Eleocharis bella |
Eleocharis aestuum |
|
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beautiful spikerush, delicate spikerush, pretty spikerush |
tidal spikerush, tidal spikesedge |
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Habit | Plants annual, rarely perennial, usually densely tufted; rhizomes rarely evident, 0.2–0.3 mm thick, internodes 1–5 mm, scales not evident. | |
Culms | often ascending or spreading, 4-angled or sometimes terete, sometimes sulcate, 1–7 cm × 0.2–0.3 mm, soft to firm. |
often spreading or declining, 3–30 cm × 0.5–1 mm. |
Leaves | sheaths stramineous, distal sheaths often splitting abaxially, slightly inflated distally, oblique, apex acute. |
apex of distal leaf sheath obtuse, tooth to 0.2(–0.5) mm. |
Spikelets | ovoid, 1.5–4 × 0.8–2 mm, apex acute; floral scales 4–15, 8 per mm of rachilla, colorless or reddish brown, midrib region green, ovate-lanceolate, not folded lengthwise, 1–1.5 × 0.5–0.7 mm, mibrib obscure to somewhat keeled, apex narrowly acute to acuminate, slightly recurved. |
ellipsoid to ovoid, 3–10 × 2–4 mm, apex blunt to subacute; floral scales 10–100+, 10 per mm of rachilla, colorless to pale brownish except for green midrib, 1.5–2 × 1 mm, midribs not keeled, apex rounded. |
Flowers | perianth bristles absent; anthers 0.3–0.5 mm. |
perianth bristles absent or 2–4, stramineous or whitish, shorter than to nearly 1/2 achene, very slender, without spinules; stamens 2(–3); anthers 0.3–0.5 mm; styles 2-fid or some 3-fid. |
Achenes | with angles and longitudinal ridges ca. 6–10, rather prominent, broadly ovoid, less than 2 times longer then wide, (0.55–)0.65–0.75 × 0.3–0.4 mm, apex blunt, trabeculae distinct, 20–30. |
0.75–1 × 0.6–0.8 mm. |
Tubercles | grayish, mostly appressed, pyramidal, often depressed, 0.1–0.2 × 0.1–0.25 mm. |
deltoid, 0.2–0.3 × 0.35–0.45(–0.55) mm, 1/2–3/4as high as wide, 1/4–1/3 as high and 1/2–2/3(–4/5) as wide as achene. |
Eleocharis bella |
Eleocharis aestuum |
|
Phenology | Fruiting spring–summer. | Fruiting summer–fall (Jul–Oct). |
Habitat | Bare, often drying soil of stream alluvium, lake margins, wet meadows | Fresh tidal river shores |
Elevation | 200–2900 m (700–9500 ft) | 0–10 m (0–0 ft) |
Distribution |
AZ; CA; ID; MT; NM; NV; OR; WA; Mexico (Chihuahua)
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CT; DE; MA; ME; NJ; NY; PA |
Discussion | Eleocharis bella and E. acicularis seem to be amply distinct; putative hybrids are unknown. The occasional plants of E. bella with evident rhizomes, which include the type, are otherwise identical to plants apparently without rhizomes. Eleocharis bella is very similar to E. cancellata. There is an Illinois collection from Peoria in 1901, from the alluvial banks of the Illinois River. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Eleocharis aestuum is very similar to E. diandra and E. ovata; E. diandra differs from E. aestuum in its lower tubercles, brown floral scales, and absence of perianth bristles; E. ovata differs as given in the key to species. D. M. Hines (1975) described E. aestuum using the epithet “palidostachys” [ined.]. Specimens from shores of the Lake-of-the-Woods in Minnesota, and a reservoir and farm in Hardin and Fayette counties, Tennessee, may be referable to E. aestuum. The only recent records of E. aestuum are from the Androscoggin and Kennebec rivers in Maine and the Hudson River in New York (A. Haines 2001). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 23, p. 110. | FNA vol. 23, p. 104. |
Parent taxa | Cyperaceae > Eleocharis > subg. Scirpidium | Cyperaceae > Eleocharis > subg. Eleocharis > sect. Eleogenus > ser. Ovatae |
Sibling taxa | ||
Synonyms | E. acicularis var. bella, E. acicularis var. minima | |
Name authority | (Piper) Svenson: Rhodora 31: 201. (1929) | Hines ex A. Haines: Novon 11: 45. (2001) |
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