Lemna turionifera |
Lemna |
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lenticulare turionifère, red duckweed, turion duckweed |
duckweed, lenticules |
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Roots | shorter than 15 cm, tip mostly rounded; sheath not winged. |
1 per frond. |
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Flowers | ovaries 1-ovulate, utricular scale with narrow opening at apex. |
1(–2) per frond, surrounded by small utricular, membranous scale; stamens 2, 4-locular. |
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Fruits | 0.5–0.6 mm, not winged. |
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Seeds | with 30–60 indistinct ribs, staying within fruit wall after ripening. |
1–5, longitudinally ribbed. |
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Stipes | white, small, often decaying. |
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Fronds | floating, 1 or 2–few, coherent in groups, obovate, scarcely gibbous, flat, 1–4 mm, 1–1.5 times as long as wide, margins entire; veins 3, greatest distance between lateral veins near or distal to above middle; papillae distinct on midline of upper surface (apical papilla scarcely larger than others); lower surface often red (more intensely so than on upper), coloring beginning at attachment point of root, upper surface (especially near apex) sometimes with red spots; air spaces to 0.3 mm; turions sometimes present, rootless, olive to brown, 0.8–1.6 mm diam., sinking to bottom. |
floating or submersed, 1 or 2–20 or more, coherent in groups or forming chains, lanceolate-ovate, flat or gibbous, 1–15 mm, margins entire or denticulate, upper surfaces sometimes with small conic papillae along veins (especially at node and near apex); air spaces in tissue; reproductive pouches 2, lateral, at base from which daughter fronds and flowers originate, triangular; veins 1–5(–7), originating from point in proximal part of frond (node) or if more than 3 veins present, outer ones sometimes branching distally from inner ones; scale at base of frond absent; anthocyanins sometimes present; pigment cells absent (red pigmentation present in some species); turions absent (sometimes present in L. turionifera). |
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x | = 10, 21, 22 |
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2n | = 40, 42 (G), 50, 80. |
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Lemna turionifera |
Lemna |
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Phenology | Flowering (occasional) summer. | |||||||||||||||||||||||||||||||||||||
Habitat | Mesotrophic to –eutrophic, quiet waters, in continental, temperate regions | |||||||||||||||||||||||||||||||||||||
Elevation | 0–3700 m (0–12100 ft) | |||||||||||||||||||||||||||||||||||||
Distribution |
AK; AL; AZ; CA; CO; CT; IA; ID; IL; IN; KS; MA; MI; MN; MO; MT; ND; NE; NJ; NM; NV; NY; OH; OK; OR; PA; RI; SD; TX; UT; VT; WA; WI; WV; WY; AB; BC; MB; NB; NL; NS; NT; ON; PE; QC; SK; YT; SPM; Mexico (Baja California); Eurasia
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Worldwide except arctic and antarctic regions |
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Discussion | I know of no specimens of Lemna turionifera from Maine, New HampshireSt. Pierre and Miquelon, or from New Jersey, but the species is to be expected there.. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
In Lemna the connection to the mother frond is formed by a thin white stipe at the base that falls off or decays after the frond is grown (frond of L. trisulca is narrowed at base into a green stalk persisting on frond). Species 13 (9 in the flora). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Key |
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Source | FNA vol. 22, p. 148. | FNA vol. 22, p. 146. | ||||||||||||||||||||||||||||||||||||
Parent taxa | Lemnaceae > Lemna | Lemnaceae | ||||||||||||||||||||||||||||||||||||
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Name authority | Landolt: Aquatic Botany 1: 355, fig. 4g–h. (1975) | Linnaeus: Sp. Pl. 2: 970. 1753; Gen. Pl. ed. 5; 417, (1754) | ||||||||||||||||||||||||||||||||||||
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