Cyperus giganteus |
Cyperus ligularis |
|
---|---|---|
giant flatsedge, Mexican papyrus |
Alabama swamp flatsedge |
|
Habit | Herbs, perennial, rhizomatous, stout. | Herbs, perennial, solitary or cespitose, rhizomatous, coarse. |
Culms | roundly trigonous, 200–350 cm × 15–50 mm, glabrous. |
trigonous, (30–)60–130 cm × 1–4(–9) mm, densely papillose, otherwise glabrous. |
Leaves | bladeless. |
with cross ribs prominent, V-shaped, 30–100 cm × 5–13(–20) mm, margins, keel incisive with brownish prickles, papillose throughout, margins and midribs harshly scabrid. |
Inflorescences | spikes loosely cylindric, 15–40 × 8–16 mm; rays 5–8, ascending to erect, stiff,20–30 cm; 2d order rays 5–15 cm; bracts 10–12, ascending at 30–60°, flat, (8–) 20–45 cm × 4–12 mm; 2d order bracts (5–)15–25 cm × 1.5–5 mm; rachilla persistent, separating laterally, remaining firmly attached basally, wings 0.3–0.4 mm wide. |
spikes 3–7, densely oblong-cylindric to ± globose, 10–28(–35) × 8–12(–15) mm; rays 5–12, 1–16 cm, densely papillose; bracts 5–12, ascending at 30–75°, flat to V-shaped, 4–50(–90) cm × 1–15 mm; rachilla deciduous, wings persistent, (0.2–)0.3–0.5(–0.6) mm. |
Spikelets | (15–)50–80, slightly compressed, linear, ± quadrangular, 5–12 × 0.6–1.4 mm; floral scales 8–20, appressed, reddish beside 5-ribbed green medial part, white to hyaline near margins, ovate, 1.8–2.2 × 1.2–1.5 mm, apex acute to obtuse. |
20–80, oblong-ellipsoid, ± terete, slightly compressed, 3–7 × 1–2(–2.7) mm; distal spikelets spreading or ascending; floral scales (2–)4–7, appressed, clear to brownish, reddish streaked, medially green, 9–11-ribbed, ovate, (2–)2.5–3.3 × 1.2–2.3 mm, apex acute, mucronate. |
Flowers | anthers 0.7–1 mm (connective prolonged beyond anther as red subulate appendage 0.2–0.5 mm, its apex sometimes setose); styles 0.2–0.5 mm; stigmas (0.8–)1.2–1.8 mm. |
anthers 0.6–0.8 mm, styles 0.5–1 mm; stigmas 1–2.3 mm. |
Achenes | pale brown, sessile, oblong, 0.9–1 × 0.4–0.5 mm, apex scarcely apiculate, surfaces puncticulate. |
brown, slightly stipitate, obovoid to broadly ellipsoid, (1.2–)1.5–1.6(–1.7) × 0.6–0.8 mm, apex apiculate, surfaces puncticulate. |
Cyperus giganteus |
Cyperus ligularis |
|
Phenology | Fruiting summer. | Fruiting throughout the year. |
Habitat | Stream banks, marshes | Beaches, brackish marshes, mangrove swamps, disturbed soils, ditches, riverbanks, coastal croplands |
Elevation | 0–10 m (0–0 ft) | 0 m (0 ft) |
Distribution |
LA; TX; Mexico; Central America; South America; West Indies [Introduced in North America] |
FL; Mexico; Central America; South America; w Africa
|
Discussion | Cyperus giganteus was erroneously reported from Florida, a misidentification of C. papyrus (R. R. Haynes and A. Lasseigne 1969). Recently, some nurseries specializing in water plants have begun to offer C. giganteus under the name “Mexican papyrus.” Escaped cultivated plants may be expected in southeastern and southwestern United States. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
The papillose culms, rays, and leaves of Cyperus ligularis distinguish it from all other North American species of Cyperus. Reports of Cyperus ligularis from California (G. C. Tucker 1993b) were based on specimens of C. owanii. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 23, p. 173. | FNA vol. 23, p. 190. |
Parent taxa | Cyperaceae > Cyperus > subg. Cyperus | Cyperaceae > Cyperus > subg. Cyperus |
Sibling taxa | ||
Synonyms | Mariscus rufus | |
Name authority | Vahl: Enum. Pl. 2: 364. (1805) | Linnaeus: Syst. Nat. ed. 10, 2: 867. (1759) |
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