Rhynchospora caduca |
Rhynchospora pusilla |
|
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anglestem beaksedge |
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Habit | Plants perennial, cespitose, 70–150 cm; rhizomes often present, short, scaly. | Plants perennial, densely cespitose, 15–50(–60) cm; rhizomes absent. |
Culms | erect or ascending, leafy, trigonous. |
erect or arching, leafy toward base, filiform, terete, wiry. |
Leaves | exceeded by culm; blades linear, proximally 4–7 mm wide, apex trigonous, tapering. |
overtopped by culm; blades linear to filiform, channeled, 0.3–0.5 mm wide, margins deeply involute, apex setaceous. |
Inflorescences | terminal and axillary; clusters 3–6, mostly dense, narrowly to broadly turbinate, branches ascending; leafy bracts exceeeding proximalmost inflorescences. |
spikelet clusters 1–2(–3), dense to open, narrowly to broadly turbinate; branches capillary, variously elongate; leafy bracts setaceous, equaling or exceeding clusters. |
Spikelets | rich brown, ovoid, (3–)4–5 mm, apex acuminate; fertile scales ovate, 2.5–3.5 mm, apex acuminate, midrib included or shortexcurrent. |
variously brown, ellipsoid, 2–3 mm, apex sharply acute; fertile scales ovate to nearly orbiculate, rounded, 1.2–1.8 mm, apiculate, convexcupulate, midrib slender, mostly included. |
Flowers | perianth bristles mostly 6, exceeding tubercle tip. |
perianth absent. |
Fruits | mostly 3–4 per spikelet, 2–2.2 mm; body brown on short pedicellar (to 0.3 mm) stalk, broadly obovoid, lenticular, 1.3–1.5 × 1–1.5 mm, surfaces transversely rugulose, vertically finely striate and rectangularalveolate; tubercle compressed, triangular acuminate, 0.5–0.8 mm, edges setulose. |
2–3 per spikelet, 0.7–0.9(–1) mm; body pale, obovoid-lenticular, (0.5–)0.6–0.9 × 0.4–0.5 mm, margin wirelike; surfaces transversely rugulose; tubercle buttonlike, depressed triangular, 0.05–0.1 mm, base lunate atop rounded fruit body. |
Rhynchospora caduca |
Rhynchospora pusilla |
|
Phenology | Fruiting summer–fall. | Fruiting summer–fall. |
Habitat | Low meadows, clearings, marshes, marsh borders, seeps, bog moats, savannas, ditches, pine flatwoods, swamps | Moist sands, peats and silts of low meadows, savannas, bogs, seeps, pond shores |
Elevation | 0–400 m (0–1300 ft) | 0–300 m (0–1000 ft) |
Distribution |
AL; AR; FL; GA; LA; MS; NC; OK; SC; TN; TX; VA
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AL; FL; GA; LA; MS; NC; SC; TX; Mexico; Central America; West Indies |
Discussion | Rhynchospora caduca has its closest relationships with the even more robust R. odorata Grisebach, on the one hand, and the swampinhabiting, more slender, and rhizomatous R. mixta Britton ex Small, on the other. Intergrades with R. odorata appear in Alabama and northwest Florida; intergrades with R. mixta appear where ranges overlap in both the Atlantic and Gulf coastal plains. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Source | FNA vol. 23, p. 223. | FNA vol. 23, p. 220. |
Parent taxa | Cyperaceae > Rhynchospora | Cyperaceae > Rhynchospora |
Sibling taxa | ||
Synonyms | Phaeocephalum caducum, R. patula | Phaeocephalum pusillum, R. intermixta |
Name authority | Elliott: Sketch Bot. S. Carolina 1: 62. (1816) | Chapman ex M. A. Curtis: Amer. J. Sci. Arts, ser. 2, 7: 409. (1849) |
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