Cyperaceae - Cyperus rotundus L.

Description Herbácea, perenne; rizoma con entrenudos largos, muy fino, de c. 1 mm de diámetro, generalmente reticulado, con frecuencia muy ramificado, formando una malla; tubérculos 8–14 × 4–12 mm, que se desarrollan en las ramificaciones de los rizomas, generalmente fusiformes o subovoides, negruzcos. Tallos (10)17–30(55) cm, solitarios, rectos, trígonos. Hojas (15)20–28(31) × 0,2–0,5 cm, generalmente de menor longitud que el tallo, basales o casi, que dejan desnudo el tallo en su mitad superior, planas o, a veces, un poco aquilladas, antrorso-escábridas en los márgenes y el nervio medio por el envés, e incurvadas hacia el nervio, glaucas, sobre todo por el envés; lígula formada por un borde membranoso hialino, corto. Inflorescencia terminal, en antela simple o compuesta, con 3–8 radios primarios hasta de 12(18) cm, desiguales, trígonos, con 3–11 espiguillas dispuestas en espiga en el ápice de los radios terminales; porción del eje que porta las espiguillas de longitud generalmente menor que la de las propias espiguillas; brácteas (2)3–6(8), planas, patentes, antrorso-escábridas en los márgenes, la inferior de (7)10–16(23) × 0,2–0,5 cm, de longitud mucho mayor que la inflorescencia; espiguillas (8)14–31(65) × 1,5–3 mm, erecto-patentes, lanceoladas, agudas, comprimidas, con 12–30 flores; raquis recto, con un ala membranácea hialina. Glumas 2,6–4,3 × 0,75–1,5(2,4) mm, dísticas, densamente imbricadas, ovadas o elípticas, obtusas o, a veces, mucronuladas, membranáceas, de color pardo rojizo, con una banda verdosa, con 5–7 nervios visibles pero no prominentes. Estambres 3; anteras 1,5 × 0,4–0,7 mm, de contorno oval u obovado, o con ápice truncado. Aquenios 1,2–1,7 × 0,8–1,1 mm, de contorno obovado, trígonos, de color pardo oscuro o negruzco en la madurez. [details]

Description Perennials. Stolons slender, with ellipsoidal tubers. Culms solitary, rarely 2 laxly tufted, 15-90 cm tall, slightly...

Description Perennials. Stolons slender, with ellipsoidal tubers. Culms solitary, rarely 2 laxly tufted, 15-90 cm tall, slightly slender, triquetrous, smooth, base swollen into a tuber, leaved at basal part. Leaves equaling or shorter than culm; sheath brown, usually disintegrating into fibers; leaf blade bluish green, 2-5 mm wide, ± flat. Involucral bracts 2 or 3(-5), longer to sometimes shorter than inflorescence. Inflorescence a simple or compound anthela; rays (2 or)3-10, mostly to 12 cm, unequal in length, spreading. Spikes obdeltoid, with 3-10 slightly laxly arranged spikelets. Spikelets obliquely spreading, linear, 1-3 cm × 1.5-2 mm, 8-28-flowered; rachilla wings white, slightly broad, hyaline. Glumes blood-red to purplish brown on both surfaces but middle green, subdensely imbricate, ovate to oblong-ovate, ca. 3 mm, 5-7-veined (fading some distance before margin), apex acute to obtuse and muticous. Stamens 3; anthers linear; connective prominent beyond anthers. Style long; stigmas 3, longer than style, exserted from glume. Nutlet obovoid-oblong, 1/3-2/5 as long as subtending glume, 3-sided, puncticulate. Fl. and fr. May-Nov. 2n = 80, 84, 96, 100, 104, 108, 110, 112, 116, 124, 132, 138, 160, ca. 200. [details]

Taxonomic remark Source in seed data: wcs Update namepublishedIn from Sp. Pl. 45 1753 to Sp. Pl. : 45 (1753), information provided by Alan...

Taxonomic remark Source in seed data: wcs Update namepublishedIn from Sp. Pl. 45 1753 to Sp. Pl. : 45 (1753), information provided by Alan E. on email Jun. 07 2021 More details could be found in The Plant Lis [details]

Taxonomic citation

Cyperaceae Working Group. (2025). [see How to cite]. Global Cyperaceae Database. Cyperus rotundus L.. Accessed at: https://cyperaceae.org/aphia.php?p=taxdetails&id=1491857 on 2026-09-23

Taxonomic edit history

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2021-03-16 12:37:04Z

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2023-09-05 06:47:53Z

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Larridon, Isabel

2024-12-10 11:47:54Z

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Licensing

The webpage text is licensed under a Creative Commons Attribution 4.0 License

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Nomenclature

original description (of Cyperus nubicus C.B.Clarke) Clarke, C. B. (1901). Cyperaceae. In: Thiselton-Dyer, W.T. (ed.), Flora of Tropical Africa. Vol. 8 (Pt. 1): pp. 266–384. London: L. Reeve & Co., available online at https://www.biodiversitylibrary.org/page/379171#page/278/mode/1up
page(s): 360 [details]

original description (of Cyperus taylorii C.B.Clarke) Clarke, C. B. (1901). Cyperaceae. In: Thiselton-Dyer, W.T. (ed.), Flora of Tropical Africa. Vol. 8 (Pt. 1): pp. 266–384. London: L. Reeve & Co., available online at https://www.biodiversitylibrary.org/page/379171#page/278/mode/1up
page(s): 367 [details]

basis of record Plants of the World Online (POWO). , available online at https://powo.science.kew.org/ [details]

Taxonomy

taxonomy source Luceño, M., Castroviejo, S., Jiménez-Mejías, P. (2008). Cyperaceae. In: Castroviejo, Luceño, M., Galán, A., Jiménez-Mejías, P., Cabezas, F., Medina, L. (eds). Flora iberica. Plantas vasculares de la Península Ibérica e Islas Baleares. Vol. XVIII. Madrid: CSIC., available online at https://bibdigital.rjb.csic.es/records/item/12958-flora-iberica-vol-18-cyperaceae-pontederiaceae?offset=, http://www.floraiberica.es/PHP/familias_lista_.php?familia=Cyperaceae [details]

Other

additional source Li, B. Z.; Zhang, S. R. (2024). An updated species checklist and taxonomic synopsis of Cyperaceae in China. <em>Biodiversity Science.</em> 32(7): 24106., available online at https://doi.org/10.17520/biods.2024106 [details] Available for editors

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Translation Herbaceous perennial; rhizome with long internodes, very slender, c. 1 mm in diameter, generally reticulate and often highly branched, forming a network; tubers 8–14 × 4–12 mm, developing on the rhizome branches, usually fusiform or subovoid, blackish. Stems (10)17–30(55) cm, solitary, erect, trigonous. Leaves (15)20–28(31) × 0.2–0.5 cm, generally shorter than the stem, basal or nearly so, leaving the upper half of the stem bare; blades flat or sometimes slightly keeled, antrorsely scabrid along the margins and the midrib on the abaxial surface, incurved toward the midrib, glaucous, especially beneath; ligule formed by a short, hyaline membranous margin. Inflorescence terminal, in a simple or compound anthela, with 3–8 primary rays up to 12(18) cm long, unequal, trigonous, bearing 3–11 spikelets arranged in spikes at the apex of the terminal rays; the axis portion bearing the spikelets usually shorter than the spikelets themselves; bracts (2)3–6(8), flat, spreading, antrorsely scabrid on the margins, the lowest (7)10–16(23) × 0.2–0.5 cm, much longer than the inflorescence; spikelets (8)14–31(65) × 1.5–3 mm, erect-spreading, lanceolate, acute, compressed, with 12–30 flowers; rachilla straight, with a hyaline membranous wing. Glumes 2.6–4.3 × 0.75–1.5(2.4) mm, distichous, densely imbricate, ovate to elliptic, obtuse or sometimes mucronulate, membranous, reddish-brown, with a greenish band and 5–7 visible but not prominent nerves. Stamens 3; anthers 1.5 × 0.4–0.7 mm, oval to obovate, or with a truncate apex. Achenes 1.2–1.7 × 0.8–1.1 mm, obovate in outline, trigonous, dark brown to blackish at maturity. [details]

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