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
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.