Cyperaceae
Cyperus

Cyperus diurensis Boeckeler

First published in Flora 62: 556 (1879)
This species is accepted
The native range of this species is Ethiopia to S. Tropical Africa. It is a perennial or rhizomatous geophyte and grows primarily in the seasonally dry tropical biome.

Descriptions

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

Type
Type: Sudan, Djur, Seriba Ghattas, Schweinfurth 198, series III (B, holo.; K!, iso.)
Morphology General Habit
Perennial, up to 83 cm tall, with a slightly swollen culm base with 1–10 cm long slender stolons.
Morphology Culms
Culms few, 25–80 cm long, 0.7–2.5 mm wide, trigonous, glabrous
Morphology Leaves
Leaves up to 45 cm long. Leaf blade linear, flat or sometimes folded, 22–39 cm long, 2–3.8 mm wide, scabrid on margin and primary vein, apex acuminate Leaf sheath 2.5–9 cm long.
Morphology Reproductive morphology Inflorescences Bracts
Involucral bracts leaf-like, spreading to reflexed, 3–6, lowermost 5.5–30 cm long, 1.9–3.2 mm wide
Morphology Reproductive morphology Inflorescences
Inflorescence capitate, a solitary globose head, 10–20 mm long, 11–22 mm wide.
Morphology Reproductive morphology Inflorescences Spikelets
Spikelets many per inflorescence, ovate-lanceolate, 6.5–14.1 mm long, 2.1–4 mm wide, falling off entire when mature.
Morphology Reproductive morphology Inflorescences Bracts Glume
Glumes whitish with a reddish-brown tinge, especially near apex, ovate to boatshaped, 4–5.1 mm long, 1.6–2 mm wide, keel, apex obtuse, frayed
Morphology Reproductive morphology Flowers Androecium Stamens
Stamens 2–3.
Morphology Reproductive morphology Flowers Androecium Stamens Filaments
Filaments ± 5.4 mm long.
Morphology Reproductive morphology Flowers Androecium Stamens Anthers
Anthers 2.2–2.7 mm long
Morphology Reproductive morphology Fruits
Nutlet grey-brown, ellipsoidoblong, trigonous, 1.7–2 mm long, 0.7–0.8 mm wide, minutely papillose.
Ecology
In grassland, woodland and rocky outcrops; sea-level up to 1800 m
Conservation
Least Concern due to its wide distribution and common habitat
Distribution
Range: Congo-Kinshasa, Rwanda, Ethiopia, Sudan Flora districts: U1 K7 T1 T3 T4 T5 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
Sudan, Djur, Seriba Ghattas, 20.viii.1869, Schweinfurth 198, series III (B holotype, K).
Morphology General Habit
Perennial, up to 80 cm tall, with a slightly swollen culm base bearing several 1–10 cm long slender horizontal brown-scaly rhizomes about 2 mm in diameter; culms few, 25–80 cm long, 0.7–2.5 mm wide, trigonous, glabrous
Morphology Leaves
Leaves up to 45 cm long; leaf sheath 2.5–9 cm long; leaf blade linear, flat or sometimes folded, 22–39 cm long, 2–3.8 mm wide, scabrid on margin and primary vein, apex acuminate
Morphology Reproductive morphology Inflorescences Bracts
Involucral bracts leaf-like, spreading to reflexed, 3–6, lowermost 5.5–30 cm long, 1.9–3.2 mm wide
Morphology Reproductive morphology Inflorescences
Inflorescence capitate, a solitary globose head, 10–20 × 11–23 mm wide; spikelets many per inflorescence, ovate-lanceolate, 6.5–14.1 × 2.1–4 mm wide, falling off entire when mature; glumes whitish with a reddish-brown tinge, especially near apex, ovate to boat-shaped, 4–5.1 ×1.6–2 mm wide, keel, apex obtuse, frayed
Morphology Reproductive morphology Flowers Androecium Stamens
Stamens 2–3; filaments c. 5.4 mm long; anthers 2.2–2.7 mm long
Morphology Reproductive morphology Fruits
Nutlet grey-brown, ellipsoid-oblong, trigonous, 1.7–2 × 0.7–0.8 mm wide, minutely papillose.
Distribution
Zambia, Zimbabwe, Malawi. Also in Ethiopia, Sudan, Uganda, Kenya, Tanzania, Rwanda and D.R. Congo.
Ecology
In grassland and woodland, often in shallow sandy soil over rocky outcrops and inselbergs; (5)1000–1400(1800) m.
Conservation
Least Concern because of its wide distribution.
[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]

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 Tropical East Africa

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

  • Herbarium Catalogue Specimens

    • 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 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