Rhynchospora Vahl
  • Enum. Pl. 2: 229. 1805.
  • Beak-rush, rhynchospore [Greek rhynchos, snout, and spora, seed]

Cite taxon page as 'WFO (2021): Rhynchospora Vahl. Published on the Internet;http://www.worldfloraonline.org/taxon/wfo-4000033149. Accessed on: 18 Jun 2021'

General Information

Herbs, perennial or more rarely annual. Culms tufted, erect, 3-angled or terete. Leaves basal or cauline; sheath closed, with or without a ligule; leaf blade linear, flat or canaliculate. Involucral bracts leaflike, sheathing. Inflorescences paniculate, usually consisting of terminal and lateral anthelae, sometimes spicate or capitate. Spikelets sessile or pedunculate, narrowly ovoid, ovoid, or ellipsoid, slightly bilaterally compressed or terete. Glumes few to many, spirally imbricate or rarely distichous, 1-veined; basal 3 or 4 glumes shorter than apical ones and empty. Flowers bisexual or basal flower bisexual and apical one male or sterile. Perianth bristles 0-6(-13), antrorsely or retrorsely scabrous, rarely smooth. Stamens 2 or 3. Style slender; stigmas 2. Nutlet usually obovoid to ovoid, biconvex, with various ornamentations or more rarely smooth; persistent style base thickened, mostly conic or rarely lunate, spongy, base truncate or ± lobed.

  • Provided by: [I].Flora Of CHina @ efloras.org
    • Source: [
    • 5
    • ]. 

    1. Rhynchospora Vahl

    Dichromena Michaux, Psilocarya Torrey

    Por W.W. Thomas.

    Perennes o anuales vegetativamente variables. Espiguillas ovoides o lanceoloides a teretes, ocasionalmente comprimidas, con varias a muchas escamas desiguales, espiralmente arregladas, las (1-)2-varias escamas inferiores estériles. Flores en las axilas de las escamas, las 1-varias inferiores perfectas, las 1-varias superiores funcionalmente estaminadas. Estambres 1-3(-12). Cerdas hipóginas 0-6(-20). Aquenios generalmente lenticulares a globosos, con la base del estilo persistente en la punta. Estilo no dividido a profundamente partido, la base persistente generalmente triangular a deltada, ocasionalmente a manera de correa o subulada. Aprox. 250 spp. Principalmente neotropical, también en Norte y Sudamérica templadas y los trópicos del Viejo Mundo, con algunas especies en Asia y Europa templadas.

    Bibliografía: Gale, S. Rhodora 46: 89-134 (1944a); 159-197 (1944b); 207-249 (1944c), 255-278 (1944d). Guaglianone, E.R. Darwiniana 23: 255-311 (1979); 499-509 (1980); 23: 489-506 (1981). Koyama, T. Mem. New York Bot. Gard. 23: 23-89 (1972). Kükenthal, G. Bot. Jahrb. Syst. 74: 375-509 (1949); 75: 90-126 (1950a); 127-195 (1950b); 75: 273-314 (1951). Thomas, W.W. Mem. New York Bot. Gard. 37: 1-116 (1984).

  • Provided by: [G].Flora Mesoamericana
    • Source: [
    • 6
    • 1
    • ]. 


    Por Robert Kral y W. Wayt Thomas

    Perennes o anuales; culmos teretes o triangulares; plantas hermafroditas o andromonoicas. Hojas con láminas lineares, planas, dobladas o acanaladas; vaina abierta o cerrada, sin lígula. Inflorescencias foliosas o bracteado-setáceas; espiguillas fasciculadas o en corimbos compuestos, cimas o capítulos; escamas pocas a numerosas, variadamente imbricadas, 1-acostilladas, las fértiles más grandes; cerdas hasta 12, variadamente apendiculadas; estambres 2 ó 3; estilo con estigma simple, linear o coronado con 2 ramas estigmáticas lineares, subiguales, la base del estilo generalmente articulada al ápice del ovario, persistente como un tubérculo en el cuerpo del fruto. Fruto variadamente ornamentado.

    Género cosmopolita con ca 250 especies, en varios ambientes mayormente húmedos, concentrado en las regiones tropicales y subtropicales del Nuevo Mundo; 42 especies se conocen en Nicaragua y 2 adicionales se esperan encontrar.

    G. Kükenthal. Vorarbeiten zu einer monographie der Rhynchosporideae. Bot. Jahrb. Syst. 74: 375–509. 1949, 75: 90–126, 127–195. 1950, 75: 274–314. 1951; W.W. Thomas. The systematics of Rhynchospora section Dichromena. Mem. New York Bot. Gard. 37: 1–116. 1984; W.W. Thomas. A synopsis of Rhynchospora (Cyperaceae) in Mesoamerica. Brittonia 44: 14–44. 1992.

  • Provided by: [F].Flora de Nicaragua
    • Source: [
    • 7
    • ]. 

    Plants mostly perennial, sometimes annual, the culms 3-angulate or terete; spikelets oblong or fusiform, variously arranged, the scales 1-nerved, spirally imbricate; upper flowers staminate, the lower perfect; perianth of bristles, or sometimes wanting; stamens usually 3; style 2-cleft or rarely entire; achene lenticular or turgid, smooth or transversely rugose, capped by the persistent style base.

  • Provided by: [H].Flora de Panama
    • Source: [
    • 8
    • ]. 

    Plantas anuales, cespitosas; culmos 4–30 cm, puberulentos. Hojas más cortas que los culmos; lámina 0.6–2.5 mm de ancho. Infl. un capítulo congesto, con 4 – 9 espiguillas y 3 ó 4 brácteas subyacentes; brácteas foliosas,verdes. Espiguillas 3–6 × 1–3 mm, ovoides, blancas, a veces con líneas ferrugíneas. Fls. sin cerdas. Aquenios0.8–1.1 × 0.8–1.5 mm, oblatos a anchamente obovados, fuertemente rugosos, pajizos a pardo anaranjado; ros-tro 0.2–0.3 mm, triangular, a veces con las puntas redondeadas o curvadas hacia arriba.

  • Provided by: [D].Manual de Plantas de Costa Rica
    • Source: [
    • 9
    • 11
    • ]. 

    Herbs, annual or perennial, cespitose or not, often scaly-rhizomatous. Culms procumbent to erect, usually trigonous, wiry to stout. Leaves basal and cauline, polystichous, mostly 3-ranked; sheaths open apically, glabrous; ligules present or absent; blades flat, V-shaped in cross section or terete, typically keeled abaxially, margins involute or revolute, usually scabrid or scabridulous. Inflorescences terminal, rarely pseudolateral, paniculate, corymbose, anthelate, racemose, or capitate; spikelets 3–100 or more; involucral bracts 1–6, spreading or rarely the proximal erect, leaflike. Spikelets: scales spirally or distichously arranged, each subtending flower; 1 or more proximal scales empty. Flowers all bisexual or sometimes distalmost staminate; perianth absent or of 2–12(–20) bristles, usually persistent in fruit, rarely deciduous, variously barbed or plumed, shorter or longer than achene, seldom smooth; stamens 2–3; styles undivided or shallowly 2-fid, or deeply cleft into 2(–3) linear stigmatic branches; style base persistent as tubercle on fruit, usually articulate to achene apex, distinct, enlarged. Fruits achenes, borne on pedicellar joint, directly distal to compact, dilated receptacle; body various shades of brown, flattened, lenticular (biconvex), or nearly terete, smooth and lustrous or variously ridged, pitted, alveolate (honeycombed), cancellate (netted, latticed), papillate, or warty; tubercle mostly conic or variously triangular, terete or flattened and 2-edged, sometimes longitudinally sulcate, widest across base; base along narrow transverse suture, lunate, 2-lobed, or topping achenial “neck” or buttress, much narrower, as wide as, or wider than achene apex, decurrent down achene margins.

  • Provided by: [J].Flora of North America @ efloras.org
    • Source: [
    • 10
    • ]. 

    Plantas perennes o anuales; culmos foliosos. Hojas basales o caulinares, o ambas. Infl. de 1–varios capítu-los a fasciculada o paniculada; brácteas foliiformes o glumiformes. Espiguillas ovadas hasta fusiformes, convarias a muchas glumas espiraladas, desiguales. Fls. unisexuales o bisexuales (las superiores estaminadas, luegovarias bisexuales, y las 2–varias inferiores estériles), sin perianto, o con perianto de 1–8 cerdas; estambres 1–3;estilo entero o profundamente dividido, persistente como un rostro sobre el aquenio. Frs. (aquenios) lenticularesa globosos, turgentes, o con las caras cóncavas, la superficie lisa, rugosa, cancelada, o punteada.

  • Provided by: [D].Manual de Plantas de Costa Rica
    • Source: [
    • 11
    • 9
    • ]. 

    "Spikelets several to many, cymosely (or in part subumbellately) arranged in leafy-bracteate, open to congested infls, often forming 1– several dense glomerules; scales spirally imbricate, sometimes each subtending a fl, but more often the lower empty and only 1–few of the upper ones subtending fls; fls perfect or some of them staminate; perianth of (1–)6(–20) bristles, or sometimes wanting; stamens (1–)3; style bifid, its expanded base (tubercle) enlarged at maturity and persistent on the lenticular achene; our spp. mostly perennial (2 spp. annual), with ± leafy (seldom lfless), often trigonous stems and narrow, grass-like lvs with closed sheath. (Dichromena, Psilocarya) 200+, chiefly of warm regions."

  • Provided by: [E].New York Botanical Garden
    • Source: [
    • 12
    • ]. 


    About 200 species, widely distributed, especially in warm regions.

  • Provided by: [H].Flora de Panama
    • Source: [
    • 8
    • ]. 



    Gale, S. 1944. Rhynchospora sect. Eurhynchospora in Canada, the United States and the West Indies. Rhodora 46: 80–134, 159–197, 255–278. Kral, R. 1996. Supplemental notes on Rhynchospora crinipes and related species in sect. Fuscae (Cyperaceae). Sida 17: 385–411. Kükenthal, G. 1949–1951. Vorarbeiten zu einer Monographie der Rhynchosporoideae 18. Rhynchospora Vahl. Bot. Jahrb. Syst. 74: 375–509; 75: 90–115, 273–314, 451–497. Moore, A. G. 1977. A Taxonomic Investigation of Rhynchospora Sect. Longirostres Kunth. Ph.D. dissertation. Vanderbilt University. Thomas, W. W. 1984. Systematics of Rhynchospora sect. Dichromena. Mem. New York Bot. Gard. 37: 1–116.

  • Provided by: [J].Flora of North America @ efloras.org
    • Source: [
    • 10
    • ]. 

    Included Species


    Other Local Names

    Beak-rush, rhynchospore [Greek rhynchos, snout, and spora, seed]


     Information From

    • A CC0 1.0 Universal (CC0 1.0).
    MBG Floras Images
    Flora images. Missouri Botanical Garden. Accessed on Jun. 2018.
    • B Missouri Botanical Garden
    • C Missouri Botanical Garden
    Manual de Plantas de Costa Rica
    Hammel, B. E.; Grayum, M. H.; Herrera, C.; Zamora, N. Manual de Plantas de Costa Rica. Missouri Botanical Garden Press, 2003-2014
    • D Missouri Botanical Garden
    New York Botanical Garden
    Descriptions of plants should be attributed to the full citation for each individual article, chapter or book that is the source for each record, which should include the authors of original publication.
    • E Content licensed under Creative Commons Attribution-NonCommercial-ShareAlike 3.0 Unported License
    Flora de Nicaragua
    WD Stevens, CU Ulloa, A Pool and OM Montiel. Missouri Botanical Garden Press, 2001
    • F Missouri Botanical Garden
    Flora Mesoamericana
    Gerrit Davidse, Mario Sousa Sánchez, A. O. Chater, Universidad Nacional Autónoma de México. Instituto de Biología, Missouri Botanical Garden, Natural History Museum (London, England) UNAM, 1994
    • G Missouri Botanical Garden
    Flora de Panama
    Robert E. Woodson, Jr. and Robert W. Schery Annals of the Missouri Botanical Garden Vol. 67, No. 4 (1980), pp. ii-xxxiii
    • H Missouri Botanical Garden
    Flora Of CHina @ efloras.org
    'Flora of China @ eFloras (2008). Published on the Internet http://www.efloras.org/flora_page.aspx?flora_id=2 [accessed August 2016]' Missouri Botanical Garden, St. Louis, MO & Harvard University Herbaria, Cambridge, MA.
    • I Missouri Botanical Garden
    Flora of North America @ efloras.org
    'Flora of North America @ eFloras (2008). Published on the Internet http://www.efloras.org/flora_page.aspx?flora_id=1 [accessed August 2016]' Missouri Botanical Garden, St. Louis, MO & Harvard University Herbaria, Cambridge, MA.
    • J Flora of North America Association
    World Flora Online consortium
    World Flora Online Data. 2018.
    • K CC0 1.0 Universal (CC0 1.0).