Ambrosia Linnaeus (Q2718)

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Ambrosia is a taxon with the rank genus within the tribe Heliantheae
Language Label Description Also known as
English
Ambrosia Linnaeus
Ambrosia is a taxon with the rank genus within the tribe Heliantheae

    Statements

    taxon/id/Ambrosia Linnaeus
    0 references
    Ambrosia Linnaeus
    Ambrosia
    Linnaeus
    FNA Editorial Committee. 2006. Flora of North America north of Mexico. Volume 21: Magnoliophyta: Asteridae, part 8: Asteraceae, part 3. Oxford University Press, New York.
    accepted
    Ragweed (English)
    Tropical to subtropical and temperate New World
    mostly North America
    some established in Old World
    Annuals, perennials, or shrubs, 10–400+ cm (usually rhizomatous).
    Stems erect, decumbent, or prostrate, branched.
    Leaves usually cauline;
    sessile or petiolate;
    blades (or lobes) deltate, elliptic, filiform, lanceolate, linear, obovate, ovate, or rhombic (and most intermediate shapes), usually pinnately, sometimes palmately lobed, ultimate margins entire or toothed, faces hairy or glabrate, usually glanddotted or stipitate-glandular.
    Heads discoid (unisexual, pistillate proximal to or intermixed with staminates, staminates usually in racemiform to spiciform arrays; rarely, single plants all or mostly staminate or pistillate).
    Pistillate heads: phyllaries 12–30 (–80+) in 1–8+ series, outer (1–) 5–8 distinct or ± connate, herbaceous, the rest (sometimes interpreted as paleae) ± connate, usually with free tips forming tubercles, spines, or wings (the whole becoming a hard perigynium or “bur”);
    florets 1 (–5+), corollas 0.
    Staminate heads: involucres cupshaped to saucer-shaped, 1.5–6+ mm diam.;
    phyllaries 5–16+ in ± 1 series, ± connate;
    receptacles ± flat or convex;
    paleae spatulate to linear, membranous, sometimes villous, hirtellous, and/or glanddotted or stipitate-glandular, sometimes none;
    corollas whitish or purplish, ± funnelform, lobes 5, erect or incurved;
    staminal filaments connate, anthers distinct or weakly coherent.
    Cypselae (black) ± ovoid or fusiform, enclosed within globose to obovoid, pyramidal, pyriform, obconic, or fusiform, hard, smooth, tuberculate, spiny, or winged “burs”;