Eleocharis bella |
Eleocharis suksdorfiana |
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beautiful spikerush, delicate spikerush, pretty spikerush |
Suksdorf spikerush, Suksdorf'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; rhizomes 0.5–1.5 mm thick, scales persistent, 5–10 mm, thinly membranous, not fibrous; resting buds absent (non-resting buds on rhizome apex ellipsoid, 10 × 2–5 mm); caudices present, hard, 2 mm thick. |
Culms | often ascending or spreading, 4-angled or sometimes terete, sometimes sulcate, 1–7 cm × 0.2–0.3 mm, soft to firm. |
erect, not spirally twisted, not contracted near spikelet, when dry usually with several blunt to acute ridges and sulcate, subterete to slightly compressed, to 2 times as wide as thick, (5–)10–40 cm × 0.5–1.2 mm, firm to hard, finely many-ridged at 10–20X; culm tufts not proximally bulbous. |
Leaves | sheaths stramineous, distal sheaths often splitting abaxially, slightly inflated distally, oblique, apex acute. |
distal leaf sheaths stramineous to brown or reddish proximally, green to stramineous distally, subtruncate to obtuse, membranous to papery; apex brown to red. |
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. |
5–10 × 2–4 mm; proximal scale usually empty, 3–5 mm, usually 1/2 or more as long as spikelet; floral scales 8–12 per spikelet, lanceolate (to ovate), 3.5–5 × 2–2.5 mm. |
Flowers | perianth bristles absent; anthers 0.3–0.5 mm. |
perianth bristles 6, equal, the longest equaling achene to exceeding tubercle, very slender, spinules dense; anthers 1.6–3.5 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. |
medium brown to gray or dark brown, equilaterally trigonous to compressed trigonous, rarely some biconvex, 2–2.7 × 0.7–1.3 mm, apex tapered to a distinct stramineous beak 0.2–0.9 × 0.3–0.6 mm. |
Tubercles | grayish, mostly appressed, pyramidal, often depressed, 0.1–0.2 × 0.1–0.25 mm. |
0.4–0.5 × 0.3–0.5 mm. |
Eleocharis bella |
Eleocharis suksdorfiana |
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Phenology | Fruiting spring–summer. | Fruiting late spring–summer. |
Habitat | Bare, often drying soil of stream alluvium, lake margins, wet meadows | Bogs, fens, wet meadows, springs, wet gravel near ponds |
Elevation | 200–2900 m (700–9500 ft) | (0–)1100–3300 m ((0–)3600–10800 ft) |
Distribution |
AZ; CA; ID; MT; NM; NV; OR; WA; Mexico (Chihuahua)
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CA; CO; ID; MT; NV; OR; UT; WA; AB; BC |
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.) |
Although Eleocharis suksdorfiana is usually included in E. quinqueflora, it clearly differs qualitatively as given in the key. A collection from hot springs in Ruby Valley, Elko County, Nevada, has stout perianth bristles less than half of the achene length and may represent an undescribed taxon related to E. suksdorfiana. Eleocharis suksdorfiana closely resembles E. rostellata in its achenes, tubercles, culms, and caudices; it differs in the presence of long horizontal rhizomes and the absence of stoloniferous culms. The achenes of E. suksdorfiana are often finely longitudinally ridged, but in E. rostellata they are often rugulose. Specimens from Coconino and Santa Cruz counties, Arizona, are probably E. suksdorfiana but lack achenes so cannot be identified with certainty. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 23, p. 110. | FNA vol. 23, p. 115. |
Parent taxa | Cyperaceae > Eleocharis > subg. Scirpidium | Cyperaceae > Eleocharis > subg. Zinserlingia |
Sibling taxa | ||
Synonyms | E. acicularis var. bella, E. acicularis var. minima | E. paucifora var. suksdorfiana, E. quinqueflora var. suksdorfiana |
Name authority | (Piper) Svenson: Rhodora 31: 201. (1929) | Beauverd: Bull. Soc. Bot. Genève 13: 267. (1922) |
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