Commicarpus pentandrus

Abstract

This is the first species of the Nyctaginaceae to be illustrated in Flowering Plants of Africa. It is commonly known as the four o’clock family, as most members have flowers that open in the late afternoon to early evening. The family is renowned for its genera Mirabilis (commonly known as four o’clocks) and Bougainvillea (commonly known as Bougainvilla) for their brightly coloured and profuse flowering. These and most other genera are mainly distributed in the Neotropics and western North America, and globally the family consists of 30 genera with 300–400 species. In southern Africa, the family is represented by five genera with 20 species. Commicarpus Standl. is the genus in southern Africa with the largest and most spectacular flowers.

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PLATE 2295 Commicarpus pentandrus
1
23

Flowering Plants of Africa 63: 98–103 (2013) 99
Tropical and southern Africa
Commicarpus pentandrus (Burch.) Heimerl in Die Natürlichen Pflanzenfamilien: 16C: 117
(1934); Boerhavia pentandra Burch.: 432 (1822); B. grandiflora sensu Oliv.: 142 (1875), non A. Rich.; B.
plumbaginea var. pentandra (Burch.) Heimerl: (1897); B. transvaalensis Gand.: 221 (1919); B. burchellii
Choisy: 455 (1949), nom. superfl. based on B. pentandra Burch.
This is the first species of the Nyctaginaceae to be illustrated in Flowering
Plants of Africa. It is commonly known as the four o’clock family, as most members
have flowers that open in the late afternoon to early evening (Levin et al. 2001).
The family is renowned for its genera Mirabilis (commonly known as four o’clocks)
and Bougainvillea (commonly known as Bougainvilla) for their brightly coloured
and profuse flowering. These and most other genera are mainly distributed in the
Neotropics and western North America, and globally the family consists of 30 genera
with 300–400 species (Douglas & Spellenberg 2010). In southern Africa, the family
is represented by five genera with 20 species. Commicarpus Standl. is the genus in
southern Africa with the largest and most spectacular flowers.
Commicarpus was originally regarded as a section of Boerhavia L. (Boerhavia sect.
Adenophorae Heimerl) (Heimerl 1889), but was segregated based on morphological
differences (Standley 1909). Boerhavia species have an upright or diffuse habit, the
inflorescence is a compound cyme and the flowers are campanulate. The anthocarps
(defined as a fruit enclosed by a persistent perianth [Hickey & King 2000]) are
clavate, fusiform or oblong with five ribs or 3–5 wings, and the surface is smooth or
covered with multicellular hairs. In contrast, Commicarpus species are subshrub-like,
spreading or scrambling herbs, the inflorescence is an umbel and the flowers are
infundibiliform. The anthocarps are cylindrical, fusiform, clavate or elliptic-clavate
with ten ribs and sessile or stalked mucilaginous glands (Stannard 1988). Molecular
studies support this segregation and indicate that Boerhavia and Commicarpus form
monophyletic groups (Douglas & Manos 2007).
The genus Commicarpus consists of about 30–35 species distributed worldwide
in the tropical and subtropical regions, mainly in Africa and western Asia (Bittrich &
Kühn 1993; Douglas & Spellenberg 2010). Northeastern tropical Africa and southern
Arabia are considered to be the centres of diversity for this genus (Thulin 1990). In
Africa, the genus is distributed throughout the continent, except for the extreme
north and south and the wet forested areas of the west (Meikle 1978). The spe-
cies have a preference for arid environments with 12 species occurring in Somalia,
Ethiopia and adjacent regions of tropical Arabia, seven species in Namibia, and five
in South Africa (Meikle 1978).
Germishuizen & Meyer (2003) list eight species of Commicarpus for south ern
Africa; of these C. pentandrus is the most common and widespread species, occurring
Commicarpus pentandrus Nyctaginaceae
PLATE 2295.—1, habit, × 1; 2, flower, × 3; 3, anthocarp, × 6. Voucher specimen: Struwig 140 in A.P.
Goossens Herbarium, Potchefstroom. Artist: Gillian Condy.

100 Flowering Plants of Africa 63 (2013)
in Namibia, Bot swana and South Africa
(Figure 1). Commicarpus pentandrus
also occurs throughout tropical Africa
(Klopper et al. 2006).
Commicarpus pentandrus was first
collected by William J. Burchell [1781–
1863] along the Vaal River in Griqua-
land West, South Africa. He described
it as Boerhavia pentandra Burch. in his
book, Travels in the interior of southern
Africa (1822), but the taxon was later
transferred to Commicarpus by Heimerl
(1934). It is a forb with trailing stems
of up to 1 m with striking bright pink
or purple flowers carried in umbels on
tall, upright peduncles. It is commonly
known as cerise stars, referring to the
flower colour, or veldpatat (Afrikaans), in reference to the rootstock, which can be up
to 30 mm thick and 300 mm long, resembling a sweet potato (Figure 2). Commicarpus
pentandrus flowers and produces fruits from October to May, but flowers and fruits
can appear as early as August (late winter) and as late as July (mid winter).
Commicarpus pentandrus is common in bare patches in grassland, savanna and
bushveld. It occurs on floodplains, plains, depressions, valleys, hill slopes or out-
crops in well-drained to moist, stony or gritty soil.
The flowers of Commicarpus species are divided into an upper petaloid part and
a lower coriaceous part. The shape and sculpturing of the lower, coriaceous part of
the flowers, as well as the shape and sculpturing of the anthocarps, differ among the
Commicarpus species of southern Africa (Struwig 2012). Commicarpus pentandrus dif-
fers from the rest of the species in that the apex of the lower part of the flower has
one or two rows of five prominent sessile glands with smaller, less prominent glands
scattered over the surface below the apex. The anthocarps have five thickly stalked
glands alternating with five smaller, less prominent glands around the apex and ses-
sile glands are scattered over the surface below the apex.
Commicarpus chinensis subsp. natalensis and C. pilosus are often confused with C.
pentandrus. The former easily, as both species are forbs with trailing stems and pink
or purple flowers in umbels on long, upright peduncles. Commicarpus pilosus is often
mistaken as C. pentandrus, as their distribution ranges overlap and both species have
purple flowers. However, these three species differ significantly in the shape and
sculpturing of the lower part of the flower and the anthocarp (Table 1).
Commicarpus chinensis subsp. natalensis and C. pentandrus are allopatric, as the for-
mer is habitat specific, occurring on coastal dunes and forest edges along the north
FIGURE 1.—Known distribution of Commicarpus pentan-
drus in the FSA region based on specimens in the
National Herbarium, Pretoria.

Flowering Plants of Africa 63 (2013) 101
coast of KwaZulu-Natal. Commicarpus
pilosus differs in habit from C. pen-
tandrus in that it is not trailing, but sub-
shrub-like and up to 1 m tall.
Plants of C. pentandrus from Sekhu-
khuneland, differ morphologically to
plants occurring elsewhere in that
the branches are shorter, the leaves
are smaller and arranged less densely.
Molecular studies are currently in pro-
gress to ascertain different phenotypes.
A root decoction of C. pentandrus
is used in Namibia and elsewhere in
Africa to treat gonorrhea (Neuwinger
2000; Von Koenen 2001) and the whole
plant is used as fodder in South Africa
(Cooke 1912; Burtt Davy 1926; Stan-
nard 1988). The plant is also used in
Tswana traditional culture for magical
purposes (Hedberg & Staugard 1989).
The generic name, Commicarpus
(Greek for Commi, meaning gum, and
carpus, meaning fruit), refers to the
sticky anthocarp (Meikle 1978). The
specific epithet, pentandrus, means
with five stamens (Glen 2007).
TABLE 1.—Shape and sculpturing of the lower part of the flower and the anthocarp of Commicarpus chinensis
subsp. natalensis, C. pentandrus and C. pilosus
Species Lower floral part Anthocarp
Shape Indumentum Shape Indumentum
C. chinensis subsp.
natalensis
Cylindrical Sessile glands scattered
over the surface
Cylindrical Sessile glands around the
apex and wart-like glands
scattered over the surface
below the apex
C. pentandrus Clavate One or two rows of five
prominent sessile glands
around the apex with
smaller, less prominent
glands scattered over the
surface below the apex
Clavate Five thickly stalked glands
alternating with five smaller,
less prominent glands around
the apex; sessile glands
scattered over the surface
below the apex
C. pilosus Elliptic Five prominent sessile
glands around apex with
smaller, less prominent
glands scattered over the
surface below the apex
Elliptic-clavate,
tapering to both
ends
Five shortly stalked glands
around the apex and sessile
glands are scattered over
surface below the apex
FIGURE 2.—Rootstock of Commicarpus pentandrus
which can be up to 30 mm thick and 300 mm
long. Photograph: S.J. Siebert.

102 Flowering Plants of Africa 63 (2013)
Commicarpus pentandrus germinates easily from seed and in cold climates is culti-
vated in a greenhouse at 25°C in a mixture of river sand, soil and compost. The addi-
tion of Multifeed® K will ensure optimum growth.
Description.—Perennial herbs, prostrate or procumbent up to 1 m long, from a
woody rootstock up to 30 mm thick and 300 mm long. Stems sometimes tinged pur-
ple; pubescent. Leaves petiolate, petiole (4–)8(–12) mm long; ovate, elliptic, orbicular,
deltoid, (13–)27(–39) × (13–)20(–29) mm, apex apiculate, rounded to acute, base
cordate, truncate, cuneate, rounded, obtuse, subcordate or shortly attenuate, upper
sides darker than undersides; margin entire; sparsely pubescent; slightly fleshy.
Inflorescence pedunculate, peduncles (30–)79(–150) mm long; umbellate, sometimes
up to three whorls of umbels and up to six flowers per umbel; pubescent; bracte-
ate. Flowers pedicellate, pedicels (2–)7(–18) mm, flowers (12–)15(–23) mm long,
bisexual. Perianth divided into a lower and upper part; lower part (2–)4(–6) mm long,
clavate, greenish, coriaceous, constricted above ovary, with ten narrow, longitudinal
grooves, one or two rows of five prominent sessile glands around the apex with
smaller, less prominent glands scattered over the surface below, persistent; upper
part (9–)11(–17) mm long, infundibuliform, petaloid, purple or pink, lobed, with a
distinct greenish, basal tube, caducous after anthesis. Stamens 4–6, long exserted,
filaments 11–17 mm long, anthers 0.7–0.8 × 1.2–1.5 mm long, transversely elliptic.
Ovary 0.75–1.00 mm long, ellipsoid, stipitate; style 14–20 mm long, long exserted.
Anthocarp (7.0–)8.4(–9.0) × (2.0–)2.1(–3.0) mm, 10-ribbed; clavate, five thickly
stalked glands alternating with five smaller, less prominent glands around the apex,
sessile glands scattered over surface below the apex; glabrous. Plate 2295.
REFERENCES
BITTRICH, V. & KÜHN, U. 1993. Nyctaginaceae. In K. Kubitzki, J.G. Rohwer & V. Bittrich, The families
and genera of vascular plants – dicotyledons 2. Springer-Verlag, Berlin.
BURCHELL, W.J. 1822. Travels in the interior of Southern Africa 1. St Martin’s Press, London.
BURTT DAVY, J.B. 1926. A manual of the flowering plants and ferns of the Transvaal with Swaziland, South
Africa. Part 1, Pteridophyta to Bombacaceae. Longmans, Green and Co., London.
CHOISY, J.D. 1849. Nyctaginaceae. In A. de Candolle, Prodromus systematis naturalis regni vegetabilis
13. Masason, Paris.
COOKE, T. 1912. Order CVII. Nyctagineae. In W.T. Thiselton-Dryer, Flora capensis 5,1: 392–398. Lovell
Reeve & Co., London.
DOUGLAS, N.A. & MANOS, P.S. 2007. Molecular phylogeny of Nyctaginaceae: taxonomy, biogeogra-
phy and characters associated with a radiation of xerophytic genera in North America. American
Journal of Botany 96,5: 856–872.
DOUGLAS, N.A. & SPELLENBERG, R. 2010. A new tribal classification of Nyctaginaceae. Taxon 59,3:
905–910.
GANDOGER, M. 1919. Boerhavia transvaalensis Gand. Bulletin de la Société Botanique de France 66,1: 221.
GERMISHUIZEN, G. & MEYER, N.L. (eds). 2003. Plants of southern Africa: an annotated checklist.
Strelitzia 14. National Botanical Institute, Pretoria.
GLEN, H. 2007. What’s in a name. Jacana, Johannesburg.
HEDBERG, I. & STAUGARD, F. 1989. Traditional medicine in Botswana. Traditional medicinal plants. Ipeleng
Publishers, Stockholm.
HEIMERL, A. 1889. Nyctaginaceae. In A. Engler (ed.), Botanische Jahrbücher für Systematik, Pflanzen-
geschichte und Pflanzengeographie 10. Von Wilhelm Engelmann, Leipzig.
HEIMERL, A. 1897. Beiträge zur Systematik der Nyctaginaceen 29. Im Selbstverlage des Verfassers, Wien.

Flowering Plants of Africa 63 (2013) 103
HEIMERL, A. 1934. Nyctaginaceae. In A. Engler & K. Prantl (eds), Die Natürlichen Pflanzenfamilien, 2 ed.
16C. Engelmann, Leipzig.
HICKEY, M. & KING, C. 2000. The Cambridge Illustrated Glossary of Botanical Terms. Cambridge University
Press, Cambridge.
KLOPPER, R.R., CHATELAIN, C., BÄNNINGER, V., HABASHI, C., STEYN, H.M., DE WET, B.C., ARNOLD,
T.H., GAUTIER, L., SMITH, G.F. & SPICHIGER, R. 2006. Checklist of the flowering plants of Sub-
Saharan Africa. An index of accepted names and synonyms. South African Botanical Diversity
Network Report No. 42: SABONET, Pretoria.
LEVIN, R.A., RAGUSO, R.A. & MCDADE, L.A. 2001. Fragrance chemistry and pollinator affinities in
Nyctaginaceae. Phytochemistry 58: 429–440.
MEIKLE, R.D. 1978. A key to Commicarpus. Notes from the Royal Botanical Garden, Edinburgh 36: 235–
249.
NEUWINGER, H.D. 2000. African traditional medicine. A dictionary of plant use and applications.
Medapharm Scientific Publishers, Germany.
OLIVER, D. 1875. Transactions of the Linnean Society of London. vol. 29. Nelson, Edinburgh.
STANDLEY, P.C. 1909. Allioniaceae of the United States with notes on Mexican species. Contributions
from the United States National Herbarium 12,8: 303–389.
STANNARD, B.L. 1988. Nyctaginaceae. In E. Launert (ed.), Flora zambesiaca, 9,1: 12–28.
STRUWIG, M. 2012. A systematic study of Boerhavia L. and Commicarpus Standl. (Nyctaginaceae) in
southern Africa. Ph.D. thesis, North-West University, Potchefstroom.
THULIN, M. 1990. Four new species of Commicarpus (Nyctaginaceae) from NE tropical Africa. Nordic
Journal of Botany 10,4: 403–409.
VON KOENEN, E. 2001. Medicinal, poisonous and edible plants in Namibia. Klaus Hess Verlag, Germany.
M. STRUWIG*§, S.J. SIEBERT* and GILLIAN CONDY**
* A.P. Goossens Herbarium, Unit for Environmental Sciences and Management, North-West
University, Private Bag X6001, Potchefstroom, 2520 South Africa.
§ Author for correspondence: madeleen.struwig@nwu.ac.za
** South African National Biodiversity Institute, Private Bag X101, Pretoria, 0001, South Africa.