Eleocharis albida |
Eleocharis elongata |
|
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white spikerush |
slim spikerush |
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Habit | Plants perennial; rhizomes soft, longer internodes 2–4 cm, cortex loose, scales fugaceous, 6 mm, thinly membranous and translucent. | Plants perennial; rhizomes 1–1.5 mm thick, soft, longer internodes 2–3 cm, scales 5–14 mm, tubers absent. |
Culms | not rooting at tips, terete, 10–40 cm, soft to firm, smooth. |
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 proximally brownish or sometimes reddish, distally stramineous to green. |
distal leaf sheaths persistent or decaying, membranous, apex acute, often prolonged into translucent portion to 1 mm. |
Spikelets | ovoid to oblong-subcylindric, 4–12 × 2–3.5 mm, apex acute to rounded; proximal scale empty, clasping 1/2 of culm, like floral scales; subproximal 1 or 2 scales often empty; floral scales 20–100, 10 per mm of rachilla, entirely stramineous or sometimes red-brown, ovate, (1.5–)2–2.5 × 1.5 mm, apex broadly rounded, entire. |
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 (5–)6(–8), brown, stout, the longer equaling achene or tubercle, retrorsely spinulose; stamens 3; anthers brown, 1 mm. |
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 | falling with scales, obovoid, angles keeled, 0.8–1 × 0.7–0.8 mm, apex with short neck. |
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 | whitish to brown, mammillate to pyramidal, 0.2–0.3 × 0.3–0.35 mm, 1/3 or less as wide as achene. |
dark brown, pyramidal, 0.2–0.5 × 0.2–0.4 mm. |
Eleocharis albida |
Eleocharis elongata |
|
Phenology | Fruiting summer. | Fruiting late spring–late fall. |
Habitat | Coastal saltmarsh edges, sloughs, beaches, dune depressions, ditches | Sometimes drying ponds, lakeshores, marshes, creeks, canals, ditches |
Elevation | 0 m (0 ft) | 10–50 m (0–200 ft) |
Distribution |
AL; FL; GA; LA; MD; MS; NC; NM; SC; TX; Mexico; Bermuda
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AL; FL; NC; TX; Mexico; Central America; South America |
Discussion | In most spikelets, the bright brown stigmas contrast strikingly with the stramineous floral scales. We have not seen vouchers for H. K. Svenson’s (1937) reports of Eleocharis albida from Virginia. The collections we have seen from Maryland are from the 1800s. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Eleocharis elongata sometimes grows with E. robbinsii; no intermediates are known. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 23, p. 99. | FNA vol. 23, p. 117. |
Parent taxa | Cyperaceae > Eleocharis > subg. Eleocharis > sect. Eleocharis > ser. Albidae | Cyperaceae > Eleocharis > subg. Limnochloa |
Sibling taxa | ||
Name authority | Torrey: Ann. Lyceum Nat. Hist. New York. 3: 304. (1836) | Chapman: Fl. South. U.S., 515. (1860) |
Web links |