1. Family: Achariaceae Harms
    1. Genus: Caloncoba Gilg
      1. Caloncoba welwitschii (Oliv.) Gilg

        One of the first scientific collections of Caloncoba welwitschii was made by the Austrian collector Friedrich Welwitsch, in Angola in 1855. The specific epithet welwitschii was given to this species in his honour. A pressed and dried specimen of C. welwitschii, collected by Welwitsch, is held in Kew’s Herbarium.

    [FTEA]

    Flacourtiaceae, H. Sleumer (Rijksherbarium, Leiden). Flora of Tropical East Africa. 1975

    Habit
    Shrub or generally tree, 4–14(–20) m. tall; bark greyish-brownish.
    Leaves
    Leaves ± deciduous, aggregated towards the ends of the branches; blade ovate, apex acuminate, base broadly cuneate to cordate, membranous to chartaceous, glabrous, 10–28 cm. long, (5.5–)8–20 cm. broad, 5-nerved from the base, upper lateral nerves 2–4 pairs, veins ± transverse, prominent beneath with ± pronounced reticulation of the veinlets; petiole 4–12(–19) cm. long; stipules subulate-aristate, up to 2.5 cm. long, caducous.
    Flowers
    Flowers 2–5 in a fascicle from defoliate axils, or from old branches, even from the trunk, appearing with the young leaves, up to 10 cm. in diameter; pedicels sparingly glandular, 1.5–2.5 cm. long at anthesis, up to 4 cm. in fruit.
    Calyx
    Sepals oblong-elliptic, glandular dorsally, subpersistent, 1.2–2 cm. long, 0.7–1.3 cm. broad.
    Corolla
    Petals ± 10, about twice the size of the sepals, spathulate-oblong, strongly veined towards the base, (1.6–)2.5–4.5 cm. long, (0.6–)1–2.3 cm. broad.
    Stamens
    Filaments up to 2.5 cm. long; anthers 3–4 mm. long.
    Pistil
    Ovary tuberculate; style slender, ± 1 cm. long, with 5–6 short stigmatic branches.
    Fruits
    Capsule elliptic to subglobular, 7–10(–15) cm. long, 4–6(–12) cm. across including the spines (these (1.5–)2–5 cm. long), splitting into 5–6 valves, which recurve when ripe; pericarp ± 5 mm. thick.
    Seeds
    Seeds numerous, globose, puberulous, 5–7 mm. long, 3–4 mm. broad.
    Figures
    Fig. 8/8, 9.
    [FWTA]

    Flacourtiaceae, Hutchinson and Dalziel. Flora of West Tropical Africa 1:1. 1954

    Habit
    Forest shrub or tree, to 30 ft. high
    Flowers
    Flowers white.
    [FZ]

    Flacourtiaceae, H. Wild. Flora Zambesiaca 1:1. 1960

    Habit
    Small or medium sized tree up to c. 14 m. tall, branches glabrous or puberulous.
    Leaves
    Leaves collected towards the ends of the branches; lamina up to 25 x 18 cm., membranous, ovate, apex acuminate, base rounded or slightly cordate, 5-nerved from the base; petiole up to 15 cm. long; stipules up to 2.5 cm. long, subulate-aristate, caducous.
    Flowers
    Flowers up to 10 cm. in diam., scented, borne on the previous year’s branches or on older wood, appearing with the young leaves, in fascicles of 2–5; pedicels up to c. 2–5 cm. long, sparingly glandular.
    Calyx
    Sepals 2 x 1.3 cm., imbricate, very concave, glandular on exposed parts outside, oblong.
    Corolla
    Petals white, c. 10, about twice the size of the sepals, spathulate-oblong, tapering to a short basal claw, strongly veined towards the base.
    Stamens
    Stamens very numerous with slender filaments up to 2 cm. long; anthers linear, 4 mm. long, dehiscing by apical slits.
    Pistil
    Ovary tuberculate; placentas 5–6; style slender, c. 1 cm. long, stigma-lobes 5–6, linear, obtuse or capitate.
    Fruits
    Fruit a densely echinate capsule c. 8 cm. in diam. (including spines), with slender spines 1.5–2 cm. long, splitting into 5–6 recurved valves when ripe; style persistent.
    Seeds
    Seeds numerous, 6–7 mm. in diam., globose, puberulous.
    [KSP]

    Kew Species Profiles

    General Description
    In the dense, green, tropical forest undergrowth in Africa, the profusion of petals of the bright white flowers of Caloncoba welwitschii provide quite a spectacle.

    One of the first scientific collections of Caloncoba welwitschii was made by the Austrian collector Friedrich Welwitsch, in Angola in 1855. The specific epithet welwitschii was given to this species in his honour. A pressed and dried specimen of C. welwitschii, collected by Welwitsch, is held in Kew’s Herbarium.

    Species Profile

    Geography and distribution

    Caloncoba welwitschii occurs in Nigeria, Cameroon, Gabon, Democratic Republic of Congo, Congo (Congo Brazzaville), Tanzania, Malawi, and Mozambique.

    Kew expeditions to Mozambique

    Kew botanists, including Tim Harris and Jonathan Timberlake, have recently been on expeditions to Mozambique, during which specimens of Caloncoba welwitschii were collected.

    Description

    Overview: A tree up to 14 m tall, with large leaves (about 25 cm long and 18 cm wide), having a petiole (leaf stalk) up to 15 cm long.

    Leaves: The stipules (leaf-like structures) found either side of the petiole base are up to 2.5cm long and sometimes fall off soon after the leaf is fully formed.

    Flowers: The showy, scented flowers are borne on older wood and are up to 10 cm in diameter. Each flower has about 10 white, papery petals and many stamens (male parts). The stamens are held in a cluster around the centre of the flower, and are up to 2 cm long. The style (female part) is about 1 cm long.

    Fruits: The fruit is about 8 cm across, covered in slender spines, and splits into 5 or 6 sections when mature.

    Seeds: The numerous, spherical seeds are about 6 mm in diameter.

    Kew's research on this species

    Kew scientists Sue Zmarzty and Mark Chase, are working on C. welwitschii and a group of plants closely related to it, in partnership with botanists at the National Herbarium of the Netherlands (Wageningen).

    They are investigating evidence, some of it from molecular studies (comparing the DNA of various species), that although C. welwitschiibelongs to the family Achariaceae, some plants that look very similar may actually belong to a different plant family: the Salicaceae. The Salicaceae includes the willows (such as golden weeping willow) and poplars, as well as many tropical and subtropical plants.

    Uses

    Caloncoba welwitschiihas a wide range of traditional medicinal uses in Central Africa. For example, the leaves and bark are used for treating rheumatism, and are made into poultices for applying to abscesses. The leaf-sap is used to treat headaches, and the plant itself is prescribed as a means of killing body-lice. The fruit pulp is eaten in Gabon. It has been reported that the seed oil is used to treat leprosy in the Democratic Republic of Congo.

    Cultivation

    Caloncoba welwitschii is sometimes cultivated as a medicinal plant in tropical Africa.

    This species at Kew

    Both dried and alcohol-preserved specimens of Caloncoba welwitschiiare held in Kew’s Herbarium and made available to bona fide researchers by appointment. The details of some of these specimens, including images, can be seen online in Kew’s Herbarium Catalogue.

    View details and images of specimens

    The Economic Botany Collection at Kew includes specimens of Caloncoba welwitschii wood that can be examined by researchers by appointment.

    Distribution
    Cameroon, Congo-Brazzaville, Gabon, Malawi, Mozambique, Tanzania
    Ecology
    Understorey of tropical forest; also a component of secondary forest.
    Conservation
    Least Concern according to IUCN Red List criteria.
    Hazards

    The seeds are poisonous when dried and powdered.

    [KSP]
    Use
    Medicinal, fruit pulp edible.

    Images

    Distribution

    Found In:

    Angola, Cabinda, Cameroon, Central African Repu, Congo, Equatorial Guinea, Gabon, Malawi, Mozambique, Nigeria, Tanzania, Zaïre

    Introduced Into:

    Gulf of Guinea Is.

    Caloncoba welwitschii (Oliv.) Gilg appears in other Kew resources:

    Date Identified Reference Herbarium Specimen Type Status
    Jan 1, 1973 unknown K000231149
    Jan 1, 1973 Welwitsch [537], Angola K000231150 isotype
    Jan 1, 1973 Carlos, D., Tanzania K000231152 Unknown type material
    Timberlake, J. [s.n.], Mozambique K000614495
    Harris, T. [583], Mozambique K000614174
    Harris, T. [655], Mozambique K000614235
    Milne-Redhead, E. [7602A], Tanzania 15413.000

    First published in Bot. Jahrb. Syst. 40: 462 (1908)

    Accepted in:

    • [3] Govaerts, R. (1999) World Checklist of Seed Plants 3(1, 2a & 2b): 1-1532. MIM, Deurne.
    • [6] (1960) Flora Zambesiaca 1(1): 1-336. Royal Botanic Gardens, Kew.
    • [8] (1954-1958) Flora of West Tropical Africa , ed. 2, 1: 1-828

    Literature

    • [1] The Plant List (2010). Caloncoba welwitschii.
    • [2] (2006) Scripta Botanica Belgica 35: 1-438
    • [4] Burkill, H.M. (1994). The Useful Plants of West Tropical Africa, Volume 2. Royal Botanic Gardens, Kew.
    • [5] (1973) Bulletin of the British Museum (Natural History). Botany 4: 325-411
    • [7] Wild, H. (1960). Flacourtiaceae. In: Flora Zambesiaca, Volume 1, Part 1, ed. A.W. Exell & H. Wild. A.A. Balkema, Leiden.

    • [9] in Engl. Bot. Jahrb. 40: 462 (1908).

    Sources

    Flora of Tropical East Africa
    [A] http://creativecommons.org/licenses/by-nc-sa/3.0

    Flora of West Tropical Africa
    [B] http://creativecommons.org/licenses/by-nc-sa/3.0

    Flora Zambesiaca
    [C] http://creativecommons.org/licenses/by-nc-sa/3.0

    International Plant Names Index
    The International Plant Names Index (2016). Published on the Internet http://www.ipni.org
    [D] © Copyright 2016 International Plant Names Index. https://creativecommons.org/licenses/by/3.0

    Kew Species Profiles
    Kew Species Profiles
    [E] http://creativecommons.org/licenses/by-nc-sa/3.0
    [F]

    World Checklist of Selected Plant Families
    World Checklist of Selected Plant Families(2016). Published on the Internet http://apps.kew.org/wcsp/
    [G] See http://kew.org/about-kew/website-information/legal-notices/index.htm You may use data on these Terms and Conditions and on further condition that: The data is not used for commercial purposes; You may copy and retain data solely for scholarly, educational or research purposes; You may not publish our data, except for small extracts provided for illustrative purposes and duly acknowledged; You acknowledge the source of the data by the words "With the permission of the Trustees of the Royal Botanic Gardens, Kew" in a position which is reasonably prominent in view of your use of the data; Any other use of data or any other content from this website may only be made with our prior written agreement. http://creativecommons.org/licenses/by-nc-sa/3.0
    [H] © Copyright 2016 International Plant Names Index and World Checkist of Selected Plant Families. https://creativecommons.org/licenses/by/3.0