Cyperus entrerianus |
Cyperus mutisii |
|
---|---|---|
woodrush flatsedge |
mutis' flatsedge |
|
Habit | Herbs, perennial, coarse; rhizomes (seldom collected) indurate, oblique, 5–12 mm wide, with fibrous brown floral scales, 1–5 cm. | Herbs, perennial, cespitose, rhizomatous. |
Culms | 1–3, trigonous to roundly trigonous, (30–)40–65(–95) cm × (1–)2–3 mm. |
trigonous, (20–)30–120 cm × 1.4–3.5 mm, glabrous or occasionally with scattered prickles on distal angles. |
Leaves | (1–)5–10, V-shaped, (10–)30–45(–70) cm × 3–7 mm. |
2–4(–6), inversely W-shaped, 10–60(–70) cm × (2–)4–13 mm, margins and midribs scabridulous or glabrous. |
Inflorescences | heads loosely to densely globose-ovoid, (6–)10–12(–20) mm diam.; rays 6–10(–12), 1–8(–12) cm; 2d order rays 1–4, 5–15(–23) mm; bracts (5–)6–8(–10), ascending at 45–60(–75)°, V-shaped, (5–)15–40(–55) cm × (1–)3–7 mm. |
spikes (1–)3–6, narrowly cylindric, 1–4(–6) cm × 5–11 mm; rays 0 or 3–6, 2–23 cm; bracts 5–8, ascending at ± 45°, inversely W-shaped, (4–) 14–40(–46) cm × 1–12 mm; rachilla deciduous, wings persistent, 0.3–0.5 mm wide. |
Spikelets | (1–)30–50(–65), greenish white, linear to broadly ellipsoid, flattened, 4–6.5 × 1.8–3.2 mm; floral scales (10–)16–20(–26), laterally clear, pale green, off-white, or light brown, medially green or light brown, laterally weakly 1-ribbed, medially 2-ribbed, basally 2-keeled, oblong-lanceolate, (1.2–)1.4–1.6(–1.8) × (0.7–)0.8–1 mm, apex acute, mucronate, distally glabrous or scabridulous. |
35–100, oblong-ellipsoid, ± terete, elliptic in cross section, 3–7 × (0.9–) 1.3–2 mm; distal spikelets spreading or ascending; floral scales persistent, 1–2(–5), appressed, becoming clear at maturity, laterally brownish to reddish brown, medially greenish, laterally 3–5-ribbed, medially 3-ribbed, often erose at maturity, ovate to elliptic, 2.2–3.2 × 1.5–2.1 mm, apex obtuse. |
Flowers | stamen 1; anthers ellipsoid, 0.6–0.7 mm, connective apex acute, 0.1–0.2 mm; styles 0.2–0.4 mm; stigmas 0.4–0.6 mm. |
anthers 0.6–0.8 mm; styles 0.4–0.8 mm; stigmas 1.2–2.2 mm. |
Achenes | brown, stipitate, ellipsoid to narrowly ellipsoid, broadly rounded or contracted basally, gradually tapered toward apex, 0.9–1.1 × 0.3–0.4 mm, stipe 0.1 mm, apex acute, surfaces finely reticulate. |
brown to reddish brown, sessile, broadly ellipsoid, slightly dorsiventrally flattened, 1.5–1.8 × 0.7–0.9(–1) mm, apex obtuse, apiculate, surfaces papillose to puncticulate. |
Cyperus entrerianus |
Cyperus mutisii |
|
Phenology | Fruiting summer. | Fruiting summer–fall (Jun–Nov). |
Habitat | Roadside ditches, marshes | Clearings in montane forests, canyons |
Elevation | 0–100 m (0–300 ft) | 500–1500 m (1600–4900 ft) |
Distribution |
AL; FL; GA; LA; MS; TX; Mexico; South America; Central America (Nicaragua) [Introduced in North America]
|
AZ; Mexico; Central America; South America |
Discussion | Cyperus entrerianus is a recent introduction in the southern United States (earliest collection from Pensacola County, Florida, Brinker 413, MO in 1941). It has been confused with C. luzulae. The species that Boeckeler had first described 50 years earlier was accepted by G. Kükenthal (1935–1936). Cyperus entrerianus was accepted as a variety of C. luzulae by A. B. Ayers (1946); M. F. Denton (1978b) considered C. entrerianus a synonym of C. luzulae, stating that the features of these two taxa merged so completely throughout their geographic ranges that C. entrerianus could not be given specific status. Cyperus luzulae in the strict sense does not extend northward to North America. Morphologic differences between Cyperus entrerianus and C. luzulae are as follows (G. C. Tucker 1994). Cyperus entrerianus has culms 40–75 cm; inflorescence bracts ascending at 45–60°; primary rays ascending at 45–60(–75)°; 2d order rays present; heads of spikelets loosely globose-ovoid, light greenish white to golden brown; rachilla dark red with stramineous scale scars; and scale apices acute. Cyperus luzulae has culms 20–40 cm; inflorescence bracts approximately horizontal; primary rays ascending at 15–30°; 2d order rays absent; heads of spikelets densely oblong to pyramidal, bright to dull white; rachilla green throughout; and scale apices rounded. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Cyperus mutisii is recognized by its cylindric spikes borne digitately at the ends of the rays and its short, plump spikelets. As spikelets mature, the floral scales, having erose margins contrasting with the brownish sides, beome useful distinguishing features. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 23. | FNA vol. 23, p. 189. |
Parent taxa | Cyperaceae > Cyperus > subg. Pycnostachys | Cyperaceae > Cyperus > subg. Cyperus |
Sibling taxa | ||
Synonyms | C. luzulae var. entrerianus | Mariscus mutisii, C. asper, C. compresso, C. ehrenbergianus, C. mutisii var. asper, C. mutisii var. contractus, C. mutisii var. semitribrachiatus, C. ochreatus, C. semitribrachiatus, Mariscus asper |
Name authority | Boeckeler: Flora 61: 139. (1878) | (Kunth) Andersson: Galapagos Veg., 53. (1854) |
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