Cyperus lanceolatus |
Cyperus polystachyos |
|
---|---|---|
epiphytic flatsedge |
many-spike flatsedge |
|
Habit | Herbs, perennial, cespitose, rhizomatous. | Herbs, perennial (annual?), cespitose. |
Culms | trigonous, compressed, 15–75 cm × 0.5–3 mm, glabrous. |
trigonous or ± terete, (3–)20–45(–70) cm × (0.8–) 1.2–2 mm, glabrous. |
Leaves | 1–3, 5–30 cm × 1–2 mm. |
(2–) 6–10(–16), flat to V-shaped, (2–) 10–30(–60) cm × 1–4 mm. |
Inflorescences | spikes 1(–2), ovoid, 5–23 × 9–21 mm; rays 2–3(–4), 0–15 mm; if rays absent, head single, compact, sessile, (12–)15–20 mm diam.; bracts 2–3, horizontal to vertical, 2–14 cm × 0.5–3.5 mm. |
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. |
Spikelets | 1–6, oblong-lanceoloid, 5–26 × 2–3 mm; floral scales 12–54, closely imbricate, laterally yellowish brown, medially pale brown, occasionally greenish, laterally 1-ribbed, medially 3-ribbed, distinctly 2-keeled basally, ovate, 1.8–2.6 × 1.4–1.7 mm, apex obtuse. |
(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. |
Flowers | stamens 2; anthers 0.4–0.5 mm, connectives not prolonged; styles 0.3–1 mm; stigmas 0.6–0.8(–1) mm. |
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. |
Achenes | brown, network of ridges forming isodiametric or square cells, stipitate, obovoid to ellipsoid, 1.1–1.3 × (0.5–)0.6 mm, apex acute to broadly rounded, surfaces minutely punctate or finely papillose. |
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. |
Cyperus lanceolatus |
Cyperus polystachyos |
|
Phenology | Fruiting summer. | Fruiting summer–early fall. |
Habitat | Marshes | Shores, ditches, swales between dunes |
Elevation | 0–100 m (0–300 ft) | 0–200 m (0–700 ft) |
Distribution |
AL; FL; GA; LA; TX; Mexico; Central America; South America; Africa
|
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
|
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. 162. | FNA vol. 23, p. 160. |
Parent taxa | Cyperaceae > Cyperus > subg. Pycreus | Cyperaceae > Cyperus > subg. Pycreus |
Sibling taxa | ||
Synonyms | C. densus, C. humboldtianus, C. lanceolatus var. compositus, Pycreus densus | C. brizaeus, C. polystachyos var. leptostachyus, Pycreus polystachyos |
Name authority | Poiret: in J. Lamarck et al., Encycl. 7: 245. (1806) | Rottbøll: Descr. Pl. Rar., 21. (1772) |
Web links |