Cyperus lanceolatus |
Cyperus tetragonus |
|
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epiphytic flatsedge |
fourangle flatsedge |
|
Habit | Herbs, perennial, cespitose, rhizomatous. | Herbs, perennial, cespitose, rhizomatous. |
Culms | trigonous, compressed, 15–75 cm × 0.5–3 mm, glabrous. |
trigonous, (20–) 30–80 cm × 1–2.5 mm, glabrous or occasionally with scattered prickles on distal angles. |
Leaves | 1–3, 5–30 cm × 1–2 mm. |
9–11, flat to slightly V-shaped, 25–80 cm × 3.5–10 mm. |
Inflorescences | spikes 1(–2), ovoid, 5–23 × 9–21 mm; rays 2–3(–4), 0–15 mm; if rays absent, head single, compact, sessile, (12–)15–20 mm diam.; bracts 2–3, horizontal to vertical, 2–14 cm × 0.5–3.5 mm. |
spikes (1–)3–6, loosely cylindric or oblong with parallel sides, 1.5–4 cm × 10–17 mm; rays 6–12, 2–25 cm, glabrous or rarely scabridulous proximal to spikes; bracts 6–11, ascending at 45°, flat, (1–)10–20(–26) cm × 1–10 mm; rachilla deciduous, wings persistent, 0.4–0.5 mm wide. |
Spikelets | 1–6, oblong-lanceoloid, 5–26 × 2–3 mm; floral scales 12–54, closely imbricate, laterally yellowish brown, medially pale brown, occasionally greenish, laterally 1-ribbed, medially 3-ribbed, distinctly 2-keeled basally, ovate, 1.8–2.6 × 1.4–1.7 mm, apex obtuse. |
10–60, narrowly ellipsoid, quadrangular, 5–8 × 1.5–2 mm; floral scales persistent, (2–)3–7, appressed, clear at maturity, laterally reddish to purplish brown, medially greenish, often erose at maturity, laterally 3–5-ribbed, medially 3-ribbed, ovate-elliptic, 2.5–3.2 × 1.8–2.1 mm, apex obtuse. |
Flowers | stamens 2; anthers 0.4–0.5 mm, connectives not prolonged; styles 0.3–1 mm; stigmas 0.6–0.8(–1) mm. |
anthers 0.8–1 mm; styles 0.3–0.5 mm; stigmas 2–2.5 mm. |
Achenes | brown, network of ridges forming isodiametric or square cells, stipitate, obovoid to ellipsoid, 1.1–1.3 × (0.5–)0.6 mm, apex acute to broadly rounded, surfaces minutely punctate or finely papillose. |
brown to reddish brown, sessile, oblong-ovoid to broadly ellipsoid, slightly dorsiventrally flattened, 1.8–2 × 0.7–0.8 mm, apex obtuse, apiculate, surfaces papillose to puncticulate. |
Cyperus lanceolatus |
Cyperus tetragonus |
|
Phenology | Fruiting summer. | Fruiting summer–fall (Jun–Nov). |
Habitat | Marshes | Open woods, thickets, barrier islands |
Elevation | 0–100 m (0–300 ft) | 0–1000 m (0–3300 ft) |
Distribution |
AL; FL; GA; LA; TX; Mexico; Central America; South America; Africa
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AL; AZ; FL; GA; MS; NC; NM
|
Discussion | The status of Cyperus pringlei from the southwestern United States requires further study. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
|
Source | FNA vol. 23, p. 162. | FNA vol. 23, p. 189. |
Parent taxa | Cyperaceae > Cyperus > subg. Pycreus | Cyperaceae > Cyperus > subg. Cyperus |
Sibling taxa | ||
Synonyms | C. densus, C. humboldtianus, C. lanceolatus var. compositus, Pycreus densus | C. pringlei, C. tetragonus var. pringlei, Mariscus tetragonus |
Name authority | Poiret: in J. Lamarck et al., Encycl. 7: 245. (1806) | Elliott: Sketch Bot. S. Carolina 1: 71. (1821) |
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