see Notes,
below).
VERNACULAR NAMES & USES. Haddessa ormicha (Gallinia, Ethiopia, Chaffey 997 (ETH,
K!); Mwenderendu (Kikuyu), used for walking sticks (Kenya, Msafiri 22 K!); Used for charcoal
(Kenya, Mwangangi 2344, K!); Goriot (Kips.) and Ol’Gelai (Masai), for walking sticks and bows
(Kenya, Narok, Glover et al. 22, K!); Kuriot (Kips.) and Olkisi (Masai) for bows, sap for chest
troubles (Kenya, Narok, Glover et al. 2073, K!); Mulati (Kirangi), used for fuel and building poles
(Tanzania, Kondoa Distr., Ruffo 781 K!); Engelai (Masai) (Tanzania, Carmichael 387, K !); Ndireto
(Kimeru) (Tanzania, Willan 236, K !); (Ligua) (Tanzania, Semsei in FH 2946, K!); Mkuku
(Bagamoyo, Tanzania, fide Engler 1895). In addition, the names Muchimi wa Tsakani (Digo),
Muretu (Meru), Kurionde(Tugen), Edapalakuyen (Turkana), and the use of wood for roof beams
and other artefacts is reported (Beentje 1994).
NOTES. The only surviving original material of Engler (1895) located, is the isotype at EA. It is
sterile, although the protologue is based on flowering material. Therefore, an epitype is needed to
buttress the application of the name to the species and remove ambiguity. There seems some
uncertainty about the locality. On the EA isotype label an undecipherable word followed by
“Hochwald” (high forest) is written. The location has been inferred or interpreted at a later date by a
note in pencil on the label as “Usambara Mts”. However, in the protologue “Usambara Mts” are not
mentioned, although an altitudinal range of 1300 – 1600 m is given. The only place name given on
the label is Bagamoyo which was the capital of what was then German East Africa and is a historic
coastal port town near to the Usambaras. Polhill and Polhill (2015: 199) give an itinerary for Holst
in 1892, the year that he collected the original specimen. He was entirely in FTEA T3 (the botanical
province containing the Usambara Mts). Given these facts, an epitype has been selected of a fertile
specimen representative of the species, also from the T3 area, this is Parry 222 (EA, K), chosen
because it is of good quality, is in flower showing the representative large male flowers with four
stamens, and with the thick, ovate-elliptic leaflets with rounded apices that together unambiguously
indicate this species.
When Mziray (1992) made the combination Vepris simplicifolia, he was probably unaware that the
name was already occupied by Vepris simplicifolia Endl. (Endlicher 1833), which is contrary to the
Code (Turland et al. 2018). The last name was coined for a plant from Norfolk Island in the
western Pacific. It is the basionym for Sarcomelicope simplicifolia (Endl.) T.G. Hartley (1982: 369)
of Australia and New Caledonia which has many local names and likely uses (Hartley 1982).
28
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Therefore, a new name is needed for the African taxon, which is addressed above. The name Vepris
simplex was selected since it has the advantage of being similar to the name used for the last nearly
100 years, but sufficiently different to be allowed under the Code. It is also less cumbersome, being
shorter, always an advantage for users.
Mziray (1992) making the combination Vepris simplicifolia, incorrectly gave the authorship as
(I.Verd.)Mziray, mistakenly attributing authorship of the basionym to Verdoorn, when she had made
it clear that she was making a combination based on Engler’s (1895) Toddalia simplicifolia
(Verdoorn 1926). Therefore the correct authorship of her name isr Teclea simplicifolia (Engl.) I.
Verd. and that of Mziray’s is Vepris simplicifolia (Engl.) Mziray.
A note on the Eastern Arc Mountains and Coastal Forests of East Africa
The three new species published in this paper are restricted to the Eastern Arc Mountains and
Coastal Forests (EACF) of East Africa, in Tanzania and southern Kenya. The EACF form an
archipelago-like phytogeographical unit well-known for high levels of species endemism in many
groups of organisms (Gereau et al. 2016). Among the better-known mountain blocks are the Nguru
Mts, the Udzungwa Mts, the Uluguru Mts, and the Usambara Mts. Supported by moist air currents
from the Indian Ocean, the surviving evergreen forests of the Eastern Arc Mountains alone have
223 species of endemic tree (Lovett, 1998), and are variously stated to have 800 (Tanzanian Forest
Conservation Group, undated) or as many as 1500 species (Skarbek 2008) of endemic plant species.
In herbaceous groups such as the Gesneriaceae, over 50% of the taxa (23 endemic species and a
further nine endemic taxa) for East Africa (Uganda, Kenya and Tanzania) are endemic to the
Eastern Arc Mts (Darbyshire 2006) and in the Acanthaceae, there are numerous endemic species in
multiple genera endemic to the Eastern Arc Mts, e.g. Stenandrium warneckei, Isoglossa
bondwaensis, Isoglossa asystasioides and Sclerochiton uluguruensis (Vollesen 2008; Darbyshire
2009; Darbyshire et al. 2010; Darbyshire & Kelbessa 2007). In terms of documented plant species
diversity per degree square, the Eastern Arc Mts are second only in tropical Africa to Southwest
Cameroon in the Cross-Sanaga Interval of West-Central Africa (Barthlott et al. 1996; Cheek et al.
2001). Several forest genera have disjunct distributions, being found only in the Cross-Sanaga
Interval and in the EACF and not in between, e.g. Zenkerella Taub. and Kupea Cheek (Cheek et al.
2003; Cheek 2004c). The EACF include the sole representatives of plant groups otherwise restricted
on the continent to the forests of Guineo-Congolian Africa, e.g. Afrothismia Schltr. and
Ancistrocladus Wall. (Cheek & Jannerup 2006; Cheek et al. 2000). Extensive forest clearance
within the last 100–150 years has removed forest from some mountains entirely, and reduced forest
extent greatly in others. Since the 1970s more than 12% of these forests have been cleared
(Tanzania Forest Conservation Group, undated). However, forest clearance has appeared to stabilize
in the last ten years (Tanzania Forest Conservation Group, undated) in many but not all areas
important for plant conservation giving hope that species extinctions can be avoided, or at least kept
to a minimum
Conclusions
The published and provisional extinction risk assessments of the 13 unifoliolate continental Vepris
species treated in this synopsis indicate that all but two are threatened. Thankfully, the three new
species to science published in this paper are all at the lower level of extinction risk, Vulnerable, as
a result of the higher levels of protection in the Udzungwa Mountains National Park of Tanzania
(Vepris lukei and V. udzungwa), and the local community protection of the indigenous people of SE
Kenya of their Kaya forests (Vepris roberstsoniae). However, the future for the three species
indicated as Critically Endangered seems fragile or even non-existent. The forest habitat of Vepris
laurifolia in western Africa (Guinea to Ivory Coast) is steadily being reduced by development
projects of multiple sorts including mining and hydropower, and by clearance of the last scraps for
agriculture. The two species restricted to the Uluguru mountain forests are of highest concern
29
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because since they were last seen nearly 100 years ago, each from a single plant (so far as we are
aware) their forest habitat has seen massive clearance. According to Ndang’ang’a et al. (2007), the
Ulugurus had the highest losses of forest of all Tanzanian EACF areas 1970s-2000 with about 12%
loss. All forest is considered to have been lost below 1800 m alt. (East African Plant Red List
Authority pers. comm. to first author). It may be that both species are already extinct, in the case of
Vepris sp. A of FTEA (only recorded below 1800 m alt.), even before it has a scientific name or a
formal IUCN conservation assessment published. Until species are scientifically named, it is
difficult for an IUCN conservation assessment to be published (Cheek et al. 2020b, although there
are exceptions, as in Vepris robertsoniae of this paper). Most new species to science published
today, such as those in this paper, are range-restricted, meaning that they are almost always
automatically threatened, although there are exceptions, such as the widespread Vepris occidentalis
Cheek & Onana (Cheek et al. 2019a). Documented extinctions of plant species are increasing
(Humphreys et al. 2019) and recent estimates suggest that as many as two fifths of the world’s plant
species are now threatened with extinction (Nic Lughadha et al. 2020). Global extinctions of
African plant species continue apace. At the foot of the Udzungwa Mts, the achlorophyllous
mycotrophs Kihansia lovettii Cheek and Kupea jonii Cheek (Triuridaceae, Cheek 2004c) are likely
extinct as a result of the placement of the Kihansi hydroelectric dam, not having been seen since
construction in 1994 (28 years ago), despite targeted searches. Although not directly threatened by
development, another mycotroph, this time in one of the forest fragments of SE Kenya, Afrothismia
baerae (Thismiaceae, Cheek 2004b) has also not been found despite monitoring in the last 10 years.
Global extinctions have also been reported in Guinea, such as Inversodicraea pygmaea G.Taylor,
and in 2022 after first collection in 2018, Saxicolella deniseae Cheek (both Podostemaceae, both
extinct due to hydropower construction, Couch et al. 2019, Cheek et al. 2017; Cheek et al. 2022c).
New extinctions have recently been reliably reported from Gabon (Moxon-Holt & Cheek 2021,
Cheek et al 2021) and Cameroon (Cheek & Williams 1999, Cheek et al. 2018c, Cheek et al. 2019),
including species of Vepris (Cheek et al. 2018a). If future extinctions are to be avoided, improved
conservation prioritisation exercises are needed such as Important Plant Area programmes
(Darbyshire et al. 2017), supported by greater completion of Red Listing, although this can be slow
and problematic (Bachman et al. 2019). and, globally, only 21 – 26 % of plant species have
conservation assessments (Bachman et al. 2018). Where possible, as an insurance policy, seed
banking and cultivation of threatened species in dedicated nurseries are urgent. Above all,
completion of botanical taxonomic inventories is needed to feed into these exercises, otherwise we
will continue to lose species before they are even discovered for science, and certainly before they
can be investigated for their potential for beneficial applications. New compounds to science with
high potential for humanity are being discovered in Vepris species each year (e.g. potent
antimicrobial compounds in Vepris africana, Langat et al. 2021). Such discoveries will not be
possible if species extinctions are allowed to continue.
Acknowledgements
QL would like to thank Tom Butynski and Carolyn Ehardt for allowing him to accompany their
primate expeditions in the UMNP funded by Zoo Atlanta and the Margot Marsh Biodiversity Fund
We thank Nina Davies for facilitating the loans and working spaces needed for this paper in the
Kew Herbarium. Poppy Lawrence assisted in the early stages of this project. Janis Shillito typed the
manuscript.
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