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  1. Family: Acanthaceae Juss.
    1. Genus: Acanthus L.
      1. Acanthus eminens C.B.Clarke

        This species is accepted, and its native range is Ethiopia to South Sudan and Central Kenya.

    [FTEA]

    Acanthaceae (part 1), Kaj Vollesen, Flora of Tropical East Africa, 2008

    Habit
    Shrubby herb or shrub to 3 m tall; young stems glabrous.
    Leaves
    Leaves with petiole 0.5–2(–2.5) cm long; lamina narrowly elliptic to elliptic or obovate in outline, largest 13–37 × 5–15 cm, deeply lobed with large triangular spine-tipped lobes, each lobe with a spine on antrorse side, apex acuminate to cuspidate, spine-tipped, base attenuate to cuneate, glabrous; each node with one to several persistent sharp terete straw-coloured interpetiolar downwardly directed pungent pale yellow spines to 1.5 cm long, occasionally some with a small lamina.
    Inflorescences
    Cymes solitary or also 2 from upper leaf-pair, (5–)7–30 cm long; rachis upwards pubescent with hairs and few to many short to long capitate glands, with several pairs of sterile bracts at base, sometimes merging into the vegetative leaves; bracts green to purplish, ovate to elliptic, finely puberulous to sparsely pubescent and upwards with few to many stalked capitate glands, 1.4–2.8 cm long in middle of cyme, spine-tipped and with 4–8 teeth per side (rarely entire); bracteoles subulate to linear, 5–11 mm long, entire.
    Calyx
    Calyx green to purplish, puberulous and with few to many stalked capitate glands; dorsal and ventral sepals longer than bract, oblong-obovate, similar or dorsal slightly longer, 2.1–4 cm long, dorsal entire or 2–3-toothed, ventral 2–3-toothed or irregularly toothed, lateral lanceolate, 1.3–2.5 cm long, acuminate.
    Corolla
    Corolla dark blue to dark purple (rarely pale blue to almost white); tube 4–5 mm long below thickened rim which is 3–4 mm long; limb 5-lobed, 3.5–5 × 3.5–5 cm, below puberulous with hairs and capitate glands, above glabrous; callus with narrow central groove.
    Filaments
    Filaments 1.7–2.2 cm long, glabrous or with stalked glands near apex; anthers 6–9 mm long, densely glandular dorsally.
    Fruits
    Capsule 2.3–2.5 cm long.
    Seeds
    Seed ellipsoid to round, 9–10 mm long, glabrous.
    Distribution
    Range: Uganda. Range: Sudan (Imatong Mts), Ethiopia Range: Kenya. Flora districts: U3 K3 K4 K5 K6 Range: Sudan (Imatong Mts), Ethiopia
    Ecology
    Primary and disturbed wet evergeen montane forest, forest margins, secondary grassland, often forming large stands, occasionally used as a hedge plant; (1200–)1500–2600 m
    Note
    Always easily recognised by the spinose nodes and large sepals combined with small bracts. This species must surely also occur in the N Ugandan mountains ( U 1) as it is common in the Imatong Mts on the Sudan side.

    Images

    Distribution

    Native to:

    Ethiopia, Kenya, Sudan, Uganda

    Other Data

    Acanthus eminens C.B.Clarke appears in other Kew resources:

    Date Reference Identified As Barcode Type Status
    Feb 11, 1897 Scott Elliot, G.F. [6926], Kenya K000394426 holotype

    Bibliography

    First published in D.Oliver & auct. suc. (eds.), Fl. Trop. Afr. 5: 107 (1899)

    Accepted by

    • Darbyshire, I., Kordofani, M., Farag, I., Candiga, R. & Pickering, H. (eds.) (2015). The Plants of Sudan and South Sudan: 1-400. Kew publishing, Royal Botanic Gardens, Kew.
    • Fischer, E., Rembold, K., Althof, A. & Obholzer, J. (2010). Annotated checklist of the vascular plants of Kakamega forest, Western province, Kenya Journal of East African Natural History 99: 129-226.
    • Vollesen, K. (2008). Flora of Tropical East Africa, Acanthaceae(1): 1-285.
    • Hedberg, I., Kelbessa, E., Edwards, S., Demissew, S. & Persson, E. (eds.) (2006). Flora of Ethiopia and Eritrea 5: 1-690. The National Herbarium, Addis Ababa University, Ethiopia & The Department of Systematic Botany, Upps.
    • Govaerts, R. (1995). World Checklist of Seed Plants 1(1, 2): 1-483, 529. MIM, Deurne.

    Literature

    Flora of Tropical East Africa

    • K.B. 62: 239 (2007).
    • F.E.E. 5: 355 (2006)
    • Biol. Skr. 51(2): 435 (2005)
    • Lebrun & Stork, Enum. Pl. Afr. Trop. 4: 466 (1997)
    • K.T.S.L.: 596 (1994)
    • U.K.W.F., ed. 2: 274 (1994)
    • Blundell, Wild Fl. E. Afr.: 385, fig. 601 (1987)
    • E.P.A.: 952 (1964)
    • K.T.S.: 16 (1961)
    • F.P.S. 3: 166 (1956)
    • K.B. 1933: 94 (1934)
    • F.T.A. 5: 107 (1899)

    Sources

    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 2020. 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 2020. 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