Cyperus surinamensis |
Cyperus prolifer |
|
---|---|---|
tropical flatsedge |
miniature flatsedge |
|
Habit | Herbs, annual or short-lived perennial, annuals cespitose; rhizomes absent. | Herbs, perennial, cespitose, rhizomatous. |
Culms | 2–6, trigonous, (10–)35–80 cm × 0.5–2(–4) mm, scabridulous with retrorse prickles (infrequently glabrous or rarely also with extrorse prickles). |
trigonous to terete, 20–100 cm × 2–6 mm, soft (flattened in drying), glabrous, often flopping over and rooting at base of rays. |
Leaves | 3–9, V-shaped, (12–)25–45(–65) cm × 2–10 mm; blades and bracts without cross ribs. |
blades reduced to sheath. |
Inflorescences | heads umbellate, 10–20(–30) mm diam.; rays 4–12, 1–6 cm, minutely scabridulous with retrorse prickles; 2d order rays often present, 1–2(–3) cm; 3d order rays rarely present, 0.5–1.5 cm; bracts 3–8, approximately horizontal to ascending at 30°, V-shaped to flat, 2–15(–34) cm × 1–4(–5) mm. |
rays 100–250, 5–16 cm; 2d order rays 0.5–5 cm; bracts 2–3, horizontal or reflexed, 4–12 cm × 1.5–4 mm. |
Spikelets | (6–)15–40(–65), greenish white, linear to linear-oblong, (3–)4–12(–15) × 1.5–2.5 mm; floral scales 10–50(–65), laterally pale yellow, light brown, or reddish brown, 2-keeled, medially 3-ribbed, lanceolate, 1–1.5 × 0.8–0.9 mm, distinctly reticulate, often scabridulous near apex. |
1–30, linear-lanceoloid, ellipsoid to narrowly ovoid, compressed-quadrangular, 6–17 × 1–1.5 mm; floral scales 5–12, reddish brown, 1–3-ribbed, 1.2–1.7 × 0.7–0.9 mm, apex mucronulate. |
Flowers | stamen 1; anthers 0.5 mm; styles 0.8–1.1 mm; stigmas 0.5 mm. |
stamens 3; anthers 1–1.2 mm; styles 0.3 mm; stigmas 1–1.3 mm. |
Achenes | brown to reddish brown, slightly stipitate, narrowly ellipsoid, 0.7–0.9 × 0.2–0.4 mm, apex apiculate, surfaces papillate or obscurely reticulate to rugulose. |
brown, obovoid, 0.4 × 0.2 mm, base stipelike to nearly cuneate, apex obtuse, surfaces finely reticulate. |
Cyperus surinamensis |
Cyperus prolifer |
|
Phenology | Fruiting late spring–early fall. | Fruiting summer. |
Habitat | Moist sunny areas with disturbed soils | Pond shores, marshes |
Elevation | 0–200 m (0–700 ft) | 0–200 m (0–700 ft) |
Distribution |
AL; AR; FL; GA; KS; LA; MS; OK; SC; TN; TX; Mexico; Central America; South America
|
CA; FL; tropical e Africa [Introduced in North America] |
Discussion | Cyperus surinamensis is distinguished readily from all other species of the genus in the New World by the usual presence of retrorse prickles on the culms and rays. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Cyperus prolifer has long been cultivated in fish ponds and water gardens and has been reported under the name C. isocladus. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 23, p. 153. | FNA vol. 23, p. 152. |
Parent taxa | Cyperaceae > Cyperus > subg. Pycnostachys | Cyperaceae > Cyperus > subg. Pycnostachys |
Sibling taxa | ||
Synonyms | C. isocladus | |
Name authority | Rottbøll: Descr. Pl. Rar., 20. (1772) | Lamarck: in J. Lamarck and J. Poiret, Tabl. Encycl. 1: 147. (1791) |
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