Cyperus prolixus |
Cyperus lanceolatus |
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mosquito flatsedge |
epiphytic flatsedge |
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Habit | Herbs, perennial; rhizomes 3–20 cm × 1–2 cm, indurate. | Herbs, perennial, cespitose, rhizomatous. |
Culms | stoutly trigonous, thickened, 50–300 cm × 5–30 mm, basally indurate, glabrous. |
trigonous, compressed, 15–75 cm × 0.5–3 mm, glabrous. |
Leaves | V-shaped, with cross ribs, 40–130 cm × 10–15 mm, margins and keel scabrid. |
1–3, 5–30 cm × 1–2 mm. |
Inflorescences | spikes appressed-ascending, narrowly cylindric, (2–)3–45 mm × (4–)7–10 mm; rays (5–)9–12, 2–22(–30) cm; 2d order rays distinctly flattened, 1–10 cm; 3d order rays flattened, 0.5–3 cm; rachis 2.5–4 cm; bracts (6–)9–10, ascending at 45–75°, V- or inversely W-shaped, (5–)15–90 cm × 0.5–20 mm; rachilla persistent, wings 0.2–0.4 mm wide. |
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. |
Spikelets | (4–)10–35, appressed-ascending, compressed, linear, 7–12(–15) × 0.6–1.2 mm; floral scales deciduous, 6–20, marginally clear, laterally brown, medially green, laterally 2–3-ribbed, medially 1-ribbed, oblong-ovate, (3.2–) 3.8–4.3 × 1.2–1.7 mm, apex spreading, acute to obtuse, mucronulate. |
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. |
Flowers | anthers 0.7–0.9 mm, connective apex bright red, oblong, to 0.1 mm; styles 0.8–1.3 mm; stigmas 2–3.3 mm. |
stamens 2; anthers 0.4–0.5 mm, connectives not prolonged; styles 0.3–1 mm; stigmas 0.6–0.8(–1) mm. |
Achenes | brown, sessile, narrowly ellipsoid, 1.8–2.5 × 0.8–1.3 mm, apex ± acute, not apiculate, surfaces puncticulate. |
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. |
Cyperus prolixus |
Cyperus lanceolatus |
|
Phenology | Fruiting summer. | Fruiting summer. |
Habitat | Coastal marshes | Marshes |
Elevation | 0–10 m [0–30 ft] | 0–100 m [0–300 ft] |
Distribution |
LA; Mexico; Central America; South America |
AL; FL; GA; LA; TX; Mexico; Central America; South America; Africa
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Discussion | Cyperus prolixus produces large plants, similar in habit to C. giganteus and C. papyrus but easily distinguished by flattened rays. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Source | FNA vol. 23, p. 167. | FNA vol. 23, p. 162. |
Parent taxa | ||
Sibling taxa | ||
Synonyms | C. amplissimus | C. densus, C. humboldtianus, C. lanceolatus var. compositus, Pycreus densus |
Name authority | Kunth: in A. von Humboldt et al., Nov. Gen. Sp. 1: 206. (1816) | Poiret: in J. Lamarck et al., Encycl. 7: 245. (1806) |
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