The green links below add additional plants to the comparison table. Blue links lead to other Web sites.
enable glossary links

onespike beaksedge

Habit Plants perennial, solitary or cespitose, 50–60 cm; rhizomes absent. Plants perennial, densely cespitose, knottybased, 20–40 cm; rhizomes absent.
Culms

erect to ascending, narrowly linear, wandlike, terete, leafy proximal to middle.

leafy at base, filiform, wiry.

Leaves

erect to ascending;

blades proximally flat, 2.5–3.5 mm wide, apex tapering, tip abruptly blunt.

blades filiform, nearly reaching inflorescence tip or much shorter, to 0.3 mm thick, apex tapering.

Inflorescences

terminal, cluster of spikelets crowded, broadly turbinate to hemispheric, to 1.5 cm wide; leafy bracts linearsetaceous, slightly exceeding cluster.

spikelet clusters mostly 2–6, simple or reduced to 1 spikelet, often with 2 capillary branches, one divaricate or reflexed, 1 ascending; leafy bracts single per cluster, filiform, setaceous, with clusters appearing lateral to bracts.

Spikelets

orangebrown, lancefusiform, 6–7 mm, apex acuminate;

fertile scales lanceovate, 4–5 mm, apex acuminate with excurved awn to 1 mm.

pale redbrown, ellipsoidlanceoloid, 5–6(–8) mm, apex acute to acuminate;

fertile scales narrowly ovate, 3–5(–6) mm, apex acute, midrib included or shortexcurrent.

Flowers

bristles 3–4, some reaching tubercle tip, antrorsely barbellate.

perianth bristles 6, not reaching past fruit midbody, stubby, plumose to near tip.

Fruits

1–2 per spikelet, 2–2.1 mm;

body brown with paler center, obovoidlenticular, 1.5–1.7 × 1.2–1.3 mm, margins flowing to tubercle;

surfaces finely transversely striate with minute pits;

tubercle lowtriangular, 0.3–0.5 mm.

3–8 per spikelet, 2–2.5 mm;

body light brown to brown, ellipsoid-obovoid, tumidly lenticular, 1.5–2 × 1.6–1.7 mm;

surfaces faintly, interruptedly crossrugulose, apically indented under tubercle;

tubercle lowconic, 0.5 mm, base flaring, circular.

Rhynchospora solitaria

Rhynchospora breviseta

Phenology Fruiting summer–fall. Fruiting spring–summer.
Habitat Sandy peat of depressions in pine flatwoods savannas, edges of hillside bogs Moist to wet sands or peats of bogs, depressions in savannas, open pinelands, pond shores
Elevation 0–200 m (0–700 ft) 0–200 m (0–700 ft)
Distribution
from FNA
GA
[BONAP county map]
from FNA
AL; FL; GA; LA; MS; NC; SC; VA; West Indies
Discussion

Of conservation concern.

Rhynchospora solitaria appears to be the least common North American species of Rhynchospora with two of the five given localities apparently lost. The name “solitaria” is deceptive; the plants sometimes form small tufts of culms. The most distinctive feature in the field is the attractive orangebrown color of the narrow, acuminate, bristlescaled spikelets.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Rhynchospora breviseta is sympatric with R. oligantha over much of its range; intergrades have not been seen.

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Source FNA vol. 23, p. 238. FNA vol. 23.
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. 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. stenophylla, R. thornei, R. torreyana, R. tracyi, R. wrightiana
R. alba, R. baldwinii, R. brachychaeta, 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. 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 R. oligantha var. breviseta
Name authority R. M. Harper: Bull. Torrey Bot. Club 28: 468. (1901) (Gale) Channell: Rhodora 58: 336. (1956)
Web links