Cyperus reflexus |
Cyperus lancastriensis |
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bentawn flatsedge |
manyflower flatsedge, Porter's sedge |
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Habit | Herbs, perennial, cespitose; rhizomes elongate, scaly, 2–3 mm wide. | Herbs, perennial, cespitose, with inconspicuous, short rhizomes scarcely visible between culm bases. |
Culms | roundly trigonous to terete, 30–80 cm × 1–1.6 mm, glabrous. |
basally cormlike, trigonous, (10–)20–80 cm × 1–3 mm, glabrous. |
Leaves | 1–6, 10–40 cm, glabrous or essentially so. |
inversely W-shaped, 20–70 cm × 5–11 mm, adaxial surface, margins minutely scabridulous. |
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. |
spikes densely ellipsoid to obovoid, 2.5–4.3 × 1.5–3 cm; rays 5–10, 4–20 cm, glabrous; rachis 7–14 mm; bracts 3–8, horizontal to ascending at 45°, flat, 5–35 cm × 2.5–6 mm; rachilla persistent, wings 0.5 mm wide. |
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). |
50–90, linear-lanceoloid to linear-subulate, ± terete-quadrangular, (11–)12–13(–15) × 1.1–1.6 mm; distal spikelet spreading or ascending; floral scales persistent, 3–6(–8), appressed, whitish green or often yellow-tinted, sometimes reddish striate, laterally 4-ribbed, ovate-lanceolate, (3.9–)4.2–4.6(–4.8) × 1.6–2 mm. |
Flowers | stamen 1; anthers 0.6–1 mm; styles 0.3–0.5 mm; stigmas 0.3–0.6 mm. |
anthers 0.7–1 mm; styles 1–1.5 mm; stigmas 2–3 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. |
yellowish brown to brown, ± stipitate, conspicuously falcate, 3–4 times long as wide, oblong, 2.2–2.6 × 0.6–0.7 mm, apex obtuse, surfaces puncticulate. |
Cyperus reflexus |
Cyperus lancastriensis |
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Phenology | Fruiting late spring–fall (May–Oct). | Fruiting summer (Jul–Aug). |
Habitat | Muddy soils or shallow waters | Disturbed, sunny or partly shaded places in mesic or dry-mesic soils, often on riverbanks and flood plains |
Elevation | 0–200 m (0–700 ft) | 0–800 m (0–2600 ft) |
Distribution |
FL; LA; OK; TX; Mexico; Central America (Costa Rica) |
AL; AR; DC; DE; FL; GA; KY; MD; MO; NC; NJ; OH; PA; SC; TN; VA; WV
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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.) |
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Source | FNA vol. 23. | FNA vol. 23. |
Parent taxa | Cyperaceae > Cyperus > subg. Pycnostachys | Cyperaceae > Cyperus > subg. Cyperus |
Sibling taxa | ||
Synonyms | C. arenicola, C. fraternus, C. pseudovegetus var. arenicola, C. reflexus var. fraternus | C. refractus var. lancastriensis, Mariscus lancastriensis |
Name authority | Vahl: Enum. Pl. 2: 299. (1805) | Porter: in A. Gray, Manual ed. 5 issue 6, 555. (1867) |
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