Cyperus giganteus |
Cyperus parishii |
|
---|---|---|
giant flatsedge, Mexican papyrus |
Parish flatsedge, Parish's flatsedge, Parish's nutgrass |
|
Habit | Herbs, perennial, rhizomatous, stout. | Herbs, annual, cespitose. |
Culms | roundly trigonous, 200–350 cm × 15–50 mm, glabrous. |
trigonous, 5–25 cm × 1–1.5 mm, glabrous. |
Leaves | bladeless. |
|
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 loosely ovoid, 15–25 mm wide; rays 1–6, 2–7 cm; bracts 2–5, 3–20 cm, ascending; rachilla deciduous, winged. |
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. |
5–30, linear, flattened, 6–22 × 1.5–2.2 mm; floral scales ± deciduous, (4–)8–12, red, reddish purple, or reddish brown, medially green, elliptic, laterally 2–4-ribbed, 2.3–3.1 × 1.2–2 mm, apex acute to obtuse. |
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 0.3–0.4 mm; styles 1 mm; stigmas 1.3–1.6 mm. |
Achenes | pale brown, sessile, oblong, 0.9–1 × 0.4–0.5 mm, apex scarcely apiculate, surfaces puncticulate. |
brown to dark purplish brown, broadly ellipsoid, 1–1.3 × 0.6–0.9 mm, surfaces puncticulate. |
Cyperus giganteus |
Cyperus parishii |
|
Phenology | Fruiting summer. | Fruiting summer. |
Habitat | Stream banks, marshes | Stream banks, desert washes, arroyos, roadsides |
Elevation | 0–10 m (0–0 ft) | 0 800 m (0 2600 ft) |
Distribution |
LA; TX; Mexico; Central America; South America; West Indies [Introduced in North America] |
AZ; CA; NM
|
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.) |
|
Source | FNA vol. 23, p. 173. | FNA vol. 23, p. 170. |
Parent taxa | Cyperaceae > Cyperus > subg. Cyperus | Cyperaceae > Cyperus > subg. Cyperus |
Sibling taxa | ||
Synonyms | C. congestus var. parishii | |
Name authority | Vahl: Enum. Pl. 2: 364. (1805) | Britton ex Parish: Bull. S. Calif. Acad. Sci. 3: 52, plate 3. (1904) |
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