Cyperus prolixus |
Cyperus dipsaceus |
|
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mosquito flatsedge |
teasel-flatsedge, Wright's flatsedge |
|
Habit | Herbs, perennial; rhizomes 3–20 cm × 1–2 cm, indurate. | Herbs, perennial, rhizomatous. |
Culms | stoutly trigonous, thickened, 50–300 cm × 5–30 mm, basally indurate, glabrous. |
trigonous, (30–)45–80 cm × (0.8–)1.2–2.2 mm, glabrous. |
Leaves | V-shaped, with cross ribs, 40–130 cm × 10–15 mm, margins and keel scabrid. |
flat to V-shaped, becoming trigonous apically, 15–30 cm × 0.5–3.2 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 oblong-cylindric, densely spicate, ± truncate at base, (9–)12–22 × (4–)6–12 mm; rays 2–4(–5), (1.5–)2.5–6 cm; bracts 4–6, longest erect or nearly so, larger ones flat or V-shaped, smaller capillary, trigonous, 3–24 cm × 0.4–3.6 mm; rachilla ± deciduous, wings 0.2–0.4 mm wide. |
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. |
(10–)20–60, oblong to linear-lanceoloid, compressed-quadrangular, 3–9 × 2–3.4 mm; floral scales deciduous, 2–4(–8), spreading, medially green, laterally stramineous, dull whitish or pale reddish brown, often red-dotted laterally, (3–)7–9-ribbed, ovate-lanceolate, (2–)2.2–2.8(–3) × (1–)1.2–1.8 mm, apex acute, weakly 3-dentate, mucro 0.2–0.6 mm, with apical tuft of crystalline prickles. |
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. |
anthers 0.4–0.9 mm; styles 1–1.4 mm; stigmas 1–1.6 mm. |
Achenes | brown, sessile, narrowly ellipsoid, 1.8–2.5 × 0.8–1.3 mm, apex ± acute, not apiculate, surfaces puncticulate. |
brown, ± stipitate, broadly ellipsoid, 1.4–1.5(–1.6) × 0.8–0.9 mm, 0.1 × 0.1–0.2 mm, apex ± truncate, apiculate, surfaces papillose. |
Cyperus prolixus |
Cyperus dipsaceus |
|
Phenology | Fruiting summer. | Fruiting late summer. |
Habitat | Coastal marshes | Seepage slopes in montane forests |
Elevation | 0–10 m [0–30 ft] | 1000–1500 m [3300–4900 ft] |
Distribution |
LA; Mexico; Central America; South America |
AZ; NM; Mexico |
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.) |
|
Source | FNA vol. 23, p. 167. | FNA vol. 23, p. 174. |
Parent taxa | ||
Sibling taxa | ||
Synonyms | C. amplissimus | C. wrightii |
Name authority | Kunth: in A. von Humboldt et al., Nov. Gen. Sp. 1: 206. (1816) | Liebmann: Kongel. Danske Vidensk. Selsk. Skr., Naturvidensk. Math. Afd., ser. 5, 2: 219. (1850) |
Web links |