1. Family: Santalaceae R.Br.
    1. Genus: Thesium L.
      1. Thesium megalocarpum A.W.Hill

        This species is accepted, and its native range is S. Tropical & S. Africa.

    [FZ]

    Flora Zambesiaca. Vol. 9, Part 3. Polygonaceae-Myriaceae. Pope GV, Polhill RM, Martins ES. 2006.

    Type
    Lectotype, chosen here: Namibia, Waterberg Plateau, Dinter 585 (K, lectotype).
    Flowers
    Flowers 1–4(6) racemosely arranged at the tips of closely leafy twiglets Flowers 1–4(6) racemosely arranged at the tips of closely leafy twiglets.
    Bracts
    Bracts 3.5–16 × 0.6–1 mm, leaf-like, adnate to very short pedicel; bracteoles 2, 2.5–7 × 0.4–1 mm Bracts 3.5–16 × 0.6–1 mm, leaf-like, adnate to very short pedicel; bracteoles 2, 2.5–7 × 0.4–1 mm.
    Pedicel
    Pedicels 0–1 mm long Pedicels 0–1 mm long.
    Perianth
    Perianth possibly greenish; tube 0.8–1.4 mm long, external glands elliptic, rather obscure; lobes 1.2–1.5 × 0.6–1 mm, triangular, subacute, white-bearded from apex Perianth possibly greenish; tube 0.8–1.4 mm long, external glands elliptic, rather obscure; lobes 1.2–1.5 × 0.6–1 mm, triangular, subacute, white-bearded from apex.
    Style
    Style 0.7–1.4 mm long; stigma reaching top of perianth tube; placenta twisted
    Ecology
    Shallow sand on rocky quartzite ridges or deep Kalahari Sand in woodland or scrubby grassland; palatable to cattle; 900–1300 m.
    Note
    The young stems, leaves and bracts of T. megalocarpum are sometimes remarkably papillose (e.g. Wild & Drummond 6902, cited above), but are commonly glabrous or show varying degrees of development of papillae or scabrid projections. Despite this variation, the species is easily recognized by its woody, twiggy habit, flowers on very short pedicels and often solitary at the tips of short closely leafy twigs (but up to 4(6) can develop), perianth lobes bearded from the apex, and remarkably large fruits with a prominent stipe. The plant is glaucous or pale green in life and may retain its colour when dry. Roessler (loc. cit.) reduced T. dinteri A.W. Hill to synonymy under T. megalocarpum, but it is a distinct species differing from T. megalocarpum, inter alia, in its flowers on pedicels c. 3–12 mm long, shorter style (c. 0.5 mm) and straight (not twisted) placenta. N.E. Brown (in Burtt Davy, Fl. Pl. Ferns Transvaal, part 2: 461 1932) effectively lectotypified the name T. dinteri by Dinter 641, from Okaruse Kalk in Namibia. There are two sheets of this collection in Zürich (Z). The other syntype, Dinter 784, has not been traced by me; it was possibly a unicate destroyed in the Berlin fire. N.E. Brown (loc. cit.) said that his new species, T. dumale was very close to Dinter 784; T. dumale has here been reduced to T. resedoides. Dinter 5440, cited by Roessler (loc. cit.) as T. megalocarpum, is T. resedoides, which should be added to the tally of species in Namibia.
    Distribution
    Zimbabwe Also in Angola, Namibia and South Africa (Northern Cape and North-West Provinces). BOT N, ZIM W, ZIM C, ZIM SE, ZAM S Botswana
    Habit
    Perennial herb or shrub, basal parts not seen, but stems probably tufted from a woody caudex; stems 250 mm–1 m long, up to 5–8 mm in diameter, profusely branched from the base, young parts weakly ribbed by decurrent leaves, glabrous to minutely papillose, leafy. Perennial herb or shrub, basal parts not seen, but stems probably tufted from a woody caudex; stems 250 mm–1 m long, up to 5–8 mm in diameter, profusely branched from the base, young parts weakly ribbed by decurrent leaves, glabrous to minutely papillose, leafy
    Leaves
    Leaves ascending, main ones c. 7–35 × 0.8–1.2 mm, sometimes smaller on the flowering twiglets, passing imperceptibly into bracts, linear to acicular, elliptic to round in section, apiculate, glabrous to minutely papillose all over. Leaves ascending, main ones c. 7–35 × 0.8–1.2 mm, sometimes smaller on the flowering twiglets, passing imperceptibly into bracts, linear to acicular, elliptic to round in section, apiculate, glabrous to minutely papillose all over
    Stamens
    Stamens inserted at base of perianth lobes; filaments 0.3–0.5 mm long, almost or quite hidden by anthers; anthers 0.5–0.7 mm long. Stamens inserted at base of perianth lobes; filaments 0.3–0.5 mm long, almost or quite hidden by anthers; anthers 0.5–0.7 mm long
    Pistil
    Style 0.7–1.4 mm long; stigma reaching top of perianth tube; placenta twisted.
    Fruits
    Fruit 3–4 × 3–4 mm, light brown, strongly ribbed and reticulate, stipe 1–3 mm long, pale. Fruit 3–4 × 3–4 mm, light brown, strongly ribbed and reticulate, stipe 1–3 mm long, pale.

    Images

    Distribution

    Native to:

    Angola, Botswana, Cape Provinces, Namibia, Northern Provinces, Zambia, Zimbabwe

    Thesium megalocarpum A.W.Hill appears in other Kew resources:

    Date Reference Identified As Barcode Type Status
    Jan 1, 1989 Dinter, K. [585], South Africa K000431789 lectotype
    Dinter, K. [912], South Africa K000431790
    Burchell, W.J. [2504], South Africa Thesium burchellii K000431630 Unknown type material
    Dinter [641], South Africa Thesium dinteri K000431775 Unknown type material

    First published in Bull. Misc. Inform. Kew 1910: 341 (1910)

    Accepted by

    • Figueiredo, E. & Smith, G.F. (2008). Plants of Angola Strelitzia 22: 1-279. National Botanical Institute, Pretoria.
    • Pope, G.V., Polhill, R.M. & Martins, E.S. (eds.) (2006). Flora Zambesiaca 9(3): 1-277. Royal Botanic Gardens, Kew.
    • Germishuizen, G. & Meyer, N.L. (eds.) (2003). Plants of Southern Africa an annotated checklist Strelitzia 14: 1-1231. National Botanical Institute, Pretoria.

    Literature

    Flora Zambesiaca
    • Merxmüller, Prodr. Fl. SW. Afrika, fam. 21: 4 (1969) pro parte. TAB. 48, fig. C.
    • F.T.A. 6, 1: 415 (1911).
    • Bull. Misc. Inform., Kew 1910: 341 (1910).
    Kew Backbone Distributions
    • Figueiredo, E. & Smith, G.F. (2008). Plants of Angola Strelitzia 22: 1-279. National Botanical Institute, Pretoria.
    • Pope, G.V., Polhill, R.M. & Martins, E.S. (eds.) (2006). Flora Zambesiaca 9(3): 1-277. Royal Botanic Gardens, Kew.

    Sources

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

    Herbarium Catalogue Specimens
    'The Herbarium Catalogue, Royal Botanic Gardens, Kew. Published on the Internet http://www.kew.org/herbcat [accessed on Day Month Year]'. Please enter the date on which you consulted the system.
    Digital Image © Board of Trustees, RBG Kew http://creativecommons.org/licenses/by/3.0/

    Kew Backbone Distributions
    The International Plant Names Index and World Checklist of Selected Plant Families 2019. Published on the Internet at http://www.ipni.org and http://apps.kew.org/wcsp/
    © Copyright 2017 World Checklist of Selected Plant Families. http://creativecommons.org/licenses/by/3.0

    Kew Names and Taxonomic Backbone
    The International Plant Names Index and World Checklist of Selected Plant Families 2019. Published on the Internet at http://www.ipni.org and http://apps.kew.org/wcsp/
    © Copyright 2017 International Plant Names Index and World Checklist of Selected Plant Families. http://creativecommons.org/licenses/by/3.0