Eleocharis cellulosa |
Eleocharis minima |
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Gulf Coast spikerush, Gulfcoast spikesedge |
small spikerush |
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Habit | Plants perennial; rhizomes 1–4 mm thick, soft to hard, longer internodes 3–7.5 cm, scales 5 mm, tubers absent. | Plants annual, tufted, often mat-forming, often stoloniferous, sometimes entirely vegetative; rhizomes absent. |
Culms | terete or obtusely trigonous, 30–80 cm × 1–5 mm, soft to hard, not septate-nodulose, internally spongy, transverse septa incomplete; plants never forming filiform, flaccid culms. |
erect, ascending or arching, quadrangular, sulcate, 1–13 cm × 0.1–0.3 mm, soft. |
Leaves | distal leaf sheaths persistent, membranous, apex acute to acuminate, often prolonged into a slender awn to 4 mm. |
distal leaf sheaths persistent or disintegrating, red-brown, stramineous, green, or mottled red-brown, translucent, apex narrowly acute. |
Spikelets | not proliferous, 14–54 × 3–5.6 mm; rachilla joints without winglike remnants of floral scales; proximal scale empty, amplexicaulous, 2.5–4.9 mm; floral scales 40–180, 2–3 per mm of rachilla, stramineous to pale brown, flanks sometimes minutely dotted reddish, usually with pale to dark brown, reddish, or purplish submarginal band, obovate to suborbicular, widest in middle, 3.4–4.5(–6) × 3–4.8 mm, cartilaginous, membranous toward margins, margins broadly translucent, membranous, apex rounded. |
basal spikelets often present, bisexual; often proliferous, ovoid or ellipsoid, laterally compressed when young, but terete at maturity, 2–7 × 1–2.6 mm, acute; proximal scale empty, often persistent, amplexicaulous, similar to floral scales; subproximal scale with a flower; floral scales spirodistichous (superficially appearing ± spiraled), (4–)10–28, 6–9 per mm of rachilla, pale brown, mottled red-brown to purple, ovate or elliptic, 1.3–2.1 × 0.7–1 mm, membranous, midribs green and red-brown, prominent, apex rounded to obtuse. |
Flowers | perianth bristles 6–7, medium brown to pale brown or reddish, slender, proximally slightly flattened, subequal to unequal, mostly exceeding achene, 2–3.4 mm, smooth or sometimes finely retrorsely spinulose; anthers reddish brown, 1.7–2.5 mm; styles 3-fid. |
perianth bristles 6, colorless, white, or stramineous, slightly shorter than to equaling achene, spinules retrorse, acute; stamens 3; anthers 0.4–0.5 mm; styles 3-fid. |
Achenes | brown, biconvex, obpyriform, 2.2–2.8 × 1.3–1.9 mm, markedly sculptured at 10–15X, each face with (17–)20–24 rows of isodiametric to slightly transversely elongated cells, apex narrowed to a stout, often pale, spongy region 0.8–1.1 mm wide at base, 1/2–3/4 of achene width. |
greenish or pale brown or red-brown, often clearly spotted greenish or red-brown, ellipsoid to obovoid, trigonous (or terete?), angles prominent (keeled), 0.6–0.8 × 0.4–0.5 mm, apex constricted proximal to tubercle, smooth. |
Tubercles | dark brown, lamelliform to pyramidal, 0.1–0.5 × 0.2–0.5 mm. |
red-brown, pyramidal, trigonous, 0.1–0.3 × 0.2–0.4 mm. |
Eleocharis cellulosa |
Eleocharis minima |
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Phenology | Fruiting late spring–winter. | Fruiting mid spring–fall. |
Habitat | Brackish to saline marshes, shores, ditches, mostly coastal, often abundant or dominant | Freshwater, sandy and peaty shores of lakes, muddy areas |
Elevation | 0 (Florida)–600 (Arkansas, Texas) m (0 (Florida)–2000 (Arkansas, Texas) ft) | 0–400 m (0–1300 ft) |
Distribution |
AL; AR; FL; GA; MS; NC; SC; TX; Mexico; West Indies; Central America (Nicaragua)
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FL; MD; TX; Mexico; South America; West Indies; Central America (Costa Rica, El Salvador, Guatemala, Nicaragua, Panama) |
Discussion | Eleocharis minima is most often confused with E. bicolor and E. baldwinii (see comments under 33. E. bicolor). Although floral scales in E. minima often superficially appear to be spirally disposed, in reality they are spirodistichous, ± decussate, while in E. baldwinii they are strictly distichous in one plane. The number of floral scales per millimeter is much greater in E. minima than in E. baldwinii. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Source | FNA vol. 23, p. 118. | FNA vol. 23, p. 97. |
Parent taxa | Cyperaceae > Eleocharis > subg. Limnochloa | Cyperaceae > Eleocharis > subg. Eleocharis > sect. Eleocharis > ser. Tenuissimae |
Sibling taxa | ||
Synonyms | Chaetocyperus jamesonii, Chaetocyperus polymorphus, Chaetocyperus viviparus, E. durandii, E. jamesonii, E. minima var. ambigua, E. oropuchensis, E. savannarum, E. subtilis, E. tenuissima, E. villaricensis, E. wrightiana, Isolepis ambigua | |
Name authority | Torrey: Ann. Lyceum Nat. Hist. New York 3: 298. (1836) | Kunth: Enum. Pl. 2: 139. (1837) |
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