Rhynchospora fascicularis |
Rhynchospora mixta |
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fascicled beaksedge |
mingled beaksedge |
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Habit | Plants perennial, cespitose, 100–150 cm; rhizomes absent. | Plants perennial, cespitose, 80–100 cm; rhizomes stoloniferous, often elongate, slender, to 1 dm or more. |
Culms | erect to excurvedascending, narrowly linear to ± filiform, terete to obscurely trigonous, leafy, densely so toward base, stiff to rather lax. |
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Leaves | overtopped by culm; blades linear, ascending, proximally flat, 1–4 mm wide, apex trigonous, subulate, tapering gradually. |
exceeded by culm; blades lax, linear, proximally flat, 3–5 mm wide, apex abruptly narrowed, trigonous, subulate. |
Inflorescences | spikelet clusters 1–3(–4), proximal mostly widely spaced, dense, broadly turbinate to hemispheric, to 2 cm broad; leafy bracts subulate, exceeding proximal spikelets, slightly or not exceeding most distal clusters. |
spikelet clusters 4–6, mostly widely spaced; peduncles erect or ascending, slender; branches capillary, divaricate, or widely spreading, to small clusters of 1–few spikelets; leafy bracts mostly exceeding clusters. |
Spikelets | redbrown, narrowly ovoid, (3–)3.5–5 mm, apex acute; fertile scales ovate, 3–3.5(–4) mm, apex acute, mostly with cusp or mucro 0.5–1 mm. |
lanceovoid, 3–4(–6) mm, apex acute to acuminate; fertile scales elliptic, 2.5 mm, apex acute, midrib forming mucro or awn. |
Flowers | bristles 5–6, from rudimentary to reaching tubercle tip, or (rarely) beyond, antrorsely barbellate. |
perianth bristles 6, overtopping tubercle, antrorsely barbellate. |
Fruits | 1–3 per spikelet, (1.5–)2–2.2(–2.5) mm; body dark brown with pale center, lenticular, broadly ellipsoid to ± orbicular, (1.3–)1.5–1.7(–1.9) × 1–1.5 mm, margins pale, narrow or narrowly rounded, flowing to tubercle; surfaces dull, minutely longitudinally striate; tubercle compressed, triangular to triangularsubulate, 0.5–0.7(–0.9) mm. |
mostly 2–4(–several) per spikelet, (1.5–)1.8–2(–2.1); body greenish or pale brown, broadly ellipsoid to narrowly obovoid, lenticular, 1.2–1.5 × 1–1.2 mm; surfaces transversely finely wavy-rugulose, intervals vertically striatealveolate, or alveolae isodiametric; tubercle flat, triangular-subulate, 0.5–0.6(–0.8) mm. |
Rhynchospora fascicularis |
Rhynchospora mixta |
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Phenology | Fruiting late spring–fall or all year (south). | Fruiting summer–fall. |
Habitat | Sands and peats of interdunal swales, depressions in savannas, open flatwoods, and seep-bog edges | Sandy silts of swamp forests and environs |
Elevation | 0–100 m (0–300 ft) | 0–200 m (0–700 ft) |
Distribution |
AL; FL; GA; LA; MS; NC; SC; TX; VA; Central America; Bermuda
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AL; FL; GA; LA; MS; NC; SC; TX
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Discussion | In her revision, S. Gale (1944) treated var. distans as the more slender version of the species, one with a smaller inflorescence, more distinctly margined fruit body, and consistently elongate perianth bristles. All those character states appear to vary independently over the total range of the species. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Some extremes of Rhynchospora caduca with more diffuse inflorescences are mistaken for R. mixta, particularly those in which ultimate inflorescence branches lead to solitary spikelets. In those rare instances one should find a somewhat larger spikelet and a broader fruit than is typical for R. mixta. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 23, p. 239. | FNA vol. 23, p. 224. |
Parent taxa | Cyperaceae > Rhynchospora | Cyperaceae > Rhynchospora |
Sibling taxa | ||
Synonyms | Schoenus fascicularis, Dichromena distans, Phaeocephalum fasciculare, Phaeocephalum distans, R. distans, R. distans var. fascicularis, R. dommucensis, R. fascicularis var. distans, Schoenus distans | Phaeocephalum proliferum, R. prolifera |
Name authority | (Michaux) Vahl: Enum. Pl. 2: 234. (1805) | Britton: in J. K. Small, Fl. S.E. U.S., 197, 1328. (1903) |
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