Cyperus polystachyos |
Cyperus planifolius |
|
---|---|---|
many-spike flatsedge |
flatleaf flatsedge |
|
Habit | Herbs, perennial (annual?), cespitose. | |
Culms | trigonous or ± terete, (3–)20–45(–70) cm × (0.8–) 1.2–2 mm, glabrous. |
trigonous, 25–50(–80) cm × 0.8–2.6 mm, glabrous. |
Leaves | (2–) 6–10(–16), flat to V-shaped, (2–) 10–30(–60) cm × 1–4 mm. |
flat to V-shaped, 30–80 cm × 3–10 mm. |
Inflorescences | spike 1, loosely ovoid to densely turbinate, 12–40 × 10–25 mm; rachis 3–10 mm; rays 1–8(–12), 0.5–3(–6) cm; 2d order rays absent; if rays absent, inflorescence single dense cluster of spikelets, 12–40 mm diam.; bracts (3–)4–6(–7), horizontal to ascending at 45°, flanged V-shaped, (2–)5–15(–23) cm × 1–4 mm. |
spikes ovoid, 1.5–3 × 1.5–3 cm; rays 4–7, 1–10 cm; 2d order rays occasionally present, 0.5–2 cm, rays often not elongate, inflorescence then capitate, 2–5 cm diam.; bracts 4–8, horizontal to ascending at 30°, flat to V-shaped, longest 6–35 cm × (1.5–)4–8 mm; rachilla persistent, wings 0.4–0.6 mm wide. |
Spikelets | (5–)15–30(–40), spreading to appressed-ascending, linear-lanceoloid to linear, compressed, 8–18(–40) × (1–)1.3–1.6(–2) mm; floral scales (8–)12–25(–66), laterally stramineous to light brown, medially green, laterally ribless, medially 3–5-ribbed, oblong, (1.5–)1.8–2.4 × (1–)1.2–1.4 mm, apex acute to ± acute, mucronate. |
(10–)20–60, reddish brown, flattened elliptic in cross section, linear-lanceoloid, 6–22 cm × (1–)2–3(–4) mm; floral scales deciduous, 6–16, medially greenish, laterally reddish brown to brown, medially 3–5-ribbed, laterally 3–5-ribbed, ovate-lanceolate to ± orbiculate, 2.5–3 × 1.4–1.8 mm, apex acute to obtuse and mucronulate. |
Flowers | stamens 2; anthers (0.4–)0.5–0.8 mm, connective not prolonged; styles 0.6–1(–1.4) mm; stigmas (1–)1.4–2 mm. |
anthers 0.7–1.8 mm; styles (0.3–)1.2–2.8 cm; stigmas (1–)2–3 mm. |
Achenes | light to dark brown, oblong, (0.8–)0.9–1.1(–1.2) × 0.4–0.5(–0.6) mm, base cuneate to ± stipelike, apex truncate, apiculate, surfaces punctate to minutely punctate with raised cells. |
brownish to black, stipitate or sessile, ellipsoid to obovoid or oblong, 1.3–2 × 0.75–1(–1.1) mm, apex obtuse, apiculate or not, surfaces coarsely punctate. |
Herb | , perennial, cespitose, rhizomatous. |
|
Cyperus polystachyos |
Cyperus planifolius |
|
Phenology | Fruiting summer–early fall. | Fruiting throughout the year. |
Habitat | Shores, ditches, swales between dunes | Coral sand beaches, coastal rock outcrops |
Elevation | 0–200 m (0–700 ft) | 0–10 m (0–0 ft) |
Distribution |
AL; DC; DE; FL; GA; KY; LA; MA; MD; ME; MS; NC; NJ; NY; OK; PA; SC; TX; VA; WV; Mexico; Central America; South America; Asia; Africa
|
FL; GA; Mexico; West Indies; Central America (Belize, Honduras) |
Discussion | Cyperus polystachyos is polymorphic. Adequate understanding of the infraspecific variations of C. polystachyos requires a worldwide examination, which is beyond the scope of this study. The segregates, C. fugax and C. filicinus, are recognized here; they have been usually accepted by recent workers (e.g., M. L. Fernald 1950; H. A. Gleason and A. Cronquist 1991). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
|
Source | FNA vol. 23, p. 160. | FNA vol. 23, p. 172. |
Parent taxa | Cyperaceae > Cyperus > subg. Pycreus | Cyperaceae > Cyperus > subg. Cyperus |
Sibling taxa | ||
Synonyms | C. brizaeus, C. polystachyos var. leptostachyus, Pycreus polystachyos | C. brizaeus, C. brunneus, C. purpurascens |
Name authority | Rottbøll: Descr. Pl. Rar., 21. (1772) | Richard: Actes Soc. Hist. Nat. Paris 1: 106. (1792) |
Web links |