Lemna turionifera |
Lemna perpusilla |
|
---|---|---|
lenticulare turionifère, red duckweed, turion duckweed |
lenticule très petite, minute duckweed |
|
Roots | shorter than 15 cm, tip mostly rounded; sheath not winged. |
to 3.5 cm, tip usually sharp pointed; sheath narrowly winged at base (wing 2–3 times as long as wide). |
Flowers | ovaries 1-ovulate, utricular scale with narrow opening at apex. |
ovaries 1-ovulate, utricular scale open on 1 side. |
Fruits | 0.5–0.6 mm, not winged. |
0.7–1 mm, not winged. |
Seeds | with 30–60 indistinct ribs, staying within fruit wall after ripening. |
with 35–70 indistinct ribs, staying within fruit wall after ripening. |
Stipes | white, small, often decaying. |
white, small, often decaying. |
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, 1 or 2–few, coherent in groups, ovate-obovate, flat, 1–4 mm, 1–1.7 times as long as wide, margins entire; veins 3, greatest distance between lateral veins near or distal to middle; 1 distinct papilla near apex on upper surface, 2–3 very distinct papillae above node; anthocyanin absent, no reddish color; air spaces much shorter than 0.3 mm; distinct turions absent. |
2n | = 40, 42 (G), 50, 80. |
= 40 (U), 42 (G). |
Lemna turionifera |
Lemna perpusilla |
|
Phenology | Flowering (occasional) summer. | Flowering (frequent) late spring–fall. |
Habitat | Mesotrophic to –eutrophic, quiet waters, in continental, temperate regions | Mesotrophic to eutrophic, quiet waters in temperate regions with relatively mild winters |
Elevation | 0–3700 m (0–12100 ft) | 0–600 m (0–2000 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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AR; CT; DC; DE; IA; IL; IN; KS; KY; MA; MD; ME; MN; MO; NC; NE; NJ; NY; OH; OK; PA; RI; TN; TX; VA; VT; WI; WV; QC
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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.) |
I know of no specimens of Lemna perpusilla from Connecticut or New Hampshire. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 22, p. 148. | FNA vol. 22, p. 149. |
Parent taxa | Lemnaceae > Lemna | Lemnaceae > Lemna |
Sibling taxa | ||
Name authority | Landolt: Aquatic Botany 1: 355, fig. 4g–h. (1975) | Torrey: Fl. New York 2: 245. (1843) |
Web links |
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