The green links below add additional plants to the comparison table. Blue links lead to other Web sites.
enable glossary links

little duckweed

least duckweed

Roots

to 15 cm, tip mostly rounded;

sheath not winged.

to 1.5 cm, tip rounded to pointed;

sheath not winged.

Flowers

ovaries 1-ovulate, utricular scale with narrow opening at apex.

ovaries 1-ovulate, utricular scale open on 1 side.

Fruits

0.5–0.7 mm, not winged.

0.6–1 mm, not winged.

Seeds

with 10–16 distinct ribs, staying within fruit wall after ripening.

with 12–15 distinct ribs.

Stipes

white, small, often decaying.

white, small, often decaying.

Fronds

floating, 1 or 2–5 or more, coherent in groups, obovate, flat or gibbous, 1–3.5 mm, 1–1.5 times as long as wide, margins entire;

veins 3, greatest distance between lateral veins near middle;

very distinct papillae near apex, some smaller indistinct ones on midline of upper surface;

lower surface very often red colored (more intensely than on upper), coloring beginning at attachment point of root, lower upper surface sometimes with red spots;

air spaces shorter than 0.3 mm; distinct turions absent.

floating, 1 or 2–few, coherent in groups, obovate, flat to thickish (but not gibbous), 0.8–4 mm, 1–2 times as long as wide, margins entire;

veins 1, sometimes indistinct, very rarely longer than extension of air spaces, not longer than 2/3 of distance between node and apex;

with or without small papillae along midline;

anthocyanin absent;

largest air spaces much shorter than 0.3 mm;

turions absent.

2n

= 40, 42, 50.

= 36 (U), 40 (U), 42 (G).

Lemna obscura

Lemna minuta

Phenology Flowering (occasional) spring–fall. Flowering (very rare) late spring–early fall.
Habitat Mesotrophic to –eutrophic, quiet waters, in temperate to subtropical regions with mild winters Mesotrophic to eutrophic, quiet waters in temperate to subtropical regions with relatively mild winters
Elevation 0–800 m (0–2600 ft) 0–2600 m (0–8500 ft)
Distribution
from FNA
AL; AR; DC; DE; FL; GA; IA; IL; IN; KS; KY; LA; MD; MN; MO; MS; NC; NE; NJ; NY; OH; OK; PA; SC; SD; TN; TX; VA; WI; c Mexico; South America (Colombia, Ecuador); Hawaii
[WildflowerSearch map]
[BONAP county map]
from FNA
AL; AR; AZ; CA; CO; FL; GA; IL; IN; KS; KY; LA; MI; MO; NE; NM; NV; OH; OK; OR; TN; TX; UT; WA; WV; WY; Mexico; Central America; South America; West Indies [Introduced, Eurasia (introduced)]
[WildflowerSearch map]
[BONAP county map]
Discussion

I know of no specimens of Lemna minuta from Mississippi, but the species is to be expected there.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Source FNA vol. 22. FNA vol. 22, p. 150.
Parent taxa Lemnaceae > Lemna Lemnaceae > Lemna
Sibling taxa
L. aequinoctialis, L. gibba, L. minor, L. minuta, L. perpusilla, L. trisulca, L. turionifera, L. valdiviana
L. aequinoctialis, L. gibba, L. minor, L. obscura, L. perpusilla, L. trisulca, L. turionifera, L. valdiviana
Synonyms L. minor var. obscura L. minima, L. minuscula
Name authority (Austin) Daubs: Illinois Biological Monographs 34: 20. (1965) Kunth: in A. von Humboldt et al., Nov. Gen. Sp. 1: 372. (1816)
Web links