1. Family: Polygonaceae Juss.
    1. Genus: Rumex L.
      1. Rumex usambarensis (Engl.) Dammer

        This species is accepted, and its native range is Congo to Kenya and N. Zambia.

    [FTEA]

    Polygonaceae, R. A. Graham. Flora of Tropical East Africa. 1958

    Habit
    A shrub or straggling glabrous climber, up to 3 m. tall or more.
    Stem
    Stems brown.
    Leaves
    Leaves astringent, petiolate, often clustered, narrowly to broadly elliptic with a hastate base, a little narrowed above the basal lobes, up to 5 (–9) cm. long, apically acute; lobes reflexed, small, not exceeding 5 × 2 mm.; leaves markedly trinervate (except in very narrow leaves), the lateral nerves arising arcuately from the base of the midrib and remaining complementarily parallel throughout most of their length.
    Petiole
    Petioles 1–4 cm. long.
    Inflorescences
    Inflorescence a much-branched, ± slender, leafless panicle.
    Flowers
    Flowers in fascicles, on filiform pedicels up to 5 mm. long.
    Tepal
    Outer tepals 1.75–2 mm. long, ovate, obtuse, later reflexing. Inner tepals wing-like, 5–7 mm. in diameter, ± pellucid, subequal, circular when mature, with a squarish basal sinus 1–1.5 mm. deep, red or reddish-brown, reticulately veined and with a small wart-like reflexed protuberance at the base.
    Fruits
    Nut trigonous, ovoid, 2–2.5 × 1 mm., brown, shining.
    Figures
    Fig. 2/1 and 2.
    Habitat
    Open mist-forest, also upland grassland, bushland and exposed rocky slopes, 870–2400 m.; occasionally cultivated for its medical properties.
    Distribution
    K3 K4 K6 T2 T3 T4 T7 U2 U3 U4
    [FZ]

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

    Habit
    A shrub, or sometimes a straggling climber A shrub, or sometimes a straggling climber.
    Stem
    Stems up to 3 m or more tall, glabrous, striate Stems up to 3 m or more tall, glabrous, striate.
    Leaves
    Leaf lamina 3.5–9 × 1.5–3 cm, narrowly to broadly elliptic, apex acute, with a hastate base, narrowed above the basal lobes, markedly 3-nerved; basal lobes 5 × 2 mm, reflexed; petiole 1–4 cm long Leaf lamina 3.5–9 × 1.5–3 cm, narrowly to broadly elliptic, apex acute, with a hastate base, narrowed above the basal lobes, markedly 3-nerved; basal lobes 5 × 2 mm, reflexed; petiole 1–4 cm long.
    Ocrea
    Ocrea 1–1.5 cm long, membranous, entire, caducous Ocrea 1–1.5 cm long, membranous, entire, caducous.
    Ecology
    In moist shady places, in high rainfall grassland, also as roadside weeds and in disturbed ground; 800–1900 m.
    Note
    Pawek (No. 12968) notes this species planted as a hedge at Ekwendeni in northern Malawi.
    Distribution
    Also in Uganda, Kenya, Tanzania and Dem. Rep. Congo. ZAM N, MAL N Zambia Malawi
    Flowers
    Flowers polygamous, bracteate, pedicellate, arranged in whorls of 2–6 flowers; pedicels 2–5 mm long, slender, unequal; whorls borne in leafless terminal, cylindrical or ± pyramidal panicles. Flowers polygamous, bracteate, pedicellate, arranged in whorls of 2–6 flowers; pedicels 2–5 mm long, slender, unequal; whorls borne in leafless terminal, cylindrical or ± pyramidal panicles
    Perianth
    Outer perianth segments brownish, 1.75–2 mm long, ovate, obtuse at the apex, membranous, deflexed and accrescent in fruit; inner perianth segments red or reddish-brown, pellucid, 5–7 mm in diameter, ± circular and wing-like when mature, rounded at the apex, cordate at the base with a squarish basal sinus, reticulately veined, with a small wart-like deflexed dorsal protuberance near the base. Outer perianth segments brownish, 1.75–2 mm long, ovate, obtuse at the apex, membranous, deflexed and accrescent in fruit; inner perianth segments red or reddish-brown, pellucid, 5–7 mm in diameter, ± circular and wing-like when mature, rounded at the apex, cordate at the base with a squarish basal sinus, reticulately veined, with a small wart-like deflexed dorsal protuberance near the base
    Stamens
    Stamens 6; filaments as long as the perianth segments, filiform; anthers 1.5 × 0.5 mm, cylindrical. Stamens 6; filaments as long as the perianth segments, filiform; anthers 1.5 × 0.5 mm, cylindrical
    Ovary
    Ovary 1.5 × 1 mm, trigonous. Ovary 1.5 × 1 mm, trigonous
    Fruits
    Nut brown, shiny, 2–2.5 mm long, trigonous. Nut brown, shiny, 2–2.5 mm long, trigonous.

    Images

    Distribution

    Native to:

    Burundi, Congo, Kenya, Malawi, Rwanda, Tanzania, Uganda, Zambia, Zaïre

    Rumex usambarensis (Engl.) Dammer appears in other Kew resources:

    Date Reference Identified As Barcode Type Status
    May 17, 1956 Holst, C. [2429], Tanzania K000244108 lectotype
    May 17, 1956 Michelmore, A. [711], Tanzania K000244109 holotype

    First published in Bot. Jahrb. Syst. 38: 61 (1905)

    Accepted by

    • Masharabu, T., Bigendako, M.J., Lejoly, J., Nkengurutse, J., Noret, N., Bizuru, E. & Bogaert, J. (2010). Etude analytique de la flore et de la végétation du Parc National de la Ruvubu, Burundi International Journal of Biological and Chemical Sciences 4: 834-856.
    • Pope, G.V., Polhill, R.M. & Martins, E.S. (eds.) (2006). Flora Zambesiaca 9(3): 1-277. Royal Botanic Gardens, Kew.
    • Troupin, G. (ed.) (1978). Flora du Rwanda 1: 1-413. Musee Royal de l'Afrique Centrale.
    • Graham, R.A. (1958). Flora of Tropical East Africa, Polygonaceae: 1-40.

    Literature

    Flora Zambesiaca
    • F.T.E.A., Polygonaceae: 7, fig. 2/1, 2 (1958).
    • Kew Bull. 11: 254 (1956)
    • Bot. Jahrb. Syst. 38: 61 (1905).
    Kew Backbone Distributions
    • Masharabu, T., Bigendako, M.J., Lejoly, J., Nkengurutse, J., Noret, N., Bizuru, E. & Bogaert, J. (2010). Etude analytique de la flore et de la végétation du Parc National de la Ruvubu, Burundi International Journal of Biological and Chemical Sciences 4: 834-856.
    • Pope, G.V., Polhill, R.M. & Martins, E.S. (eds.) (2006). Flora Zambesiaca 9(3): 1-277. Royal Botanic Gardens, Kew.
    • Sita, P. & Moutsambote, J.-M. (2005). Catalogue des plantes vasculaires du Congo, ed. sept. 2005: 1-158. ORSTOM, Centre de Brazzaville.
    • Troupin, G. (ed.) (1978). Flora du Rwanda 1: 1-413. Musee Royal de l'Afrique Centrale.
    Flora of Tropical East Africa
    • R. A. Graham in Kew Bulletin 1956: 254 (1956).
    • Dammer in A. Engler, Botanische Jahrbücher für Systematik, Pflanzengeschichte und Pflanzengeographie 38: 61 (1905).

    Sources

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

    Flora of Tropical East Africa
    Flora of Tropical East Africa
    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