Rhynchospora harperi |
Rhynchospora debilis |
|
---|---|---|
Harper's beaksedge |
savannah beaksedge |
|
Habit | Plants perennial, solitary or cespitose, 50–70 cm; rhizomes absent. | Plants perennial, cespitose, 20–45 cm; rhizomes absent. |
Culms | erect to excurved, leafybased, narrowly linear, ± terete. |
erect to arching or spreading, leafy, ± filiform, ± terete, stiff to rather lax. |
Leaves | shorter than culm; blades ascending, narrowly linear, proximally flat or margins slightly involute, 0.5–1(–2) mm wide, distally canaliculate, apex trigonous, tapering, subulate. |
exceeded by culm; blades linearfiliform, proximally shallowly concave, 1 mm, apex tapering, trigonous, blunt or broadly acute. |
Inflorescences | spikelet clusters 1–3, laterals 0–2, all turbinate to hemispheric, terminal internode usually excurved; leafy bracts setaceous, overtopping inflorescence. |
spikelet clusters 1–2, mostly compact, turbinate to hemispheric; leafy bracts setaceous, exceeding spikelet clusters. |
Spikelets | redbrown, lanceoloid, 5–7 mm, apex acute; fertile scales lanceolate, (2.5–)4–5 mm, apex acute to acuminate; midrib paralleled by several indistinct ribs, excurrent as short awns. |
dark redbrown, ovoid, 2–3 mm, apex acute; fertile scales obovate, 1.5–1.7(–2) mm, apex broadly rounded or retuse, midrib excurrent as cusp or mucro to 0.5 mm. |
Flowers | bristles 6, reaching from mid tubercle to beyond tip. |
bristles 6 or vestigial, rarely reaching fruit midbody, antrorsely barbellate. |
Fruits | 3(–4) per spikelet, 2.1–2.5 mm; stipe and receptacle 0.2–0.3 mm, sparsely setose and setulose; body glossy, brown with pale center, obovoid-lenticular, 1.1–1.5 × 1–1.1 mm, surfaces finely longitudinally lined, variably low papillatecancellate, also often transversely with wavy lines of dark dots; tubercle flattened, triangular-subulate, (0.8–)0.9–1(–1.1) mm, setulose-ciliate. |
1–2 per spikelet,1.7–2 mm; body brown with large pale center, lenticular, broadly obovoid to ± orbicular, 1.2–1.5 × 1.4–1.6 mm; tubercle flat, triangular, concave-sided, 0.4–0.6 mm, sometimes apiculate. |
Rhynchospora harperi |
Rhynchospora debilis |
|
Phenology | Fruiting summer–fall. | Fruiting late spring–fall. |
Habitat | Sands and peats of bogs, stream banks, edges of pineland savanna ponds, Hypericum ponds | Sands and peats in low, open fields, bogs, seeps, low pinelands, savannas, and ditch banks |
Elevation | 0–100 m (0–300 ft) | 0–200 m (0–700 ft) |
Distribution |
AL; DE; FL; GA; MD; MS; NC; SC; Central America (Belize)
|
AL; FL; GA; LA; MS; NC; SC; TX; VA |
Discussion | Rhynchospora harperi is most abundant in a very special habitat referred to here as the “Hypericum pond.” These are typically shallow ponds in pine savannas, frequently ringed by stands of Nyssa, Taxodium, Ilex, and Cyrilla, but most of the pond itself is dominated by one or more myriandrous shrubby Hypericum species. Here R. harperi is distinguished from other species by the often abrupt bend of its ultimate internode. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Rhynchospora debilis is very similar to R. wrightiana except it has smaller spikelet clusters and more depressed fruit tubercles. It is a common invader of cutover and bulldozed low pineland where it assumes a lowspreading habit, its many culms radiating from the common center much like spokes in a wheel. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 23, p. 233. | FNA vol. 23. |
Parent taxa | Cyperaceae > Rhynchospora | Cyperaceae > Rhynchospora |
Sibling taxa | ||
Synonyms | R. fascicularis var. harperi, R. leptorhyncha | R. fascicularis var. debilis |
Name authority | Small: Man. S.E. Fl., 182, 1503. (1933) | Gale: Rhodora 46: 194, plate 826, figs. 5A, B. (1944) |
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