Rhynchospora pusilla |
Rhynchospora floridensis |
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Florida whitetop |
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Habit | Plants perennial, densely cespitose, 15–50(–60) cm; rhizomes absent. | Plants perennial, cespitose, 20–50 cm, wiry; rhizomes absent. |
Culms | erect or arching, leafy toward base, filiform, terete, wiry. |
erect to spreading, leafybased; scapes nearly filiform, nearly trigonous, few ribbed. |
Leaves | overtopped by culm; blades linear to filiform, channeled, 0.3–0.5 mm wide, margins deeply involute, apex setaceous. |
spreading to erect, exceeded by scape; blades filiform to linear, proximally flat or involute, becoming involute, 0.4–2 mm wide, apex tapering, trigonous. |
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, solitary, headlike, dense, white, leafyinvolucrate, 0.5–1 cm wide; involucral bracts 3–6, spreading to recurved, whitebased, greentipped, narrowly linear, longest bract elongatesubulate, 4–8 cm × 2–5 mm. |
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. |
white, ovoid, 4–6 mm; scales several, boatshaped, basal ones with ciliolate keel, fertile ones 3–3.8 mm. |
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. |
1–1.2 mm; body yellow to black, nearly orbicular, tumidly lenticular, 0.8–1 × 0.6–0.7(–1) mm; surface lattices shortlinear, vertical in fine undulating rows, with ends raised to rounded, transverse rugulosities; tubercle lowtriangular, lunate, 0.2–0.3 mm, apex acute, blunt or apiculate. |
Rhynchospora pusilla |
Rhynchospora floridensis |
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Phenology | Fruiting summer–fall. | Fruiting spring–fall, or all year. |
Habitat | Moist sands, peats and silts of low meadows, savannas, bogs, seeps, pond shores | Moist open areas over reef limestones, rocky pine savanna |
Elevation | 0–300 m (0–1000 ft) | 0–50 m (0–200 ft) |
Distribution |
AL; FL; GA; LA; MS; NC; SC; TX; Mexico; Central America; West Indies |
FL; Mexico (Chiapas, Yucatán); West Indies (Bahamas); Central America (Belize) |
Discussion | Rhynchospora floridensis is much like R. colorata, with which it is often associated; it can be easily distinguished by its strictly cespitose habit and its ciliolate spikelet scale keels. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
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Source | FNA vol. 23, p. 220. | FNA vol. 23, p. 216. |
Parent taxa | Cyperaceae > Rhynchospora | Cyperaceae > Rhynchospora |
Sibling taxa | ||
Synonyms | Phaeocephalum pusillum, R. intermixta | Dichromena floridensis |
Name authority | Chapman ex M. A. Curtis: Amer. J. Sci. Arts, ser. 2, 7: 409. (1849) | (Britton) H. Pfeiffer: Repert. Spec. Nov. Regni Veg. 49: 82. (1940) |
Web links |