Cyperus involucratus |
Cyperus sanguinolentus |
|
---|---|---|
umbrella flatsedge, umbrella-plant |
purpleglume flatsedge |
|
Habit | Herbs, perennial, cespitose, rhizomatous. | Herbs, perennial; rhizomes ± horizontal, to 12 cm × 0.8–1.2 mm. |
Culms | trigonous, 30–150 cm × 1–5(–8) mm. |
± terete to roundly trigonous, 3–25(–60) cm × 0.3–2 mm, glabrous. |
Leaves | bladeless. |
1–3, V-shaped, 1–8(–15) cm × 1–2 mm. |
Inflorescences | heads digitate, 15–30(–36) mm diam.; rays (14–)20–22, (2–)5–12(–20) cm; 2d order rays 0.3–3(–4) cm; 3d order rays sometimes present, 0.3–2.5 cm; bracts (4–)18–22, ± horizontal, flat, 15–27 cm × (1.5–)8–12 mm. |
spike 1, loosely ovoid, 7–14 × 8–20 mm; rays (0–)1–4, to 2(–3) cm; bracts 2–4, horizontal to ascending at 30(–45)°, V-shaped to flat, 1–8(–18) cm × 0.5–1.5(–2) mm. |
Spikelets | 8–20, ovoid to linear-lanceoloid, compressed, 5–25 × 1.5–2 mm; floral scales 8–28, laterally whitish or light brown, ± hyaline, medially light brown, laterally ribless, medially 3-ribbed, 2-keeled in proximal 30–60%, deltate-ovate, 1.6–2.4 × (1–)1.2–1.5(–1.7) mm, apex acute. |
3–5(–14), oblong to linear-lanceoloid, 8–18 × 2–2.6(–3) mm; floral scales (6–)10–26(–32), laterally clear to light brown, sometimes with purplish margins, medially light brown, 2-keeled, laterally ribless, medially 2–3-ribbed, oblong to ovate, 1.9–2.2(–2.7) × 1.8–2.3 mm, apex obtuse. |
Flowers | stamens 3; anthers 0.7–1 mm; styles 0.5–1 mm; stigmas 0.6–1 mm. |
stamens 3; anthers ellipsoid, 0.3–0.6 mm, connective not prolonged; styles 0.6–1 mm; stigmas 1–1.5 mm. |
Achenes | brown, sessile or stipitate, broadly ellipsoid, 0.6–0.8 × 0.4–0.6 mm, stipe if present to 0.1 mm, apex obtuse, apiculate, surfaces puncticulate. |
brown, ± stipitate, obovoid to ovoid, 1–1.4 × 0.6–0.8 mm, apex truncate, apiculate, surfaces minutely punctate. |
Cyperus involucratus |
Cyperus sanguinolentus |
|
Phenology | Fruiting early summer–fall. | Fruiting late summer–fall. |
Habitat | Damp, disturbed soils, ditches, stream banks | Emergent shorelines, ditches |
Elevation | 0–100(–800) m (0–300(–2600) ft) | 20 m (100 ft) |
Distribution |
CA; FL; LA; TX; e Africa [Introduced in North America]
|
AL; GA; LA; MS; Asia; Africa [Introduced in North America] |
Discussion | Cyperus involucratus has been collected in New York (R. S. Mitchell and G. C. Tucker 1997). Cyperus involucratus is widely cultivated as a water plant in greenhouses and outdoors in warm-temperate or tropical climates. It has long been misidentified in the flora as C. alternifolius Linnaeus, an endemic of Madagascar (G. C. Tucker 1983). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Cyperus sanguinolentus is the only rhizomatous, distigmatic Cyperus in the eastern United States. An early collection from Louisiana was described as C. louisianensis, supposedly endemic. Recent field work and morphometric studies convincingly showed it to be an introduction of the Asian C. sanguinolentus) (J. R. Carter and C. T. Bryson 2001. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 23, p. 150. | FNA vol. 23, p. 161. |
Parent taxa | Cyperaceae > Cyperus > subg. Pycnostachys | Cyperaceae > Cyperus > subg. Pycreus |
Sibling taxa | ||
Synonyms | C. louisianensis, Pycreus sanguinolentus | |
Name authority | Rottbøll: Descr. Pl. Rar., 22. (1772) | Vahl: Enum. Pl. 2: 351. (1805) |
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