Rhynchospora latifolia |
Rhynchospora divergens |
|
---|---|---|
sandswamp whitetop |
spreading beaksedge |
|
Habit | Plants perennial, cespitose or solitary, to 100 cm; rhizomes scaly, 3–4 mm thick. | Plants perennial, densely cespitose, 10–60 cm; rhizomes absent. |
Culms | arching or erect, leafy-based, distally wandlike, terete, multiribbed. |
erect or spreadingarching, linearfiliform, terete, leafy toward base. |
Leaves | ascending to spreading, overtopped by scape; blades linear, proximally flat, 2.5–5 mm wide, apex subulate, trigonous. |
overtopped by culm; blades ascending, filiform, 0.3–0.5 mm wide, margins deeply involute, then channeled, apex trigonous, setaceous. |
Inflorescences | terminal, headlike clusters of spikelets, clusters dense, leafy-involucrate; involucral bracts several, spreading to downcurved, longest 6–13 cm × 5–10 mm, mostly white to midbract, then green, abruptly narrowly linear. |
spikelet clusters 1–2(–4), dense(–open), narrowly to broadly turbinate; branches capillary, variously elongate; leafy bracts setaceous, proximal exceeding clusters. |
Spikelets | white, ovoid, 5–7 mm; fertile scales boatshaped, sharply curved-keeled, 5 mm, apex acute. |
brownish, lanceellipsoid to fusiform, 2–2.5(–3) mm, apex acute; fertile scales broadly elliptic, 1.5 mm, apex narrowly rounded to broadly acute, apiculate, convexcupulate, midrib narrow, shortexcurrent or included. |
Flowers | perianth absent. |
perianth absent. |
Fruits | several per spikelet, 1.5–2 mm; body yellowish to deep brown, tumidly lenticular, broadly obovoid to orbicular or oblate, 1.5 mm, widest at or toward midbody, margins flowing to tubercle; surfaces with many fine rows of vertical shallow lattices, their contiguous ends making transverse rows of papillae; tubercle crescent-based, depressed-triangular, 0.5 mm, apex acute. |
1–3 or more per spikelet, (0.6–)0.7–0.9(–1) mm; body pale, glassy, obovoidlenticular, 0.6–0.7 × 0.4–0.5 mm, margins narrow, wirelike; surfaces finely striate, very finely reticulate; tubercle button depressedtriangular or patelliform, 0.1–0.15 mm, apiculate. |
2n | = 12. |
|
Rhynchospora latifolia |
Rhynchospora divergens |
|
Phenology | Fruiting late spring–summer. | Fruiting summer–fall or all year (south). |
Habitat | Sands and peats of bogs in pine savannas and flatwoods | Moist sands, peats, silts or clays of low meadows, bogs, flatwoods, sometimes seeps over calcareous rock |
Elevation | 0–200 m (0–700 ft) | 0–300 m (0–1000 ft) |
Distribution |
AL; FL; GA; LA; MS; NC; SC; TX
|
AL; FL; GA; LA; MS; NC; SC; TX; Central America; West Indies (Bahamas, Cuba, Dominican Republic) |
Discussion | A specimen collected near Tullahoma, Tennessee, reported as Dichromena latifolia (A. Gattinger 1901), was later destroyed by fire. I did not see the specimen, nor was a description of it published. Because extant populations of the similar Rhynchospora colorata are just over the border in Alabama, that species is likely to have been the one found by Gattinger. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
|
Source | FNA vol. 23. | FNA vol. 23, p. 220. |
Parent taxa | Cyperaceae > Rhynchospora | Cyperaceae > Rhynchospora |
Sibling taxa | ||
Synonyms | Dichromena latifolia, R. stellata var. latifolia | |
Name authority | (Baldwin) W. W. Thomas: Mem. New York Bot. Gard. 37: 86. (1984) | Chapman ex M. A. Curtis: Amer. J. Sci. Arts, ser. 2, 7: 409. (1849) |
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