Rhynchospora fascicularis |
Rhynchospora brachychaeta |
|
---|---|---|
fascicled beaksedge |
West Indian beaksedge |
|
Habit | Plants perennial, cespitose, 100–150 cm; rhizomes absent. | Plants perennial, densely cespitose, 20–50 cm; rhizomes absent. |
Culms | erect to excurvedascending, narrowly linear to ± filiform, terete to obscurely trigonous, leafy, densely so toward base, stiff to rather lax. |
erect to excurved, lax, filiform, leafy, ± terete. |
Leaves | overtopped by culm; blades linear, ascending, proximally flat, 1–4 mm wide, apex trigonous, subulate, tapering gradually. |
exceeded by culm, ascending; blades filiform, ± terete, margins strongly involute, apex trigonous, sulcate, tapering. |
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 mostly 2–3, sparse to dense, oblong to broadly or narrowly turbinate; leafy bracts setaceous, 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. |
pale redbrown, lanceoloid, 3–3.5 mm, apex acute; fertile scales mostly elliptic, 2–2.5 mm, apex acute, sometimes apiculate. |
Flowers | bristles 5–6, from rudimentary to reaching tubercle tip, or (rarely) beyond, antrorsely barbellate. |
bristles mere nubs or 1–2, to 0.3 mm. |
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 per spikelet, 1.5–1.6 mm; body redbrown with pale center, lenticular, broadly obovoid to orbicular, margins pale, narrow, flowing to tubercle; surfaces smoothish, or faintly cancellate; tubercle flattened, triangularsubulate, 0.3–0.5 mm. |
Rhynchospora fascicularis |
Rhynchospora brachychaeta |
|
Phenology | Fruiting late spring–fall or all year (south). | Fruiting late spring–fall. |
Habitat | Sands and peats of interdunal swales, depressions in savannas, open flatwoods, and seep-bog edges | Moist sandy peaty substrates in savannas or savanna bog transition, ditches, and moist, disturbed areas |
Elevation | 0–100 m (0–300 ft) | |
Distribution |
AL; FL; GA; LA; MS; NC; SC; TX; VA; Central America; Bermuda
|
AL; FL; MS; Central America; West Indies |
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.) |
Rhynchospora brachychaeta is quite possibly adventive; most of its localities in the flora are in disturbed areas near the coast. It is similar to the widespread native R. chapmanii, from which it is distinguished by its more numerous spikelet clusters, the darker spikelets, the achene faces brown with pale centers (rather than pale with brown ends), and the relatively more developed perianth. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 23, p. 239. | FNA vol. 23, p. 235. |
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 brachychaetum, R. blauneri, R. chapmanii, R. pallida, R. pallida |
Name authority | (Michaux) Vahl: Enum. Pl. 2: 234. (1805) | C. Wright: Anales Real Acad. Ci. Méd. Fís. Nat. Habana 8: 85. (1873) |
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