Hydrocharitaceae
Lagarosiphon

Lagarosiphon major (Ridl.) Moss

First published in Trans. Roy. Soc. South Africa 16: 193 (1928)
This species is accepted
The native range of this species is S. Tropical & S. Africa. It is a hydroperennial and grows primarily in the subtropical biome.

Descriptions

J. R. Timberlake, E. S. Martins (2009). Flora Zambesiaca, Vol 12 (part 2). Royal Botanic Gardens, Kew

Type
Type South Africa, Umdizine R., 1880, Cooper 17 (BM lectotype selected by Symoens & Triest (1983), BOL, G, K, PRE, W, Z).
Morphology Stem
Stems firm, c.3 mm wide
Morphology Leaves
Leaves alternate, occasionally whorled, spreading or recurved, linear, 6.5–25 2–4.4 mm, firm, mostly opaque, apex mostly obtuse, rarely acute or acuminate; epidermal cells predominantly equal-sided; margins with 2 (or 3 at leaf base) rows of sclerenchyma fibres, almost translucent, each side bearing 50–100 teeth, not on protuberances, relatively short, pointing upwards, blunt; central area narrow, consisting of some mesophyll, mostly with air lacunae and aerenchyma, no sclerenchyma fibres
sex Male
Male inflorescence with spathe containing c.50 flower buds, valves ovate, 3–5 1.9–2.7 mm, bearing 3–18 small teeth; male flowers with pinkish perianth, sepals 1.25 0.66 mm, petals 1 0.35 mm; stamens 1.25 mm long, staminodes c.2 mm long
sex Female
Female inflorescence with spathe valves ovate to narrowly ovate, 3.5(5.5) × 1.4(2.5) mm, bearing 2–3 small teeth; female flowers with pinkish perianth segments c.1.25 mm long, sepals somewhat broader than petals; ovary containing 10–12 ovules, stigma purplish
Morphology Reproductive morphology Fruits
Capsule ovoid to narrowly ovoid, tapered above, 4–5 c.1 mm
Morphology Reproductive morphology Seeds
Seeds narrowly ellipsoid, 2 × 0.7 mm
Distribution
Botswana, Zimbabwe. Also in South Africa from the northern provinces to the Eastern Cape.
Ecology
Widely introduced, often invasive and troublesome in Europe and New Zealand. Dams and lakes; 900–2000 m.
Conservation
Conservation notes An invasive introduced species.
[FZ]

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/185287/8382399

Conservation
LC - least concern
[IUCN]

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

  • 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 2025. 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 2025. 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