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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
from FNA
AL; FL; GA; LA; MS; NC; SC; TX
[WildflowerSearch map]
[BONAP county map]
from FNA
AL; FL; GA; LA; MS; NC; SC; TX; Central America; West Indies (Bahamas, Cuba, Dominican Republic)
[BONAP county map]
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
R. alba, R. baldwinii, R. brachychaeta, R. breviseta, R. caduca, R. californica, R. capillacea, R. capitellata, R. careyana, R. cephalantha, R. chalarocephala, R. chapmanii, R. ciliaris, R. colorata, R. compressa, R. corniculata, R. crinipes, R. curtissii, R. debilis, R. decurrens, R. divergens, R. elliottii, R. eximia, R. fascicularis, R. fernaldii, R. filifolia, R. floridensis, R. fusca, R. globularis, R. glomerata, R. gracilenta, R. grayi, R. harperi, R. harveyi, R. indianolensis, R. inexpansa, R. inundata, R. knieskernii, R. kunthii, R. macra, R. macrostachya, R. megalocarpa, R. megaplumosa, R. microcarpa, R. microcephala, R. miliacea, R. mixta, R. nitens, R. nivea, R. odorata, R. oligantha, R. pallida, R. perplexa, R. pineticola, R. pleiantha, R. plumosa, R. punctata, R. pusilla, R. rariflora, R. recognita, R. scirpoides, R. solitaria, R. stenophylla, R. thornei, R. torreyana, R. tracyi, R. wrightiana
R. alba, R. baldwinii, R. brachychaeta, R. breviseta, R. caduca, R. californica, R. capillacea, R. capitellata, R. careyana, R. cephalantha, R. chalarocephala, R. chapmanii, R. ciliaris, R. colorata, R. compressa, R. corniculata, R. crinipes, R. curtissii, R. debilis, R. decurrens, R. elliottii, R. eximia, R. fascicularis, R. fernaldii, R. filifolia, R. floridensis, R. fusca, R. globularis, R. glomerata, R. gracilenta, R. grayi, R. harperi, R. harveyi, R. indianolensis, R. inexpansa, R. inundata, R. knieskernii, R. kunthii, R. latifolia, R. macra, R. macrostachya, R. megalocarpa, R. megaplumosa, R. microcarpa, R. microcephala, R. miliacea, R. mixta, R. nitens, R. nivea, R. odorata, R. oligantha, R. pallida, R. perplexa, R. pineticola, R. pleiantha, R. plumosa, R. punctata, R. pusilla, R. rariflora, R. recognita, R. scirpoides, R. solitaria, R. stenophylla, R. thornei, R. torreyana, R. tracyi, R. wrightiana
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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