Cyperaceae
Eleocharis

Eleocharis dulcis (Burm.f.) Trin. ex Hensch.

First published in Vita Rumphii: 186 (1833)
This species is accepted
The native range of this species is Tropical & Subtropical Old World. It is a perennial or tuberous geophyte and grows primarily in the subtropical or tropical biome.

Descriptions

Cyperaceae, K Hoenselaar, B. Verdcourt & H. Beentje. Hypolytrum, D Simpson. Fuirena, M Muasya. Flora of Tropical East Africa. 2010

Type
Type: “India”, no further indication
Morphology General Habit
Robust perennial 30–120 cm tall, with tufted culms from a contracted base.
Morphology Culms
Culms bright green, rounded (rarely quadrangular), hollow, 4–8 mm thick, septate at 3–10 cm intervals, contracted to 2–3 mm immediately below the inflorescence.
Morphology Roots
Roots orange, turning red-brown.
Vegetative Multiplication Stolons
Stolons white when young, to 30 cm long and to 6 mm across, with 5–8 mm long sheaths at the nodes.
Morphology Leaves Leaf sheaths
Sheaths to 1/2 or 1/3 of the culm height, ending in a triangular lobe
Morphology Reproductive morphology Inflorescences
Inflorescence a pale green cylindric spikelet 25–50 mm long, 2–6 mm across, narrower than the culm, sometimes aborting and leaving a scar; lowest glumes shorter than upper, most closely overlapping, green to pale brown with pale margin, 4–6 mm long, with wide transparent margin and rounded apex.
Morphology Reproductive morphology Flowers Perianth
Perianth of ± 7 long slender bristles with recurved spine-like teeth all over
Morphology Reproductive morphology Flowers Androecium Stamens
Stamens white, 3.
Morphology Reproductive morphology Flowers Androecium Stamens Anthers
Anthers elongate
Morphology Reproductive morphology Flowers Gynoecium Style
Style white, with 2–3 branches
Morphology Reproductive morphology Fruits
Nutlet 2–2 mm long excluding the long brown triangular appendage, smooth
Figures
Fig 7, p38
Ecology
Swamps, shallow parts of lakes, often in standing water; may be locally common or form pure stands; 0–2150 m
Note
The only Eleocharis in our area with transverse septa. This is a widespread species, cultivated in Asia: “Chinese water chestnut”.
Distribution
Range: Togo, Congo-Kinshasa, Zambia, Mozambique, Zimbabwe, Botswana, South Africa; Madagascar, Asia to Queensland and Polynesia Flora districts: U3 U4 K4 K7 T4 T6 T7 T8
[FTEA]

J. Browning, K.D. Gordon-Gray†, M. Lock, H. Beentje, K. Vollesen, K. Bauters, C. Archer, I. Larridon, M. Xanthos, P. Vorster, J. Bruhl, K. Wilson and X. Zhang (2020). Flora Zambesiaca Volume: 14: Cyperaceae. M.Á. García, J.R. Timberlake (Eds). Kew Publish

Type
East Indies, based on Cyperus dulcis Rumph., Herb. Amb. 6: 7 (1750).
Morphology General Habit
Perennial; rhizome abbreviated linking shoot bases into tufts; stolons elongate, nodose, lacking tubers, terminating in erect, rounded, hollow culms to 150 cm tall with septa 3–10 cm apart (contracted upwards to 2–3 cm)
Morphology Leaves
Leaves reduced to nodal sheaths with sloping mouth, blade a small triangular outgrowth
Morphology Reproductive morphology Inflorescences
Inflorescence a terminal cylindrical spike (a solitary spikelet), 25–50 × 2–6 mm, narrower than its culm
Morphology Reproductive morphology Inflorescences Bracts Glume
Glumes closely imbricate, 4–6 mm long, not keeled, veins numerous (× 20 magnification needed to observe distally), ovate with dark brown submarginal band and a membranous ± colourless margin
Morphology Reproductive morphology Flowers Perianth
Perianth usually of 7 strong bristles exceeding mature nutlet, margins barbellate, retrorse
Morphology Reproductive morphology Flowers Androecium Stamens
Stamens 3
Morphology Reproductive morphology Flowers Gynoecium Style
Style bifid or trifid
Morphology Reproductive morphology Fruits
Nutlet 2–2.4 mm long, ± round, ovate in outline, surface smooth, persistent style base long-triangular, shrinking on drying.
Distribution
Botswana, Zambia, Mozambique. In Uganda, Kenya, Tanzania and South Africa (KwaZulu-Natal); also in Madagascar, Asia, Australia and Polynesia.
Ecology
In freshwater pans or seepage areas and margins of lakes; 10–1400 m.
Conservation
Widespread; not threatened.
Recognition
Plants have septate culms which can be noticed on breakage.
Vernacular
The cultivated form of this species is known as Chinese Water Chestnut. Robinson notes the vernacular name in Zambia is nasunga.
[FZ]

IUCN Red List of Threatened Species https://www.iucnredlist.org/species/169077/1270989

Conservation
LC - least concern
[IUCN]

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]

Uses

Use
The plant is burnt and used as a salt, while the stems may be used in basket making.
[FZ]

Common Names

unknown
Chinese water chestnuts

Sources

  • Angiosperm Extinction Risk Predictions v1

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

  • EBC Common Names

    • Common Names from Kew's Economic Botany Collection https://www.kew.org/science/collections-and-resources/collections/economic-botany-collection

  • 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/

  • 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 2026. 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 2026. 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

  • Plants and People Africa

    • Common Names from Plants and People Africa http://www.plantsandpeopleafrica.com/
    • © Plants and People Africa http://www.plantsandpeopleafrica.com http://creativecommons.org/licenses/by/3.0/