Ageratum conyzoides (L.) L.
  • Sp. Pl.
  • Mentrasto


Cite taxon page as 'WFO (2020): Ageratum conyzoides (L.) L. Published on the Internet;http://www.worldfloraonline.org/taxon/wfo-0000014938. Accessed on: 19 Sep 2020'

General Information

Herbs, annual, 50-100 cm tall, sometimes less than 10 cm, with inconspicuous main root. Stems robust, ca. 4 cm in diam. at base, simple or branched from middle, stems and branches reddish, or green toward apex, white powdery puberulent or densely spreading long tomentose. Leaves often with axillary abortive buds; petiole 1-3 cm, densely white spreading villous; median leaves ovate, elliptic, or oblong, 3-8 × 2-5 cm; upper leaves gradually smaller, oblong, sometimes all leaves small, ca. 1 × 0.6 cm, both surfaces sparsely white puberulent and yellow gland-dotted, basally 3-veined or obscurely 5-veined, base obtuse or broadly cuneate, margin crenate-serrate, apex acute. Capitula small, 4-14, in dense terminal corymbs; peduncle 0.5-1.5 cm, powdery puberulent; involucre campanulate or hemispheric, ca. 5 mm in diam.; phyllaries 2-seriate, oblong or lanceolate-oblong, 3-4 mm, glabrous, margin lacerate; corollas 1.5-2.5 mm, glabrous or apically powdery puberulent; limb purplish, 5-lobed. Achenes black, 5-angled, 1.2-1.7 mm, sparsely white setuliferous; pappus scales 5 or awned, 1.5-3 mm. Fl. and fr. year-round. 2n = 20, 38, 40.

  • Provided by: [G].Flora Of CHina @ efloras.org
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    Annuals, perennials, or sub-shrubs, 20–150 cm (fibrous-rooted). Stems erect, sparsely to densely villous. Leaf blades ovate to elliptic-oblong, 2–8 × 1–5 cm, margins toothed, abaxial faces sparsely pilose and gland-dotted. Peduncles minutely puberulent and sparsely to densely pilose, eglandular. Involucres 3–3.5 × 4–5 mm. Phyllaries oblong-lanceolate (0.8–1.2 mm wide), glabrous or sparsely pilose (margins often ciliate), eglandular, tips abruptly tapering, subulate, 0.5–1 mm. Corollas usually blue to lavender, sometimes white. Cypselae sparsely strigoso-hispidulous; pappi usually of scales 0.5–1.5(–3) mm, sometimes with tapering setae, rarely 0. 2n = 20, 40.

  • Provided by: [K].Flora of North America @ efloras.org
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    Ageratum conyzoides L., Sp. Pl. 839. 1753; A. microcarpum (Benth.) Hemsl.; Alomia microcarpa (Benth.) B.L. Rob.

    Hierbas erectas y anuales o procumbentes y perennes, mayormente 0.3–1 m de alto; tallos enraizando en los nudos, variadamente pilosos, pubérulos o casi glabros. Hojas ampliamente ovadas a cordadas, 2–12 cm de largo y 1–5 cm de ancho, márgenes aserrado-crenados, pubescentes, 3-nervias desde la base; pecíolos 1–4 cm de largo. Capitulescencias subumbeladas a cimoso-paniculadas; involucros 3.5–4.5 mm de largo; filarias en 2–3 series, lanceoladas, subiguales, agudas, 2–3-nervias, variadamente pubescentes a glabras; flósculos ca 50, las corolas azules a purpúreas, raramente blancas, el tubo ca 1 mm de largo, glanduloso, el limbo infundibuliforme, 1.5–2 mm de largo, los lobos pubescentes. Aquenios 1.1–1.3 mm de largo, glabros o setíferos, negros; vilano de escamas lanceoladas, 2–3.5 mm de largo, aristadas o raramente una corona escamosa o ausente.

    Maleza abundante en ambientes alterados en todo el país; 0–1200 m; fl y fr mayormente dic–jun; Araquistain 1673, Sandino 1033; América tropical, ampliamente introducida en otros sitios. Fue tratada como A. microcarpum en la Flora of Panama, pero estoy de acuerdo en reducir este nombre bajo el presente taxón como lo fue hecho en la Flora of Guatemala. Las formas sin vilano de A. conyzoides no son comunes en Nicaragua (Araquistain 1768, Moreno 6986, 7048) y no difieren significativamente de lo que yo he denominado A. conyzoides. Johnson reconoce 2 subespecies: A. conyzoides ssp. conyzoides y A. conyzoides ssp. latifolium (Cav.) M.F. Johnson. Nuestro material pertenece predominantemente a la subespecie típica, estando la otra subespecie principalmente restringida al noroeste de Sudamérica.

  • Provided by: [E].Flora de Nicaragua
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    Annual or short-lived perennial erect herbs or subshrubs to 1.5 m tall, sparingly branched; stems becoming brownish to slightly reddish, terete, slightly striate, usually fistulose, sparsely to densely long-pilose, usually also slightly puberulous. Leaves mostly opposite; blades ovate to broadly ovate, to 10 cm long and 7 cm wide, the base rounded to cuneate, strongly trinervate from the base, the margins usually crenate, the apex short-acute to narrowly rounded or obtuse, the upper sur- face dull green, sparsely long-pilose, the lower surface slightly paler green, promi- nently glandular-punctate, sparsely pilose on the veins and veinlets; petioles to 2.5 mm long. Inflorescence cymose to subcymose with compact corymbose to sub- umbellate branches, the branches somewhat densely puberulous with few to many longer hairs, the ultimate branches 3-10 mm long, often slightly enlarged distally. Heads ca. 4.0-4.5 mm high with ca. 50 florets; involucral bracts 25-30, eximbricate, in 2 series, mostly 3-4 mm long, oblong-lanceolate, prominently bicostate, with prominent antrorsely angular or lacerate scarious margins, the apex shortly to very sharply acute, usually not scarious near tip, the outer surface with usually few long hairs; receptacle naked; corolla white or blue, ca. 1.7 mm long, narrowly funnelform, with few hairs on the outer surface, the tube narrow, ca. 1 mm long, with scattered small short-stalked glands, the lobes 0.2-0.3 mm long, with papillae moderately developed inside, at tip and on margins, 1-2 hairs on outer surface; style branches extremely slender, sometimes short, with crowded blunt papillae

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    forming nearly 1/2 the width. Achenes ca. 1.2 mm long, with sparse short bristles usually restricted to the ribs; carpopodium asymmetrical; pappus of 5 large free scales, the scales usually lanceolate with long slender awns, to 2 mm long with awns.

  • Provided by: [D].Flora de Panama
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    Morphology

    A common weed.

  • Provided by: [I].Plants Of the World Online Portal - FWTA
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    Mauve florets in heads about 1/4 in. long

  • Provided by: [I].Plants Of the World Online Portal - FWTA
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    A faintly aromatic erect or procumbent annual herb 1-3 ft. high

  • Provided by: [I].Plants Of the World Online Portal - FWTA
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    Inflorescence much branched, open, of 1–several bunches of ± 7–40 heads borne in open to dense cymose clusters on pubescent and pilose bracteolate peduncles; capitula 4–5 mm in diameter; stalks of individual capitula 2–12 mm, extending in fruit to 37 mm; phyllaries bi-seriate, green, ovate to oblong-lanceolate, usually 2-ribbed, outer series 3.5–4.5 mm long, 0.9–1 mm wide, inner slightly narrower, margins basally entire, erose to lacerate at apex, rarely entire, apex abruptly contracted to point, occasionally short-acuminate, often purple, glabrous to subglabrous to very sparesly pilose.

  • Provided by: [J].Plants Of the World Online Portal - FTEA
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    Florets 40–57, corolla tubular to sub-urceolate, 2–2.2 mm long, tube white, limb externally glabrous to sub-glabrous, lobes acute, blue, white, mauve, or purple; anthers basally rounded; style-arms blue, white, mauve or purple, exserted for 0.8–1.2 mm, papillate.

  • Provided by: [J].Plants Of the World Online Portal - FTEA
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    Annual herb to 1 m tall, malodorous; stem erect to occasionally decumbent, terete, sparsely pilose and whitish pubescent, especially at nodes, to subglabrous.

  • Provided by: [J].Plants Of the World Online Portal - FTEA
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    Leaves opposite to occasionally sub-opposite above, with pubescent petiole 0.3–3 cm, blade ovate to rhomboid, 2.2–8.5 cm long, 1.2–6 cm wide, base obtuse, margins crenate to serrate, apex acute or obtuse, upper surface subglabrous to sparsely pilose, lower surface moderately pilose.

  • Provided by: [J].Plants Of the World Online Portal - FTEA
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    Achenes 1.2–1.8 mm long, glabrous between ribs; pappus of 5 triangular scales 1.9–2 mm long, acuminate into a slender awn (see note), margins scabrid.

  • Provided by: [J].Plants Of the World Online Portal - FTEA
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    Fig. 181/1–8 (page 828).

  • Provided by: [J].Plants Of the World Online Portal - FTEA
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    Annual herb, up to 1 m high. Leaves opposite. Heads 4-5 mm across. Involucral bracts oblong, abruptly acuminate, erose, sparsely if at all hairy on back, hairs eglandular. Flowers purplish, bluish or white.

  • Provided by: [H].e-Flora of South Africa
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    Habit

    herbs or subshrubs

  • Provided by: [D].Flora de Panama
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    Habitat

    Weed of cultivation, often near water.

  • Provided by: [H].e-Flora of South Africa
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    Weedy escape in cultivation and post-cultivation, often a pioneer on cleared land such as logging tracks, also in grassland and Acacia woodland.

  • Provided by: [H].e-Flora of South Africa
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    Distribution

    native in Central and South America and has become widely adventive in most tropical and many subtropical parts of the world.

  • Provided by: [D].Flora de Panama
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    Native to the West Indies, Mexico, Central and South America.

  • Provided by: [H].e-Flora of South Africa
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    Distribution Map

     
    • Native distribution
    Found in
    • Southern America Brazil Acre
    • Amapí
    • Amazonas
    • Parí
    • Rondônia
    • Roraima
    • Tocantins
    • Alagoas
    • Bahia
    • Ceará
    • Maranh
    • Paraába
    • Pernambuco
    • Piauá
    • Rio Grande do Norte
    • Sergipe
    • Paraní
    • Rio Grande do Sul
    • Santa Catarina
    • Espirito Santo
    • Minas Gerais
    • Rio de Janeiro
    • São Paulo
    • Brazilia Distrito Federal
    • Goiás
    • Mato Grosso
    • Mato Grosso do Sul

    Synonyms

    Other Local Names

    NameLanguageCountry
    MentrastoPortuguese

      Bibliography

     Information From

    Compositae
    CC0 1.0 Universal (CC0 1.0). https://creativecommons.org/publicdomain/zero/1.0
    • A CC0 1.0 Universal (CC0 1.0).
    MBG Floras Images
    http://www.tropicos.org/ImageSearch.aspx
    Flora images. Missouri Botanical Garden. Accessed on Jun. 2018.
    • B Missouri Botanical Garden
    • C Missouri Botanical Garden
    Flora de Panama
    http://www.tropicos.org/Project/PAC
    Robert E. Woodson, Jr. and Robert W. Schery Annals of the Missouri Botanical Garden Vol. 67, No. 4 (1980), pp. ii-xxxiii
    • D Missouri Botanical Garden
    Flora de Nicaragua
    http://www.tropicos.org/projectwebportal.aspx?projectid=7&pagename=Home&langid=66
    WD Stevens, CU Ulloa, A Pool and OM Montiel. Missouri Botanical Garden Press, 2001
    • E Missouri Botanical Garden
    Brazilian Flora 2020 project - Projeto Flora do Brasil 2020
    http://floradobrasil.jbrj.gov.br
    Brazil Flora G (2014): Brazilian Flora 2020 project - Projeto Flora do Brasil 2020. v393.147. Instituto de Pesquisas Jardim Botanico do Rio de Janeiro. Dataset/Checklist. doi:10.15468/1mtkaw
    • F Group Brazil Flora, REFLORA Program
    Flora Of CHina @ efloras.org
    http://www.efloras.org/flora_page.aspx?flora_id=2
    '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.
    • G Missouri Botanical Garden
    e-Flora of South Africa
    e-Flora of South Africa. v1.21. 2018. South African National Biodiversity Institute. http://ipt.sanbi.org.za/iptsanbi/resource?r=flora_descriptions&v=1.21
    • H All Rights Reserved
    Plants Of the World Online Portal - FWTA
    https://www.kew.org/science/who-we-are-and-what-we-do/strategic-outputs-2020/plants-of-the-world-online
    http://www.plantsoftheworldonline.org/terms-and-conditions
    • I The Trustees of the Royal Botanic Gardens, Kew
    Plants Of the World Online Portal - FTEA
    https://www.kew.org/science/who-we-are-and-what-we-do/strategic-outputs-2020/plants-of-the-world-online
    http://www.plantsoftheworldonline.org/terms-and-conditions
    • J
    Flora of North America @ efloras.org
    http://www.efloras.org/flora_page.aspx?flora_id=1
    '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.
    • K Flora of North America Association
    World Flora Online consortium
    http://www.worldfloraonline.org/organisation/WFO
    World Flora Online Data. 2018.
    • L CC0 1.0 Universal (CC0 1.0).