Cyperus rotundus L.

First published in Sp. Pl.: 45 (1753)
This species is accepted
The native range of this species is Tropical & Subtropical Old World. It is a tuberous geophyte and grows primarily in the subtropical biome. It is used as animal food, a poison and a medicine, has environmental uses and for food.

Descriptions

Distribution
Biogeografic region: Caribbean. Elevation range: 0–1000 m a.s.l. Naturalised in Colombia. Colombian departments: Atlántico, Bolívar, Cesar, Córdoba, Cundinamarca, Magdalena, Meta, San Andrés y Providencia, Sucre, Tolima, Valle del Cauca.
Habit
Herb.
Conservation
IUCN Red List Assessment (2021): LC.
Ecology
Habitat according IUCN Habitats Classification: shrubland.
Vernacular
Coquito, Corocillo
[UPFC]

Cyperaceae, Miss S. S. Hooper. Flora of West Tropical Africa 3:2. 1972

Morphology General Habit
Common weed
Vegetative Multiplication Rhizomes
Slender, elongated rhizomes
Vegetative Multiplication Tubers
Rounded, fibre-covered tubers at the stem bases
Morphology Reproductive morphology Inflorescences
Large spikelets, characteristically dark red-brown, in short spikes
Ecology
Cultivated and other damp places.
[FWTA]

George R. Proctor (2012). Flora of the Cayman Isands (Second Edition). Royal Botanic Gardens, Kew

Vernacular
NUT GRASS
Morphology General Habit
Perennial with long, slender, fragile, deeply subterranean rhizomes bearing aromatic, nut-like tubers at wide intervals
Morphology Culms
Culms mostly 15–30 cm tall (rarely taller)
Morphology Reproductive morphology Inflorescences
Inflorescence compound with 2 or 3 erect, simple rays subtended by shorter leafy bracts
Morphology Reproductive morphology Inflorescences Spikelets
Spikelets few, 1–2 cm long (rarely much longer), loosely spreading
Morphology Reproductive morphology Fruits
Achenes 3-angled, shining black, 1.5–2 mm long.
Distribution
Grand Cayman. Pantropical, also extending into many warm-temperate regions.
Ecology
A persistent weed of lawns, gardens and open waste ground, this species easily regenerates from any tubers left in the ground.
[Cayman]

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

Type
Type: India, Herb. Hermann 1, 3: 36 (BM, lecto., chosen by Tucker in Syst. Bot. Monogr. 43: 100 (1994))
Morphology General Habit
Perennial or sometimes seemingly annual, 10–100 cm tall, gregarious, but not clump-forming, with a somewhat swollen culm-base arising from rather thick scalecovered stolons; nodules on roots white turning brown;  culms few, green, 1–3 mm wide, triangular, glabrous
Morphology Leaves
Leaves glossy green. Leaf blade linear, 10–40 × 0.2–0.8 cm wide, slightly M-shaped in cross-section, scabrid on margin and major veins, attenuate Leaf sheath green to reddish-brown.
Morphology Reproductive morphology Inflorescences Bracts
Involucral bracts leaf-like, 1–5, erect or spreading, lowermost 3–26 cm long, 2–9 mm wide
Morphology Reproductive morphology Inflorescences
Inflorescence a simple to compound anthela, primary branches 1–8, 0.5–12 cm long.
Morphology Reproductive morphology Inflorescences Spikelets
Spikelets in rather dense clusters, 3–15 per cluster, bright to golden to dark brown, linear-lanceolate and slightly flattened, 6–70 mm long, 1–2.5 mm wide, rachilla straight, remaining attached to rachis while lower glumes and nutlets are shed.
Morphology Reproductive morphology Inflorescences Bracts Glume
Glumes pale to dark reddish brown, ovate, 2.7–4.3 mm long, keel green, glabrous or slightly scabrid, with 1–2 veins on either side, apex obtuse
Morphology Reproductive morphology Flowers Androecium Stamens
Stamens 3, yellow, 1.6–2.2 mm long
Morphology Reproductive morphology Flowers Gynoecium Style
Style white, 3-branched
Morphology Reproductive morphology Fruits
Nutlet greyish to brown, obovoid, trigonous, 1.3–1.7 mm long, 0.5–1 mm wide, minutely papillose
Figures
Fig. 32, p212
Ecology
Swamps, damp sites, riverbanks, drainage lines in coastal bush or forest glades, common weed in rice and maize fields, seasonally wet grassland; 0–1950 m
Conservation
Least Concern
Note
After looking at all the East African material available, a few hundred specimens, I believe that for East Africa we are dealing with a single taxon, rotundus, with a few colour forms (and this was the basis on which specimens were mostly sorted, I think), and some variability in spikelet length and cross-section (the latter character used for distinguishing tuberosus) as well as in glume length. I am quite unable to write any key to the various forms that works on the bulk of the material; of course, the extremes are distinct, but there are more intermediate specimens than there are extreme ones. There are no constant qualitative characters separating the taxa, and hardly any convincing quantitative ones, either; geographically and habitat-wise there are no differences. Therefore I am reducing these names into synonyms of rotundus. Regarding the merkeri taxon, C.B. Clarke, when describing his new species C. merkeri only compared it to an unknown taxon, C. neuerensis; he gave the length of the culm as 30 cm. Kükenthal in E.P. 4, 20 (101) combined what was a full species ( merkeri) into a subspecies of rotundus. He did not give a key, but from his brief descriptions we can see he thought this subspecies differed from the typical one in longer culms (45–60 cm rather than 15–30 cm), and darker-coloured spikelets (dark dull red, rather than brown or dull red). Haines & Lye distinguished these two subspecies (again, without giving a key) by ‘its shorter glumes with a usually much darker colour’: glumes 2.7–3.2, rather than 3.3–4.3 mm; description of glume colour in the text overlaps for the two subspecies. Haines & Lye kept up four subspecies and varieties, based on Kükenthal taxa; Kükenthal had combined these taxa into C. rotundus. Differences between the taxa were only expressed in short sentences (rather than a key) and these have given me problems. Colour and degree of compression of the spikelet, plus glume length and glume apex configuration, were the characters used to distinguish these four taxa. Finally the taxon tuberosus was distinguished from rotundus by the original author, Rottbøll, based on a leafy (not almost leafless) culm base, a sub-simple anthela, and terete spikelets. Haines & Lye suggested that this subspecies “is very closely related to subsp. rotundus” but kept the taxa separate based on slightly longer and more acute glumes, and less terete spikelets, in tuberosus. A taxon decribed from coastal Kenya, var. taylorii, was said to differ in the tall culms (30–50 cm, quite within the range of typical rotundus); the large congested head, 3–6 cm wide of many crowded up to 3 cm long spikelets (again, well within normal range) and obtuse glumes 4–5 mm long (rather on the long side, but not excessively so). It was known only from the type.
Distribution
Range: Widespread in Africa; India Flora districts: U1 U2 U3 U4 K1 K2 K3 K4 K5 K6 K7 T1 T2 T3 T4 T5 T6 T7 T8 Z
[FTEA]

Bernal, R., G. Galeano, A. Rodríguez, H. Sarmiento y M. Gutiérrez. 2017. Nombres Comunes de las Plantas de Colombia. http://www.biovirtual.unal.edu.co/nombrescomunes/

Vernacular
chivasa, coco, coquillo, coquito, cortadera, junco de coquito
[UNAL]

Bernal, R., Gradstein, S.R. & Celis, M. (eds.). 2015. Catálogo de plantas y líquenes de Colombia. Instituto de Ciencias Naturales, Universidad Nacional de Colombia, Bogotá. http://catalogoplantasdecolombia.unal.edu.co

Distribution
Naturalizada en Colombia; Alt. 0 - 1000 m.; Islas Caribeñas, Llanura del Caribe, Valle del Cauca, Valle del Magdalena.
Morphology General Habit
Hierba
Conservation
Preocupación Menor
[CPLC]

M. Thulin et al. Flora of Somalia, Vol. 1-4 [updated 2008] https://plants.jstor.org/collection/FLOS

Morphology General Habit
Medium-sized perennial with a somewhat swollen (sometimes tuber-like) stem-base arising from slender to fairly robust stolons with rather remote scales
Morphology Stem
Stems 25–80 cm long and 1–4 mm thick, glabrous, triangular with many crowded leaves in the basal part
Morphology Leaves
Largest leaf-blades 15–40 cm long and 4–8 mm wide, flat or enrolled, scabrid at least on margin and major ribs; leaf-sheaths green to brown
Morphology Reproductive morphology Inflorescences
Spikes 1–5 x 1.5–7 cm with 4–15 erect or spreading spikelets Inflorescence a 3–15 cm long and 2–12 cm wide anthela consisting of 1(–many) sessile and 1–8 stalked spikes on 0.5–12 cm long peduncles with or without secondary spikes from the base of primary spikes; inflorescence-bracts 1–7, leafy, erect or spreading, the largest 3–20 cm long and 2–9 mm wide
Morphology Reproductive morphology Inflorescences Spikelets
Spikelets 6–70 x 1–2.5(–4) mm, linear-lanceolate, light to dark reddish brown with 8–35 flowers
Morphology Reproductive morphology Inflorescences Bracts Glume
Glumes 2.7–4.3 mm long, ovate, almost uncoloured or light to dark reddish brown with or without a narrow uncoloured margin and 1–2 nerves on each side of the midrib; midrib green, glabrous or scabrid ending in or below the obtuse apex
Morphology Reproductive morphology Flowers Gynoecium Style
Style 3-branched
Morphology Reproductive morphology Fruits
Nutlet 1.5–1.8 x 0.7–1 mm, obovate, triangular, greyish, minutely papillose.
Distribution
N2, 3; C2; S1–3 pantropical, andtemperate regions.
Ecology
Near sea-level to 500 m.
Vernacular
Gocondho, quunje (Somali).
Note
This is a very variable species, particularly as regards the colour and size of the glumes. The following subspecies apparently occur in Somalia: subsp. rotundus with 3.3–4.3 mm long light to dark reddish brown glumes, subsp. tuberosus (Rottb.) Kük. with 3.7–4 mm long light brown to uncoloured glumes, and subsp. merkeri (C.B. Cl.) Kük. with 2.7–3.2 mm long dark reddish brown to almost blackish glumes. Most collections are, however, too young to be referable to any of the subspecies.
[FSOM]

IUCN Red List of Threatened Species https://www.iucnredlist.org/species/158183/120153257

Conservation
LC - least concern
[IUCN]

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
India, Herb. Hermann 1, 3: 36 (BM lectotype), lectotypified by Tucker (1994).
Morphology General Habit
Perennial or sometimes seemingly annual, 10–100 cm tall, with a somewhat swollen culm- base arising from rather thick scale-covered stolons; nodules on roots white turning brown; gregarious, but not clump-forming; culms few, green, 1–3 mm wide, triangular, glabrous
Morphology Leaves
Leaves glossy green; leaf sheath green to reddish-brown; leaf blade linear, 10–40 × 0.2–0.8 cm wide, slightly M-shaped in cross-section, scabrid on margin and major veins, attenuate
Morphology Reproductive morphology Inflorescences Bracts
Involucral bracts leaf-like, 1–5, erect or spreading, lowermost 3–26 cm long, 2–9 mm wide
Morphology Reproductive morphology Inflorescences
Inflorescence a simple to compound anthela, primary branches 1–8, 0.5–12 cm long; spikelets in rather dense clusters, 3–15 per cluster, bright to golden to dark brown, linear-lanceolate and slightly flattened, 6–70 mm long, 1–2.5 mm wide, rachilla straight, remaining attached to rachis while lower glumes and nutlets are shed; glumes pale to dark reddish brown, ovate, 2.7–4.3 mm long, keel green, glabrous or slightly scabrid, with 1–2 veins on either side, apex obtuse
Morphology Reproductive morphology Flowers Androecium Stamens
Stamens 3, yellow, 1.6–2.2 mm long
Morphology Reproductive morphology Flowers Gynoecium Style
Style white, 3-branched
Morphology Reproductive morphology Fruits
Nutlet greyish to brown, obovoid, trigonous, 1.3–1.7 mm long, 0.5–1 mm wide, minutely papillose.
Distribution
Botswana, Zambia, Zimbabwe, Malawi, Mozambique. Widespread in Africa; India.
Ecology
Swamps, damp sites, riverbanks, drainage lines in coastal bush or forest glades, common weed in rice and maize fields, seasonally wet grassland; 0–1950 m.
Conservation
Least Concern; one of the most widespread tropical species and often included among ‘the World’s worst weeds’.
[FZ]

M. Thulin et al. Flora of Somalia, Vol. 1-4 [updated 2008] https://plants.jstor.org/collection/FLOS

Type
N3, “Dudo” in “Shol” plain, Merla, Azzaroli & Fois s.n. (FT holo.)
Morphology General Habit
Robust perennial; stems 30–40 cm long and 1.5–3 mm thick
Morphology Leaves
Leaf-blades to 40 cm long and 4-8 mm wide, flat
Morphology Reproductive morphology Inflorescences
Inflorescence a lax anthela to c. 10 cm long and wide, consisting of many sessile as well as stalked spikes or clusters of spikes Spikes c. 2 x 3–4 cm, consisting of 4–10 spikelets mostly spreading at right angles; rhachis 1–5 mm long
Morphology Reproductive morphology Inflorescences Spikelets
Spikelets 15–22 x 3–4 mm, linear, 20–25-flowered; rhachilla prominently zigzag with rather widely spaced flowers
Morphology Reproductive morphology Inflorescences Bracts Glume
Glumes 3–3.5 mm long, ovate, reddish brown without pallid margin, with 3–5 slender nerves on each side of the green midrib which is excurrent into a c. 0.2–0.3 mm long mucro
Morphology Reproductive morphology Flowers Gynoecium Style
Style 3-branched
Morphology Reproductive morphology Fruits
Nutlet 1.8 x 0.7–0.8 mm, obovate, prominently triangular, greyish, minutely papillose.
Distribution
N3 not known elsewhere.
Ecology
Altitude range 350–400 m.
[FSOM]

Uses

Use Animal Food
Used as animal food.
Use Environmental
Environmental uses.
Use Gene Sources
Used as gene sources.
Use Food
Used for food.
Use Materials
Used as material.
Use Medicines
Medical uses.
Use Poisons
Poisons.
[UPFC]

Use
The tubers contain an aromatic oil that has been used in some countries in perfume and in medicines as a remedy for digestive disorders.
[Cayman]

Use
Root nodules roasted and eaten ( Harwood 60), or used as beads by Turkana ( Mwangangi 1446); roots chewed raw for coughs and colds ( Meyerhoff 74)
[FTEA]

Common Names

English
Nutgrass, Nutsedge, Purple nutsedge

Sources

  • Catálogo de Plantas y Líquenes de Colombia

    • http://creativecommons.org/licenses/by-nc-sa/3.0
  • Flora Zambesiaca

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

    • Flora of Somalia
    • 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
  • Flora of West Tropical Africa

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

    • Flora of the Cayman Islands
    • 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/
  • 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
  • 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/
  • Universidad Nacional de Colombia

    • ColPlantA database
    • http://creativecommons.org/licenses/by-nc-sa/3.0
  • Useful Plants and Fungi of Colombia

    • http://creativecommons.org/licenses/by-nc-sa/3.0