Rhynchospora nitens |
Rhynchospora indianolensis |
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short-beak beaksedge, shortbeak bald-rush |
indianola beaksedge |
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Habit | Plants annual, cespitose or solitary, (10–)20–100 cm; rhizomes absent. | Plants perennial, cespitose, to 100 cm; rhizomes absent. |
Culms | erect, leafy, nearly terete or angled, manyribbed. |
stiffly erect or ascending, leafy-based, triangular, multiribbed. |
Leaves | ascending or erect, crowded toward culm base, shorter, more widely spaced distally, longest overtopping or equaling subtended inflorescences; principal blades flat, trigonous distally, 4–6 mm wide, apex attenuate, trigonous. |
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Inflorescences | terminal and axillary, clusters of corymbs 1–5, usually diffuse; leafy bracts exceeding proximal corymbs. |
terminal and axillary, compounds of fascicles, nearly umbellate; clusters hemispheric to nearly capitate, 1.5–2 cm wide; 1 cluster nearly sessile, others on slender rays to 7 cm, sometimes penultimate node with single cluster on peduncle 7–12 cm. |
Spikelets | dark brown, lanceoloid to ovoid, mostly 4–6(–8) mm, apex acute; fertile scales many, ovate, rounded-convex, 2–3.5 mm, apex acute, midrib mostly included, rarely forming apiculus. |
light redbrown, lanceoloid, 6–7 mm, apex acute; fertile scales lance-ovate, 5 mm, apex acute to blunt, midrib shortexcurrent or not. |
Flowers | perianth absent. |
perianth bristles 6, overtopping tubercle base, antrorsely barbellate. |
Fruits | 1–1.3(–1.5) mm, body dark brown, tumidly lenticular, nearly orbicular, 0.7–1 × 0.7–1 mm, margins strong, interrupted at tubercle base; surfaces irregularly transversely rugulose with wavy rows of vertical, linear, raised cells; tubercle depressed-triangular, 0.1–0.3 mm, capping fruit summit, base broadly 2lobed. |
1 per spikelet, (5.5–)6–7 mm; body obovoid, 3–4 × 2–2.5 mm, margins thick, crimped, surfaces level or concave, minutely pebbled; tubercle narrowly conic, 2grooved, 3–4 mm, base blunt, stout, capping fruit apex, tip barely exserted. |
Principal | midculm leaves often exceeding inflorescences; blades linear, proximally flattened, 1–5 mm wide, apex trigonous, tapering. |
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Rhynchospora nitens |
Rhynchospora indianolensis |
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Phenology | Fruiting summer–fall or all year. | Fruiting early summer–fall. |
Habitat | Moist to wet sands or peats of stream banks, pond shores, depressions in savannas, marshes | Silty shallows of pools, prairie swales, ditches |
Elevation | 0–100 m (0–300 ft) | 0–100 m (0–300 ft) |
Distribution |
AL; DE; FL; GA; IN; LA; MA; MI; MS; NC; NJ; NY; SC; TX; VA; Central America; West Indies
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TX |
Discussion | Rhynchospora indianolensis was considered by G. Kükenthal to be closely related to, if not the same as, the Cuban R. scutellata Grisebach but with fruit of different dimensions and sculpture. W. W. Thomas (1984) believed the two to be conspecific. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Source | FNA vol. 23, p. 217. | FNA vol. 23, p. 207. |
Parent taxa | ||
Sibling taxa | ||
Synonyms | Scirpus nitens, Isolepis nitens, Psilocarya nitens, Psilocarya rhynchosporoides | |
Name authority | (Vahl) A. Gray: Manual ed. 5, 568. (1867) | Small: Fl. S.E. U.S., 193, 1327. (1903) |
Web links |