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Coccinia intermedia — a new Cucurbitaceae species
from West Africa

Norbert Holstein, Susanne S. Renner

Systematic Botany and Mycology, Menzinger Str. 67, 80638 Munich, Germany

Corresponding author: Norbert Holstein (holstein@lrz.uni-muenchen.de)

Academic editor: H. Schaefer | Received 8 September 2011 | Accepted 9 November 2011 | Published 29 November 2011

Citation: Holstein N, Renner SS (2011) Coccinia intermedia — a new Cucurbitaceae species from West Africa. PhytoKeys
7: 27-36. doi: 10.3897/phytokeys.7.2032

Abstract

Nuclear and plastid sequences from two individuals of a suspected new species of Coccinia from West
Africa were added to an available molecular phylogeny for the remaining 27 species of the genus. Phylo-
genetic analyses of these data indicate the new species’ monophyletic status and closest relatives. Based on
four fertile collections, we here describe and illustrate Coccinia intermedia Holstein. We also provide a key

to the Coccinia species of West Africa and map their distributions.

Keywords
Benin, Ivory Coast, Ghana, leaky dioecy, molecular phylogenetics, species monophyly, Togo

Introduction

The genus Coccinia Wight et Arn. so far consisted of 27 species distributed mainly
in Sub-Saharan Africa, with centers of diversity in East Africa and southern Africa
(Holstein, ongoing monograph). Only four species were known from West Africa,
including C. longicarpa Jongkind, C. keayana R. Fern., and C. barteri (Hook. f.) Keay,
which apparently evolved during Pliocene-Pleistocene climatic oscillations (Holstein
and Renner 2011). The fourth species, C. grandis (L.) Voigt, is much more widespread,
occurring not only in Africa but also in South and South East Asia, and being natu-
ralized on several Pacific islands, Australia, and in the Neotropics. During a study of

Copyright N. Holstein, S.S. Renner SS. This is an open access article distributed under the terms of the Creative Commons Attribution License,
which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.

28 Norbert Holstein & Susanne S. Renner / PhytoKeys 7: 27-36 (2011)

the evolution and biogeography of the genus (Holstein and Renner 2011), we came
across a male specimen from the northeastern Ivory Coast that in its plastid sequences
differed sufficiently from all other sequenced material for us to suspect it might rep-
resent a new species. We therefore provisionally labeled it Coccinia sp. nov. We have
since found three more specimens of the new species, all of them with fruits, and two
with flowers, and based on their morphology as well as additional nuclear and plastid
sequences, we here describe the new species C. intermedia.

Methods

We produced new sequences of the plastid 7p/20—rps12 intergenic spacer (JN653687),
trnS°~_trnG¥“ intergenic spacer (J N653686) and the nuclear LEAFY-like second in-
tron (JN653688) from the female specimen A. Akoégninou et al. 2625 (WAG0278370)
of the new species, following standard procedures (Holstein and Renner 2011). We
added the new sequences, named “C. intermedia 2”, to our published matrices and car-
ried out maximum likelihood tree searches, using the approaches described in Holstein
and Renner (2011).

Results

Phylogenetic placement

The two Coccinia intermedia accessions in the plastid tree form a clade (Fig. 1) within
the barteri clade. In the nuclear LEAFY phylogeny, C. intermedia groups with C. bar-
teri, C. heterophylla (Hook.f.) Holstein, C. keayana, C. longicarpa, C. mildbraedii Gilg,
and C. racemiflora Keraudren (Fig. 2), albeit without bootstrap support.

Morphological description

Coccinia intermedia sp. nov.
urn:lsid:ipni.org:names:77 115897-1
http://species-id.net/wiki/Coccinia_intermedia

A Coccinia longicarpa differt calycis dentibus angustis, corolla campanulata et fructu
elliptico ad oblongo. A C. keayana et C. grandis differt calycis dentibus ad corollam
adpressis vel apicem versus leviter recurvatis et lamina foliorum subtus glandibus fuscis
provisa. A C. barteri differt floribus femineis 1-3 fasciculatis non racemosis, corolla
campanulata.

Coccinia intermedia — a new Cucurbitaceae species from West Africa 29

Cucumis sativus

100 Cucumis hirsutus
Scopellaria marginata

Peponium vogelii

Diplocyclos schliebenii
100 "——————— Diplocyclos palmatus
Coccinia barteri 7
Coccinia barteri 1 }
e

Coccinia barteri 3

Coccinia barteri 6
lel Coccinia racemiflora 2

Coccinia racemifiora 1
Coccinia barteri 4
| — Coccinia barteri 2
Coccinia barteri 5

Coccinia subsessiliflora
Coccinia heterophylla
~->———- Coc cinia longicarpa
Coccinia keayana 1
93' Coccinia keayana 2

| Coccinia intermedia 2
100! Coccinia intermedia 1

-— Coccinia mildbraedii
99 ' Coccinia mildbraedii 2

Coccinia mackenii

Le 98! Coccinia quinqueloba

-— Coccinia hirtella 2

97° Coccinia hirtella 1

Coccinia sessilifolia

Coccinia senensis 5

Coccinia senensis 6
Coccinia senensis 3
Coccinia senensis 4 \ .
Coccinia senensis 2

Coccinia senensis 1
Coccinia aurantiaca 3
Coccinia aurantiaca 4
Coccinia aurantiaca 2
Coccinia aurantiaca 1
Coccinia samburuensis
—| Coccinia schliebenii 1
Coccinia schliebenii 2
[— Coccinia grandiflora 1
99' Coccinia grandiflora 2
Coccinia adoensis 2
100 80! [85'— Coccinia adoensis 5
Coccinia adoensis 8
Coccinia adoensis 3
-— Coccinia adoensis 7
86! Coccinia adoensis 4
[—— Coccinia adoensis 9
94 Coccinia adoensis 1
100' Coccinia adoensis 6
t— Coccinia grandis 3
98l— Coccinia grandis 1
"— Coccinia grandis 2
———————- Coccinia ogadensis
Coccinia abyssinica 1
85! Coccinia abyssinica 2
86] -—_ Coccinia megarrhiza 2
Coccinia megarrhiza 3
LY Coccinia megarrhiza 1
Coccinia megarrhiza 4
81 -—— Coccinia microphylla 2
Coccinia microphylla 1
Coccinia trilobata
*50 Coccinia rehmannii 1
[— Coccinia rehmannii 2 var. littoralis
Coccinia rehmannii 3 var. rehmannii
— Coccinia rehmannii 4 ,,ovifera“

Figure |. Maximum likelihood phylogeny for Coccinia based on plastid DNA sequences analyzed under
GTR+P model of substitution. The tree is based on 4,551 nucleotides (140 parsimony-informative sites)
from the trnS°°"—trnGV intergenic spacer (IS), the rp/20-rps12 IS, the ndhF—rp/32 IS, trnL** intron,
trnL©“—trnFo“ IS, and the matK gene (expanded matrix from Holstein and Renner 2011). Numbers
below branches represent bootstrap support > 80% from 1000 replicates. Dots on branches and be-
hind brackets refer to uniquely shared insertions or deletions. Species names follow Holstein and Renner
(2011) except for the new species C. intermedia 1, earlier called Coccinia sp. nov.

Type. BENIN. Atakora: Natitingou, Kouaténa (Perma), 10°12.00'N; 1°30.18'E,
river bed, female, fl, fr, 3 Oct 2000, A.Akoégninou et al. 3625 (Holotype:
WAG0278370!; isotype: WAG0278369!).

Description. Perennial, diclinous climber. Shoot length unknown, but likely
several meters. Shoots lignify with whitish bark and up to 1 cm diam. Fresh shoots
green, glabrous, older shoots with clear to white pustules. Petioles 2.8-10.8 cm,
glabrous, when older with clear to white pustules (Fig. 3a). Leaves 6-15 x 7-18
cm, shallowly to profoundly 5-lobate, more or less auriculate (Fig. 4). Upper lamina
glabrous with clear to whitish pustules. Lower lamina paler than upper lamina, gla-
brous, often with small dark glands near the leaf base (Fig. 3a). Tendrils simple or

30 Norbert Holstein & Susanne S. Renner / PhytoKeys 7: 27-36 (2011)

Peponium vogelii
Diplocyclos schliebenii
100 "——————— Diplocyclos palmatus

Coccinia hirtella 1
e -— Coccinia quinqueloba
Coccinia sessilifolia

Coccinia microphylla 2

Coccinia rehmannii 3 var. rehmannii
Coccinia rehmannii 1

Coccinia microphylla 1

94 Coccinia rehmannii 4 "ovifera"
| Coccinia megarrhiza 2
99! Coccinia megarrhiza 4
Coccinia samburuensis
e Coccinia adoensis 9
Coccinia adoensis 2
95 Coccinia aurantiaca 3

Coccinia aurantiaca 2
Coccinia senensis 1
91° Coccinia senensis 2

Coccinia mildbraedii 2
Coccinia keayana 2

Coccinia barteri 4
98 ————— Coccinia racemiflora 1
Coccinia racemiflora 2
Coccinia barteri 6
Coccinia heterophylla
Coccinia barteri 2
Coccinia longicarpa

99

Coccinia intermedia 2
Coccinia schliebenii 2

Coccinia grandiflora 2

Coccinia grandiflora 1

Coccinia grandis 1

99 | Coccinia grandis 3 © dt, hae eee

Coccinia grandis 2

Figure 2. Maximum likelihood phylogeny for Coccinia based on nuclear DNA sequences from the
LEAFY-like 2" intron analyzed under the GTR+I° model of substitution. The tree is based on 505 nucleo-
tides (56 parsimony-informative sites). Numbers below branches represent bootstrap support 2 80% from
100 replicates. Dots on branches and behind brackets refer to uniquely shared insertions or deletions.

Species names follow Holstein and Renner (2011) except for the new species C. intermedia.

bifid. Probracts up to 2.5 mm long, glabrous, apex rounded (Fig. 3a). Male flowers
in few-flowered racemes (Fig. 5), likely sometimes accompanied by a single flower.
Common peduncle up to 1 cm, pedicels in racemose flowers 2-4 mm, glabrous.
Bracts up to 1.5 mm long, round to obovoid. Receptacle pale green, glabrous. Calyx
teeth 1.5 mm long, lineal to narrow triangulate, erect with slightly recurved tips
(Figs. 3-5). Corolla campanulate, 1.6 cm long, pale reddish-yellow to yellow, lobes
0.7 cm long (Fig. 5). Anthers sinuate, in a globose head (Fig. 3c). Pollen unknown.
Female flowers 1-3 clustered (strongly reduced raceme; Fig. 4). Pedicels 0.6-1.2
cm, glabrous. Perianth like in males. Ovary fusiform, glabrous. Stigma and stami-
nodes unknown. Fruit 4.5 x 2.5 cm, elliptical to oblong, smooth. Unripe green
with pale green longitudinal mottling. Ripe orange?, more likely becoming red via
orange ripening stage. Fruit with waxy cover. Size of mature seeds unknown (2 5.5
x 3.5 x 1.3 mm), symmetrical (to slightly asymmetrical), face flat (Fig. 3b).

Distribution. (Fig. 6). NE Ivory Coast, SE Ghana (likely also in the north), S
Togo (likely also in the north), NW Benin. Based on the current collections, Coccinia
intermedia is likely to occur in the Dahomey Gap region and the /soberlinia woodlands
of West Africa.

Ecology. Wooded grasslands (semi-humid savanna), woodlands, dry forests, and
along rivers. Flowering specimens have been collected during May, August, and Octo-
ber, which in each site was during or shortly after the rainy season.

Coccinia intermedia — a new Cucurbitaceae species from West Africa 31

Figure 3. a Coccinia intermedia \eaf basis and node with flowers b seeds from late, but immature fruit

C node with young fruit and male flower bud with sinuate anthers; all from J.B.Hall & J.M.Lock GC46016 (K).

Etymology. The epithet refers to the species’ status as the only Coccinia from West
Africa that occurs in habitats intermediate between semi-arid and humid conditions.
Morphologically, C. intermedia combines characters also found in the other four West
African species although not in this combination.

List of specimens examined. Benin: Atakora, Natitingou, Kouaténa (Perma),
10°12.00'N; 1°30.18'E, river bed, female, fl, fr, 3 Oct 2000, A-Akoégninou et al. 3625
(WAG 2 sheets). Ghana: Shai Hills Game Reserve, monoecious, fl, fr, 25 May 1976,
J.B.Hall & J.M.Lock GC 46016 (K 4 sheets, MO). Ivory Coast: Bouna, male, fl,
10 Aug 1967, C.Geerling & J.Bokdam 662 (MO, WAG). Togo: between Lomé and
Aného, female, fr, 25 Jun 1994, L.Aké Assi 18982 (MO).

D2

Norbert Holstein & Susanne S. Renner / PhytoKeys 7: 27-36 (2011)

Figure 4. Habitus of Coccinia intermedia as reconstructed from J.B.Hall & J.M.Lock GC46016 (K).

Key to West African Coccinia species

1

Plant glabrous. Leaves with few large pale glands between main nerves of
lower lamina. Nerves on lower lamina with or without white pustules. Leaf
margin dentate, in mature plants often red to brown (black when dry). ‘Ten-
drils always simple. Male and female flowers 1 solitary (rarely male flowers
clustered or in short-peduncled racemes). Calyx teeth spreading to reflexed,
tips red to brown. Corolla campanulate, white or buff. Fruit ovoid. Plant of
semi-arid abitatsesccstasccusandsenScaetadithisaaeraclvetbeadderctis ea lees C. grandis
Plant glabrous or with hairs, especially on adaxial petiole. Leaves with small
blackish glands (often many) centered towards the leaf base or without glands
on lower lamina. Tendrils simple or bifid. Male and female flowers in racemes
or solitary. Corolla in yellowish tones, never White. ..........ceeeeseeseeeseeseeeeeees 2
Plant glabrous. Leaves with small blackish glands centered towards the leaf
base (Fig. 3). Nerves on lower lamina with or without white pustules. Leaf
margin at maturity with colored teeth (color in living plants unknown, black
when dry). Tendrils simple or bifid. Male flowers (Fig. 5) bracteate, in few-
flowered racemes, female flowers 1-3 solitary/clustered (Fig. 3 and 4). Calyx
teeth erect with recurved tips (Figs 3-5). Corolla campanulate. Fruit ovoid
to short cylindrical. Plant of wooded grasslands (tree savanna), woodlands, or
CLEVGEGEESUS? » cs taetatrs onset ht cn ust snricanivcewnntes ipiogtevPaeentsn sastecey tresne easter C. intermedia
Plant glabrous or with hairs, esp. on adaxial petiole. Leaves with small black-
ish glands centered towards the leaf base or without glands. Nerves on lower

Coccinia intermedia — a new Cucurbitaceae species from West Africa 33

oh staan sy? i
ye fy

Figure 5. Male inflorescence of Coccinia intermedia from C.Geerling & J.Bokdam 662 (WAG).

leaf lamina without white pustules. Tendrils simple or bifid. Male flowers in
few to many-flowered racemes, rarely accompanied by a solitary flower. Fe-
male flowers in few- to many-flowered racemes or solitary. Flowers bracteate
or ebracteate. Corolla urn-, cup- to funnel-shaped. Plant of humid climates
(rainterests toallleryforestsy Ct@l) yes scsatisnatnmsniucseenerasconur andes cate 3
3) Leaf margin with pale (when dry blackening) glandular teeth. Tendrils sim-
ple. Flowers without bracts, calyx teeth erect, > 1.5 mm at base. Fruits long

fey a FAY ad Cet) hac ce avast arnt Dec RAP ei Ser PS ers oor C. longicarpa

34 Norbert Holstein & Susanne S. Renner / PhytoKeys 7: 27-36 (2011)

S, Leaf margin without conspicuously colored teeth. Tendrils simple or bifid.
Flowers with or without bracts. Calyx teeth erect, spreading, or reflexed, but
narrow (< 1.2 mm at base). Fruits OVOiId. ..........cccccccccccesececcessssessssssecesersecees 4
4 Tendrils simple. Male flowers in lax racemes, female flowers solitary or in
few-flowered racemes. Flowers without bracts. Calyx teeth in buds spreading,
Pater TeHeKedls...cseactou.sokeseapiasncetsne oustea vast phonies See hee Sarees ste nian C. keayana
4! Tendrils simple or bifid. Male flowers in dense few- to many-flowered ra-
cemes, with or without bracts. Female flowers in racemes, rarely solitary.
Flowers with or without bracts. Calyx teeth variable. .......... eee C. barteri

Discussion

Coccinia intermedia is morphologically similar to the other West African species. From
C. grandis, it differs most readily in the glands on the lower lamina and in its calyx
teeth (erect with recurved tips in C. intermedia and spreading to reflexed in C. grandis).
From C. longicarpa, it differs in its ovoid fruits (instead of long cylindrical fruits in C.
longicarpa). Additionally, C. longicarpa has ebracteate racemes and much broader (>
1.5 mm at the base) erect calyx teeth, and an urn-shaped corolla. From C. keayana, it
differs in having bracteate male flowers in denser racemes, a campanulate corolla and
calyx teeth that are adpressed to the corolla with recurved tips, instead of spreading
(in buds) to reflexed calyx teeth. Secure distinction of C. intermedia from C. barteri
requires fertile material with flowers (see the key above).

Ecologically, the new species is a member of White's (1983) Sudanian center of
endemism and his Guinea-Congolia/Sudania regional transition zone (Fig. 6). The
only species with a similar habitat as C. intermedia is C. adoensis, the most western
known occurrence of which is Adamawa State (eastern Nigeria). Whether the species
co-occur is not known. They could be distinguished by fruit shape (not beaked in
C. intermedia, beaked in C. adoensis, although this character can vary in the latter).
Additionally, C. adoensis has inflorescence peduncles that are longer than 1 cm (in
its male racemes) and petioles that are often hairy.

Two DNA characters, namely base pairs 310 and 323 in the zrnSSC'—trnGUS
intergenic spacer region, suggest the placement of C. intermedia as sister to a clade
that we have earlier referred to as the Coccinia barteri clade (Holstein and Renner
2011). If this placement is correct, then the Coccinia species occurring in the rain or
mist forests of West and Central African are monophyletic and probably evolved in
situ. One of the four collections, J.B.Hall & J.M.Lock GC 46016, bears male and
female flowers/fruits on the same node (Fig. 3c). The male flowers are buds, and it
is not clear, whether they are fertile. Kumar and Vishveshwaraiah (1952) report a
“gynodioecious form” of C. grandis in which the male flowers of the hermaphrodite
(monoecious) plants are sterile. An occasional occurrence of bisexual plants in oth-
erwise dioecious species, sometimes called “leaky dioecy” (Baker and Cox 1984),
has also been observed in other Cucurbitaceae (Schaefer and Renner 2010).

Coccinia intermedia — a new Cucurbitaceae species from West Africa 35

Gap

Figure 6. Map of West African Coccinia species. Pale yellow circles = C. intermedia, cyan circles = C.
grandis, dark blue circles = C. barteri, pale blue squares = C. keayana, bright blue triangles = C. longicarpa.
Thick dark grey lines are phytochoria drawn after White (1983), I = Guineo-Congolian regional center of
endemism, III = Sudanian regional center of endemism, XI = Guinea-Congolia/Sudania transition zone,
XVI = Sahel regional transition zone. Thin dark grey lines (after White (1983)) differentiate between
White's vegetation types of zone IH: 27 = Sudanian woodland with abundant J/soberlinia; 29a = undif-
ferentiated Sudanian woodland. Location of C. intermedia in Ivory Coast estimated (only the department

is given on the herbarium sheet).

However, true monoecy in C. intermedia would be surprising as none of ca. 1,500
specimens of other Coccinia species studied is bisexual (Holstein, ongoing monograph).

Acknowledgements

We thank Dietrich Podlech for help with the diagnosis. We also thank the curators of
K, MO, and WAG for sending material on loan, and permission to dissect material
(K) and extract DNA (MO, WAG). The work was supported by German Research
Council (RE 603/6—1 and 6-2).

References

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Botanical Garden 71: 244-253.

Holstein N, Renner SS (2011) A dated phylogeny and collection records reveal repeated biome
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doi: 10.1186/1471-2148-11-28

36 Norbert Holstein & Susanne S. Renner / PhytoKeys 7: 27-36 (2011)

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Schaefer H, Renner SS (2010) A three-genome phylogeny of Momordica (Cucurbitaceae) sug-
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