Rhynchospora pusilla |
Rhynchospora capitellata |
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brownish beak-rush, brownish beaksedge, capitate beak rush, rhynchospore à petites têtes |
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Habit | Plants perennial, densely cespitose, 15–50(–60) cm; rhizomes absent. | Plants perennial, cespitose, 20–100 cm; rhizomes absent. |
Culms | erect or arching, leafy toward base, filiform, terete, wiry. |
arching-ascending, leafy, obtusely trigonous, slender; principal leaves overtopped by inflorescence; blades flat, to 3 mm, apex tapering, trigonous. |
Leaves | overtopped by culm; blades linear to filiform, channeled, 0.3–0.5 mm wide, margins deeply involute, apex setaceous. |
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Inflorescences | spikelet clusters 1–2(–3), dense to open, narrowly to broadly turbinate; branches capillary, variously elongate; leafy bracts setaceous, equaling or exceeding clusters. |
terminal and axillary, clusters 1–5 or more, compact, turbinate or hemispheric, 1–1.5 cm wide; peduncles progressively shorter distally on culm; bracteal leaves mostly exceeding subtended compounds. |
Spikelets | 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. |
rich deep brown, rarely pale brown, lanceellipsoid, 3.5–4(–5) mm; fertile scale elliptic, 2.7–3 mm, apex acute or rounded, midrib shortexcurrent or not. |
Flowers | perianth absent. |
perianth absent. |
Fruits | 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. |
(1–)2–3(–5) per spikelet, (2–)2.5–3 mm; body redbrown with pale central disc, stipitate, lenticular, obovoid, 1.2–1.5 × 0.7–1(–1.2) mm, margins pale, wirelike, surfaces slick; tubercle triangular-subulate, (0.8–)1–1.2(–1.6) mm. |
Rhynchospora pusilla |
Rhynchospora capitellata |
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Phenology | Fruiting summer–fall. | Fruiting summer–fall. |
Habitat | Moist sands, peats and silts of low meadows, savannas, bogs, seeps, pond shores | Moist to wet meadows, swales, seeps, stream banks, flatwoods, fens, and bogs |
Elevation | 0–300 m (0–1000 ft) | 0–1600 m (0–5200 ft) |
Distribution |
AL; FL; GA; LA; MS; NC; SC; TX; Mexico; Central America; West Indies |
AL; AR; CA; CT; DC; DE; FL; GA; IL; IN; KS; KY; LA; MA; MD; ME; MI; MN; MO; MS; NC; NH; NJ; NY; OH; OR; PA; RI; SC; TN; TX; VA; VT; WI; WV; NB; NS; ON; QC
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Discussion | Rhynchospora capitellata occurs infrequently in the lower Gulf coastal plain (in Florida, only north) and intergrades with R. glomerata. Forms with antrorsely barbellate bristles are referred to forma controversa (S. F. Blake) Gale; those with smooth bristles are named forma discutiens (C. B. Clarke) Gale (S. Gale 1944). Occasional forms with trigonous fruits occur. Bruce Sorrie (pers. comm.) believes that many of the southern coastal plain records for Rhynchospora capitellata are based on examples of a neglected taxon, R. leptocarpa (Chapman) Small (J. K. Small 1933), and he wishes to reinstate it. Occurring in semi-shady moist sites in steepheads, or from seeps and shallows along blackwater streams, the plants are mostly distinguished by the tall, lax habit; the many distant, small clusters of light brown or tan spikelets; and the softer, more lax foliage. Measures of spikelets, fertile scales, perianth, achenes, and fruit tubercles show a strong overlap with those of southern examples of R. capitellata. The long, lax culm habit, the softer and paler foliage, and the paler spikelets could well be ecologic responses, or the plants could indeed represent a geographic variant. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Source | FNA vol. 23, p. 220. | FNA vol. 23, p. 210. |
Parent taxa | Cyperaceae > Rhynchospora | Cyperaceae > Rhynchospora |
Sibling taxa | ||
Synonyms | Phaeocephalum pusillum, R. intermixta | Schoenus capitellatus, Phaeocephalum glomeratum var. minus, R. capitellata var. leptocarpa, R. capitellata var. minor, R. glomerata var. minor, R. leptocarpa |
Name authority | Chapman ex M. A. Curtis: Amer. J. Sci. Arts, ser. 2, 7: 409. (1849) | (Michaux) Vahl: Enum. Pl. 2: 235. (1805) |
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