Cyperus reflexus |
Cyperus gracilis |
|
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bentawn flatsedge |
slimjim flatsedge |
|
Habit | Herbs, perennial, cespitose; rhizomes elongate, scaly, 2–3 mm wide. | Herbs, annual or perennial. |
Culms | roundly trigonous to terete, 30–80 cm × 1–1.6 mm, glabrous. |
weak, often arching, basally culmlike, weakly 4(–5)-angled, 10–30 cm × 0.2–0.4 mm, glabrous. |
Leaves | 1–6, 10–40 cm, glabrous or essentially so. |
1–4, 3–25 cm × 1–1.5 mm. |
Inflorescences | heads ovoid to pyramidal, 9–15 mm diam.; rays 0 or 3–6, 0.5–4 cm, glabrous; bracts 3–4, longest erect, appearing as continuation of culm, others horizontal to ascending, 4–17 cm × 1.5–4 mm. |
rays absent, often proliferous; bracts 2–4, longest erect, looking like continuation of culm, V-shaped, 3–6 cm × 1–3 mm. |
Spikelets | 25–60, reddish with contrasting yellowish or greenish edges, oblong-lanceoloid, strongly compressed, 5–6(–15) × 1.5–2.5 mm; floral scales 10–22, laterally reddish, medially yellowish green, 2-keeled, laterally strongly 1-ribbed on each side, proximally grooved, ovate-elliptic, 1.4–2.2 × 0.8–1.5 mm, apex acute, apically scabridulous (sometimes glabrous). |
1–3(–6), narrowly ellipsoid, weakly compressed, 5–10 × 2 mm; floral scales 8–16, laterally whitish or dull stramineous, medially green, weakly 3–4-ribbed, broadly ovate, 2.5 × 2 mm, apex acute to mucronate, mucro slightly excurved, 0.2–0.3 mm. |
Flowers | stamen 1; anthers 0.6–1 mm; styles 0.3–0.5 mm; stigmas 0.3–0.6 mm. |
stamens 3; styles 0.8 mm; stigmas 1–1.3 mm. |
Achenes | reddish brown, stipitate, ovoid-ellipsoid, 0.8–0.9 × 0.3–0.4 mm, stipe 0.1–0.2 mm, apex acute to acuminate, surfaces reticulate or subtly rugulose. |
brown, stipitate, obovoid, abaxial angle more prominent than adaxial ones, 0.7 × 0.7 mm, apex emarginate, surfaces glabrous. |
Cyperus reflexus |
Cyperus gracilis |
|
Phenology | Fruiting late spring–fall (May–Oct). | Fruiting summer–early fall. |
Habitat | Muddy soils or shallow waters | Disturbed, moist areas |
Elevation | 0–200 m (0–700 ft) | 0–100 m (0–300 ft) |
Distribution |
FL; LA; OK; TX; Mexico; Central America (Costa Rica) |
CA; Australia [Introduced in North America] |
Discussion | Cyperus reflexus is recognized by its reddish scales with contrasting greenish or yellow keels and by the laterally 1ribbed scales. The lateral rib is most often situated where the reddish and yellowish parts of the scale meet. Two varieties of C. reflexus, var. reflexus and var. fraternus, have been recognized (M. F. Denton 1978b). Both varieties were noted as intermingled in the North American and South American segments of the widely disjunct range of C. reflexus. Such variation does not seem significant at the varietal level (see G. C. Tucker 1994; G. C. Tucker and R. McVaugh 1993). (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Carex gracilis comprises diminutive plants with a delicate, arching habit and distinctive knoblike angles to the achenes. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 23. | FNA vol. 23. |
Parent taxa | Cyperaceae > Cyperus > subg. Pycnostachys | Cyperaceae > Cyperus > subg. Pycnostachys |
Sibling taxa | ||
Synonyms | C. arenicola, C. fraternus, C. pseudovegetus var. arenicola, C. reflexus var. fraternus | |
Name authority | Vahl: Enum. Pl. 2: 299. (1805) | R. Brown: Prodr., 213. (1810) |
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