Eleocharis flavescens

(Poiret) Urban

Symb. Antill. 4: 116. 1903.

Common names: Pale spike-rush wrinkle-sheathed spike-rush
Illustrated
Basionym: Scirpus flavescens Poiret in J. Lamarck et al., Encycl. 6: 756. 1804
Treatment appears in FNA Volume 23. Treatment on page 100. Mentioned on page 63, 101.
Revision as of 18:37, 6 November 2020 by RevisionBot (talk | contribs) (Bot: Adding category Revised Since Print)
(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)

Plants with creeping rhizomes 0.5–1 mm thick. Culms 3–42 cm × 0.3–0.6 mm. Leaves: distal leaf sheaths often disintegrating, thinly membranous-translucent, inflated distally, often wrinkled, apex blunt. Spikelets ellipsoid, 1.5–9 × 1–3.5 mm, apex acute to acuminate; proximal scale without flower, not amplexicaulous; floral scales to 65, 5–7 per mm of rachilla, loosely appressed to appressed, elliptic, 1–3 × 0.4–1.6 mm, membranous, apex acute. Flowers: perianth bristles (0–)5–8, typically 7, white to stramineous, spinules dense to few; styles 2-fid, rarely 3-fid. Achenes stramineous to green or dark brown, biconvex, rarely trigonous, obovoid to obpryiform, 0.4–1.1 × 0.3–0.8 mm, very finely reticulate at 40X. Tubercles whitish to stramineous or green, 0.2–0.7 × 0.2–0.4 mm, apex acute to acuminate.

Distribution

V23 148-distribution-map.jpg

N.B., N.S., Ont., Que., Ala., Ariz., Ark., Calif., Conn., Del., Fla., Ga., Idaho, Ill., Ind., La., Maine, Mass., Md., Mich., Minn., Miss., Mont., N.C., N.H., N.J., N.Y., Ohio, Pa., R.I., S.C., Tex., Utah, Va., Vt., Wis., Wyo., temperate North America, West Indies, South America.

Discussion

Varieties 2 (2 in the flora).

The varieties of Eleocharis flavescens are difficult to delimit, especially in the south, and identifications of some specimens to variety are problematic.

Selected References

None.

Key

1 Achenes red-brown to dark brown when ripe, 0.4–0.8(–1.1) × 0.3–0.6 mm, apex rarely highly constricted proximal to tubercle; flowers with perianth bristles typically shorter than to as long as achene. Eleocharis flavescens var. flavescens
1 Achenes green to golden-brown, 0.5–1.1 × 0.4–0.8 mm, often highly constricted proximal to tubercle; flowers with perianth bristles typically longer than achene. Eleocharis flavescens var. olivacea
... more about "Eleocharis flavescens"
Francis J. Menapace +
(Poiret) Urban +
Scirpus flavescens +
Pale spike-rush +  and wrinkle-sheathed spike-rush +
N.B. +, N.S. +, Ont. +, Que. +, Ala. +, Ariz. +, Ark. +, Calif. +, Conn. +, Del. +, Fla. +, Ga. +, Idaho +, Ill. +, Ind. +, La. +, Maine +, Mass. +, Md. +, Mich. +, Minn. +, Miss. +, Mont. +, N.C. +, N.H. +, N.J. +, N.Y. +, Ohio +, Pa. +, R.I. +, S.C. +, Tex. +, Utah +, Va. +, Vt. +, Wis. +, Wyo. +, temperate North America +, West Indies +  and South America. +
Symb. Antill. +
Illustrated +
Eleocharis +
Eleocharis flavescens +
Eleocharis (sect. Eleogenus) ser. Maculosae +
species +