Eleocharis melanocarpa |
Eleocharis ovata |
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black-fruit spike-rush, black-fruit spikesedge |
ovate spike-rush, ovoid spike-rush, ovoid spikesedge, éléocharide ovale |
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Culms | to 2 times wider than thick, 35–60(–70) cm × 0.5–1.3 mm, hard, usually with to 10 blunt ribs, at 20X often finely ridged and minutely granular. |
2–35 cm × 0.3–1 mm. |
Leaves | distal leaf sheaths brown to reddish. |
apex of distal leaf sheath obtuse to acute, tooth to 0.2 mm. |
Spikelets | 3–12 × 3–4 mm; proximal scale amplexicaulous, 3.5–4 mm, midrib region very broad and fleshy, apex entire; subproximal scale with a flower; floral scales 30–40, 8–10 per mm of rachilla, orange-brown to stramineous, midrib region stramineous, broadly ovate, papery or sometimes membranous, 3–4 × 2 mm, apex entire, rounded. |
ovoid, 2–8 × 2–4 mm, apex acute (to blunt); floral scales 25–100+, ca. 10 per mm of rachilla, orange-brown, rarely stramineous, ovate, 1.5–2 × 1 mm, midribs often keeled in distal part of spikelet, apex rounded to subacute. |
Flowers | perianth bristles present, sometimes rudimentary, brown, length variable, obscurely retrorsely spinulose; anthers brown, 1.7–2.2 mm. |
perianth bristles present, rarely absent, (5–)6–7, brown, fairly slender, exceeding tubercle; stamens 2(–3); anthers brown, 0.3 mm; styles 2-fid or some 3-fid. |
Achenes | subdeltoid in outline, sometimes broadly obpyriform, equilaterally trigonous, angles prominent, 0.9–1.2 × 0.7–1.1 mm, apex truncate. |
0.75–1 × 0.6–0.85 mm. |
Tubercles | sessile, depressed-pyramidal, often apiculate, as wide as achene, 0.3–0.5 × 0.7–1.1 mm. |
deltoid, 0.3–0.5 × 0.3–0.5 mm, 3/5 of to as high as wide, 1/3–2/3 as high and 1/2–3/4 as wide as achene. |
2n | = 10. |
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Eleocharis melanocarpa |
Eleocharis ovata |
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Phenology | Fruiting summer. | Fruiting summer–fall. |
Habitat | Fresh, oligotrophic, acid, sandy or peaty, often drying shores, ponds, ditches | Fresh, often drying shores, lake and stream beds, bogs, tidal estuaries, disturbed places |
Elevation | 10–300 m (0–1000 ft) | 10–700 m (East), 1500–2000 m (Arizona) (0–2300 ft (East), 4900–6600 ft (Arizona)) |
Distribution |
AL; FL; GA; IN; MA; MI; NC; NY; RI; SC; TX; VA
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AZ; CT; IA; IL; IN; KY; MA; ME; MI; MN; MO; NH; NJ; NY; OH; OK; OR; PA; VA; VT; WA; WI; WV; AB; BC; NB; NL; NS; ON; PE; QC; Eurasia
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Discussion | Eleocharis melanocarpa is reported from Rhode Island; I have not seen a voucher specimen. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Although Eleocharis ovata has often been confused with E. obtusa, B. M. H. Larson and P. M. Catling (1996) showed that these species may be distinguished by non-overlapping widths of the tubercles, at least in Canada. The records of E. ovata in New Brunswick, Newfoundland, Nova Scotia, and Prince Edward Island are based on B. M. H. Larson and P. M. Catling (1996) and the records in Illinois, Indiana, Missouri, Montana, New Jersey, Oregon, and Washington are based on D. M. Hines (1975). Eleocharis ovata probably also occurs in Manitoba and Saskatchewan. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 23, p. 89. | FNA vol. 23, p. 103. |
Parent taxa | Cyperaceae > Eleocharis > subg. Eleocharis > sect. Eleocharis > ser. Melanocarpae | Cyperaceae > Eleocharis > subg. Eleocharis > sect. Eleogenus > ser. Ovatae |
Sibling taxa | ||
Synonyms | Scirpus ovatus, E. obtusa var. ovata, E. ovata var. heuseri | |
Name authority | Torrey: Ann. Lyceum Nat. Hist. New York 3: 311. (1836) | (Roth) Roemer & Schultes: in J. J. Roemer et al., Syst. Veg. 2: 152. (1817) |
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