Eleocharis elongata

Copyright: Flora of North America Association

Plants perennial; rhizomes 1–1.5 mm thick, soft, longer internodes 2–3 cm, scales 5–14 mm, tubers absent. Culms obscurely trigonous to terete; spikelet-bearing culms 16–80 cm × 0.5–1.5 mm; when submersed plants often forming numerous, filiform flaccid culms without spikelets, sometimes with whorls of slender branches, 0.1–0.3 mm wide, soft; sometimes septate-nodulose when aquatic, internally spongy, transverse septa incomplete. Leaves: distal leaf-sheaths persistent or decaying, membranous, apex acute, often prolonged into translucent portion to 1 mm. Spikelets not proliferous, (6–) 9–24 × 1.4–2.2 mm; rachilla joints bearing prominent winglike remnants of floral scales; proximal scale with a flower, amplexicaulous, 2.5–4.1 mm; floral scales 7–26, 1–2 per mm of rachilla, green to stramineous or pale-brown, often minutely dotted reddish, usually with conspicuous dark-brown to blackish submarginal band, narrowly ovate, 3.5–4.5 × 2 mm, thickly papery, membranous toward margins. Flowers: perianth bristles 6–7, whitish to stramineous or pale reddish-brown, proximally slightly flattened, unequal, exceeding or rarely shorter than achene, 0.7–1.9 mm, retrorsely spinulose; anthers yellow to reddish, 1.7–1.9 mm; styles 3-fid. Achenes whitish, stramineous, or pale green, obovoid to obpyriform, compressed trigonous with adaxial face broadest, or biconvex, 0.65–1.4 × 0.5–0.8 mm, clearly sculptured at 10–15X, each face with 10–13 rows of rectangular, transversely elongated cells, apex constricted to short neck 0.2–0.25 (–0.3) mm wide, wider at tubercle base. Tubercles dark-brown, pyramidal, 0.2–0.5 × 0.2–0.4 mm.

Phenology: Fruiting late spring–late fall.
Habitat: Sometimes drying ponds, lakeshores, marshes, creeks, canals, ditches
Elevation: 10–50 m

Ala., Fla., N.C., Tex., Mexico, Central America, South America

Discussion

Eleocharis elongata sometimes grows with E. robbinsii; no intermediates are known.

Selected References

None.

Lower Taxa