Acanthus montanus (Nees) T.Anderson

First published in J. Proc. Linn. Soc., Bot. 7: 37 (1863)
This species is accepted
The native range of this species is Sierra Leone, Benin to S. Chad and Zambia. It is a subshrub or shrub and grows primarily in the seasonally dry tropical biome.

Descriptions

Extinction risk predictions for the world's flowering plants to support their conservation (2024). Bachman, S.P., Brown, M.J.M., Leão, T.C.C., Lughadha, E.N., Walker, B.E. https://nph.onlinelibrary.wiley.com/doi/full/10.1111/nph.19592

Conservation
Predicted extinction risk: not threatened. Confidence: confident
[AERP]

IUCN Red List of Threatened Species https://www.iucnredlist.org/species/185329/8390038

Conservation
LC - least concern
[IUCN]

Acanthaceae, H. Heine. Flora of West Tropical Africa 2. 1963

Morphology General Habit
Plant up to 6 ft. high, stems woody, sparsely branched
Morphology Leaves
Leaves dark glossy green above, paler beneath, papery, scabrid bracts and calyx-lobes whitish with green veins
Ecology
In high forest.
[FWTA]

J. R. Timberlake, E. S. Martins (2013). Flora Zambesiaca, Vol 8 (5) Acanthaceae Part 1. Royal Botanic Gardens, Kew

Type
Bioko (Fernando Po), xi.1841, Vogel 239 (K holotype).
Morphology General Habit
Shrubby herb or shrub to 1.5(?4) m tall; young stems sparsely and finely puberulous at nodes
Morphology Leaves
Leaves subglabrous to finely and sparsely puberulous on midrib and larger veins; petiole 0.2–1.3 cm long; lamina elliptic to obovate in outline, largest 20–28 × 7–12 cm, deeply lobed with oblong- triangular spine-tipped lobes, each lobe with 1–3 teeth on one or both sides; apex acute to cuspidate, spine-tipped; base cuneate to truncate, a pair of large spines right at base, sometimes detached
Morphology Reproductive morphology Inflorescences
Spikes solitary (rarely also 2 from upper axils), 9–31 cm long; rachis glabrous or with few scattered hairs, with stalked capitate glands upwards, with or without one pair of sterile bracts at base; bracts green, elliptic to obovate, glabrous to finely puberulous, 2.7–3.3 cm long in middle of spike, long triangular straight or recurved spine-tipped apical part 5–9 mm, with 4–7 large and small teeth per side (small sometimes absent), longest 6–8 mm long, small teeth inserted between large; bracteoles 1.9–2.6 cm long, linear-lanceolate, with 2–3 teeth per side
Morphology Reproductive morphology Flowers Calyx
Calyx green, glabrous to puberulous; dorsal sepal elliptic-oblong, 3–3.5 cm long, gradually narrowing to acute spine-tipped apex, with (1)3–7 lateral teeth on each side; ventral sepal ovate- oblong, 3–3.5 cm long, gradually narrowing to bifid apex with 2 triangular spine-tipped teeth 5–9 mm long, often themselves toothed, 1–2 central teeth in the gap, laterally also with 3–5 teeth per side; lateral sepal ovate or narrowly so, 1.2–2.3 cm long, acute to cuspidate, without lateral teeth
Morphology Reproductive morphology Flowers Corolla
Corolla white with pink to pale pink veins; tube c.3 mm long below thickened rim, rim c.4 mm long with broad dorsal shallow split; limb spreading, 5-lobed, 3–4.5 × 3–4 cm, glabrous to sparsely puberulous below, large glandular ‘blisters’ towards base, glabrous above, 3 central lobes much longer than 2 lateral; callus not grooved
Morphology Reproductive morphology Flowers Androecium Stamens Filaments
Filaments 1.5–2.2 cm long, two dorsal glabrous or sparsely hairy near base; anthers 9–11 mm long, without or with sparse long curly hairs on sides, sessile glands dorsally
Morphology Reproductive morphology Fruits
Capsule (from Angolan material) c.2.5 cm long
Morphology Reproductive morphology Seeds
Seeds rhomboid, c.9 mm long, sparsely puberulous.
Distribution
Zambia. Also in Nigeria, Cameroon, Equatorial Guinea (incl. Bioko), Sao Tomé, Gabon, Central African Republic, Congo and Angola.
Ecology
Riverine forest with Syzygium (mushitu); c.1000 m.
Conservation
Local in Flora area but widespread elsewhere; not threatened.
[FZ]

Sources

  • Angiosperm Extinction Risk Predictions v1

    • Angiosperm Threat Predictions
    • http://creativecommons.org/licenses/by/4.0
  • Flora Zambesiaca

    • Flora Zambesiaca
    • http://creativecommons.org/licenses/by-nc-sa/3.0
  • Flora of West Tropical Africa

    • Flora of West Tropical 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/
  • IUCN Categories

    • IUCN Red List of Threatened Species
    • http://creativecommons.org/licenses/by-nc-sa/3.0
  • Kew Backbone Distributions

    • The International Plant Names Index and World Checklist of Vascular Plants 2024. Published on the Internet at http://www.ipni.org and https://powo.science.kew.org/
    • © Copyright 2023 World Checklist of Vascular Plants. http://creativecommons.org/licenses/by/3.0
  • Kew Names and Taxonomic Backbone

    • The International Plant Names Index and World Checklist of Vascular Plants 2024. Published on the Internet at http://www.ipni.org and https://powo.science.kew.org/
    • © Copyright 2023 International Plant Names Index and World Checklist of Vascular Plants. http://creativecommons.org/licenses/by/3.0
  • Kew Science Photographs

    • Copyright applied to individual images