Eleocharis bella |
Eleocharis parishii |
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beautiful spikerush, delicate spikerush, pretty spikerush |
Parish spikerush, Parish's spike rush |
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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. | Plants perennial, mat-forming; rhizomes evident, long, 0.5–1(–2) mm thick, firm, cortex persistent, longer internodes 5–30 mm, scales often fugaceous, 5–10 mm, membranous, not fibrous. |
Culms | often ascending or spreading, 4-angled or sometimes terete, sometimes sulcate, 1–7 cm × 0.2–0.3 mm, soft to firm. |
terete or cross section elliptic (or rectangular), usually with to 8 blunt ridges when dry, 10–50 cm × 0.2–0.7(–1) mm, soft to firm, spongy. |
Leaves | sheaths stramineous, distal sheaths often splitting abaxially, slightly inflated distally, oblique, apex acute. |
distal leaf sheaths persistent, not splitting, mostly proximally dark red, distally red to brown or green, thinly papery to thickly membranous, apex usually redbrown, subtruncate to obtuse or subacute, callose, tooth often present on most or all culms, to 1 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. |
narrowly lanceoloid (to narrowly cylindric), 3–20 × 1.5–2.5 mm, apex acute; proximal scale amplexicaulous, entire; subproximal scale empty or with flower; floral scales appressed or spreading in fruit, 15–40, 3–4 per mm of rachilla, orange brown, midrib regions often greenish, ovate, 2–3 × 1 mm, apex entire, rounded to obtuse in proximal part of spikelet, acute in distal part, carinate, at least in distal part of spikelet. |
Flowers | perianth bristles absent; anthers 0.3–0.5 mm. |
perianth bristles 3–7, rarely apparently absent, stramineous to whitish, slender to stout, often unequal, rudimentary to slightly exceeding tubercle; stamens 3; anthers yellow to stramineous, 1.1–2 mm; styles 3-fid, 0.3–0.4 × 0.2–0.3 mm. |
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. |
falling with scales, yellow-brown or dark brown, ellipsoid or obovoid to obpyriform, compressed-trigonous, angles evident to obscure, rarely prominent, 0.8–1.4 × 0.5–0.7 mm, neck absent to long, smooth or sometimes minutely cancellate at 20–30X. |
Tubercles | grayish, mostly appressed, pyramidal, often depressed, 0.1–0.2 × 0.1–0.25 mm. |
whitish, pyramidal, often higher than wide, 0.3–0.4 × 0.25–0.35 mm. |
2n | = 10. |
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Eleocharis bella |
Eleocharis parishii |
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Phenology | Fruiting spring–summer. | Fruiting spring–fall. |
Habitat | Bare, often drying soil of stream alluvium, lake margins, wet meadows | Fresh to brackish, wet soil or emergent, often drying lakeshores, ponds, streams, springs |
Elevation | 200–2900 m (700–9500 ft) | 500–2300 m (1600–7500 ft) |
Distribution |
AZ; CA; ID; MT; NM; NV; OR; WA; Mexico (Chihuahua)
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AZ; CA; KS; NM; NV; OR; TX; UT; Mexico
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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 parishii is very similar to E. montevidensis, with which it sometimes grows. It differs from E. montevidensis mainly in its narrowly lanceoloid to cylindric spikelets and its floral scale apices not recurved or horizontally wrinkled. Some apparent intermediates occur in regions of sympatry. The floral scales of E. montevidensis are more densely placed on the rachilla. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 23, p. 110. | FNA vol. 23, p. 80. |
Parent taxa | Cyperaceae > Eleocharis > subg. Scirpidium | Cyperaceae > Eleocharis > subg. Eleocharis > sect. Eleocharis > ser. Eleocharis |
Sibling taxa | ||
Synonyms | E. acicularis var. bella, E. acicularis var. minima | E. disciformis, E. montevidensis var. disciformis, E. montevidensis var. parishii |
Name authority | (Piper) Svenson: Rhodora 31: 201. (1929) | Britton: J. New York Microscop. Soc. 5: 110. (1889) |
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