Eleocharis radicans |
Eleocharis montana |
|
---|---|---|
creeping spikerush, radical fiber optic spikerush, root spikerush |
mountain spikerush |
|
Habit | Plants perennial, mat-forming; rhizomes 0.2–0.5 mm thick, longer internodes 5–10 mm, scales not evident. | Plants perennial, densely tufted or mat-forming; rhizomes mostly hidden by culms and roots, fairly long, 3 mm thick, hard, cortex persistent, longer internodes to 3 mm, scales persistent, ca. 8 mm, membranous, slightly fibrous. |
Culms | obscurely to ca. 10-ribbed when dry, terete, 1–12 cm × 0.4–1 mm, very soft, spongy. |
terete, when dry with few to many blunt ridges, 10–70 cm × 0.5–2 mm, soft to firm, internally hollow with complete transverse septa 2–5 mm apart, usually evident externally except in narrowest culms. |
Leaves | distal leaf sheaths fugaceous, colorless, translucent, apex blunt. |
distal leaf sheaths persistent, not splitting, proximally dark red, distally green or brown, slightly callose, papery, apex obtuse, tooth present, 0.3–1 mm. |
Spikelets | ovoid, 2–3 × 1–1.5 mm, apex acute; scales 5–15, 5–7 per mm of rachilla, colorless to stramineous, rarely slightly reddish, medially broadly greenish to colorless, faintly 3–5-veined, often ovate, membranous, fleshy; proximal scale 2–2.5 × 0.7 mm, other scales 1.5–2 × 0.7 mm, midrib obscure to slightly keeled, apex acute to rounded. |
ovoid, 6–21 × 3–4 mm, apex acute to obtuse; proximal scale amplexicaulous, entire; subproximal scale empty or with flower; floral scales appressed in fruit, 100–500+, (15–)30–40 per mm of rachilla, medium brown to colorless, midrib regions greenish to colorless, ovate, 1.5–2.5 × 1–1.5 mm, entire, apex rounded to subacute, carinate in distal part of spikelet. |
Flowers | perianth bristles equaling achene; anthers yellow to brown, 0.3–0.5 mm. |
perianth bristles 6–8, pale brown, medium stout, from less than 1/2 achene length to sometimes slightly exceeding tubercle, retrorsely spinulose; stamens 1; anthers dark yellow to brown, 0.6–1 mm; styles 3-fid or some 2-fid. |
Achenes | brownish, angles plus longitudinal ridges ca. 7, narrowly obovoid, 2 times longer than wide, 0.75–0.9 × 0.35–0.4 mm, trabeculae ca. 50, distinct. |
falling with scales, dark green or medium brown, obovoid to obpyriform, biconvex or sometimes some compressedtrigonous in same spikelet, lateral angles prominent, abaxial angle absent or evident, not prominent, 0.8–1.1 × 0.7–0.8 mm, neck short or absent, finely cancellate at 10–20X, sometimes finely rugulose, with 15 horizontal ridges in vertical series. |
Tubercles | brown, pyramidal, 0.15 × 0.15–0.2 mm. |
brown, pyramidal, mostly depressed, 0.2–0.35 × 0.2–0.4 mm. |
Eleocharis radicans |
Eleocharis montana |
|
Phenology | Fruiting spring–winter (Apr–Dec). | Fruiting winter–fall. |
Habitat | Stream alluvium, lake margins, meadows, seeps, bogs | Fresh temporary or artificial ponds, ditches, burned savannas, swamp margins |
Elevation | 100–1400 Ariz., Calif., Fla., La., Mich., Okla., Tex., Va. | 20–90[–2800] m (100–300[–9200] ft) |
Distribution |
HI; n Mexico; West Indies; Central America (El Salvador); South America (Argentina, Chile)
|
AL; AZ; FL; GA; LA; TX; Mexico; Central America; South America; West Indies |
Discussion | The taxonomy of the septate-culmed species here treated as Eleocharis montana and E. ravenelii should be evaluated. According to H. K. Svenson (1957), the type of E. montana from near Bogotá, Colombia, is the mountain extreme of the species; it has swollen culms with no visible septation. Specimens from Acadia and St. Landry parishes, Louisiana, are intermediate between Eleocharis montana and E. montevidensis. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
|
Source | FNA vol. 23, p. 112. | FNA vol. 23, p. 79. |
Parent taxa | Cyperaceae > Eleocharis > subg. Scirpidium | Cyperaceae > Eleocharis > subg. Eleocharis > sect. Eleocharis > ser. Eleocharis |
Sibling taxa | ||
Synonyms | Scirpus radicans, E. acicularis var. radicans, E. lindheimeri | Scirpus montanus, E. montana var. nodulosa, E. nodulosa |
Name authority | (Poiret) Kunth: Enum. Pl. 2: 142. (1837) | (Kunth) Roemer & Schultes: in J. J. Roemer et al., Syst. Veg. 2: 153. (1817) |
Web links |