genusNajas

Najas minor

Allioni

Flora Pedemontana 2: 221. 1785.

WeedyIntroduced
Treatment appears in FNA Volume 22.

Stems profusely branched near apex distally, 11–120 cm × 0.2–1 mm; internodes 0.5–5.8 cm, without prickles abaxially. Leaves usually recurved with age, 0.5–3.4 cm, stiff in age; sheath 1–3 mm wide, apex truncate to auriculate; blade 0.1–1.2 mm wide, margins conspicuously serrulate, teeth 7–15 per side, apex acute, with 1–2 teeth, teeth multicellular; midvein without prickles abaxially. Flowers 1–2 per axil, staminate and pistillate on same plant. Staminate flowers in distal axils, 1.9–2.2 mm; involucre 2-lobed, beaks 0.4–2.1 mm; anther 1-loculed, 0.3 mm.


Phenology: Flowering summer–fall.
Habitat: Ponds, lakes, and slow- moving streams
Elevation: 0–500 m

Distribution

V22 267-distribution-map.jpg

Introduced; Ala., Del., Fla., Ga., Ill., Ind., Ky., La., Mass., Mich., Miss., Mo., N.Y., N.C., Ohio, Okla., Pa., S.C., Tenn., Vt., Va., W.Va., Eurasia, Africa

Discussion

Pistillate flowers in distal to proximal axils, 2.2 mm; styles 1–1.2 mm; stigmas 2-lobed. Seeds slightly recurved, purplish, fusiform, 1.5–3 × 0.5–0.7 mm, apex with style situated at center; testa dull, 3 cell layers thick, pitted; aeroleareoles regularly arranged in ca. 15 longitudinal rows, ladderlike, 4-angled, broader than long, end walls not raised. 2n = 24.

Najas minor, with its mature leaves recurved and with its aeroleareoles broader than long and arranged in longitudinal rows like the rungs of a ladder, is one of the more distinctive species of Najas. Young sterile individuals resemble N. gracillima, however.

Selected References

None.

Lower Taxa

None.

"elongating" is not a number.

... more about "Najas minor"
0.3 cm3 mm <br />0.003 m <br /> (?) +
acute +, truncate +  and auriculate +
Robert R. Haynes +
Allioni +
0.04 cm0.4 mm <br />4.0e-4 m <br /> (0.21 cm2.1 mm <br />0.0021 m <br />) +
armed +  and 1-veined +
0.01 cm0.1 mm <br />1.0e-4 m <br /> (0.12 cm1.2 mm <br />0.0012 m <br />) +
in 15-60 longitudinal rows +  and arranged +
sharp-tipped +
short-pedunculate +  and sessile +
Ala. +, Del. +, Fla. +, Ga. +, Ill. +, Ind. +, Ky. +, La. +, Mass. +, Mich. +, Miss. +, Mo. +, N.Y. +, N.C. +, Ohio +, Okla. +, Pa. +, S.C. +, Tenn. +, Vt. +, Va. +, W.Va. +, Eurasia +  and Africa +
0–500 m +
staminate +  and pistillate +
1 +  and 2 +
0.19 cm1.9 mm <br />0.0019 m <br /> (0.22 cm2.2 mm <br />0.0022 m <br />) +
Ponds, lakes, and slow- moving streams +
0.5 cm5 mm <br />0.005 m <br /> (5.8 cm58 mm <br />0.058 m <br />) +
light green +  and brown +
red-purple +  and purple +
whorled +, appearing +  and opposite +
submersed +
0.5 cm5 mm <br />0.005 m <br /> (3.4 cm34 mm <br />0.034 m <br />) +
serrate to minutely +
Flowering summer–fall. +
not stipitate +
Flora Pedemontana +
15 +  and 60 +
auriculate +  and not auriculate +
fusiform +  and obovoid +
not persisting +
variously--shaped +
Weedy +  and Introduced +
11 cm110 mm <br />0.11 m <br /> (120 cm1,200 mm <br />1.2 m <br />) +
slender +
0.2mm;1mm +
2-4-branched +
Najas minor +
species +
10 +  and 15 +
multicellular +
caulescent +  and not rhizomatous +
perennial +  and annual +