Rhynchospora caduca |
Rhynchospora curtissii |
|
---|---|---|
anglestem beaksedge |
Curtiss' beaksedge |
|
Habit | Plants perennial, cespitose, 70–150 cm; rhizomes often present, short, scaly. | Plants perennial, densely cespitose, 10–30 cm; rhizomes absent. |
Culms | erect or ascending, leafy, trigonous. |
lax, erect to excurved, leafy toward base, filiform. |
Leaves | exceeded by culm; blades linear, proximally 4–7 mm wide, apex trigonous, tapering. |
overtopped by scape; blades filiform, distally flattened, channeled, tapering, to 1 mm wide, margins strongly involute, apex blunt. |
Inflorescences | terminal and axillary; clusters 3–6, mostly dense, narrowly to broadly turbinate, branches ascending; leafy bracts exceeeding proximalmost inflorescences. |
spikelet clusters 1–3, laterals widely spaced, all narrowly turbinate, ellipsoid, or ovoid; leafy bracts setaceous, overtopping proximal clusters, often overtopped by terminal ones. |
Spikelets | rich brown, ovoid, (3–)4–5 mm, apex acuminate; fertile scales ovate, 2.5–3.5 mm, apex acuminate, midrib included or shortexcurrent. |
erect or ascending, redbrown, lanciform, mostly 4.5–5 mm, apex acute; fertile scales lanceolate, (3–)4–4.5 mm, apex acute, apiculate. |
Flowers | perianth bristles mostly 6, exceeding tubercle tip. |
perianth absent. |
Fruits | mostly 3–4 per spikelet, 2–2.2 mm; body brown on short pedicellar (to 0.3 mm) stalk, broadly obovoid, lenticular, 1.3–1.5 × 1–1.5 mm, surfaces transversely rugulose, vertically finely striate and rectangularalveolate; tubercle compressed, triangular acuminate, 0.5–0.8 mm, edges setulose. |
2–3(–5) per spikelet; stipe and receptacle 0.1–0.2(–0.3) mm, setose; body brown with pale glassy center, narrowly obovoidellipsoid, lenticular, 1.2–1.5 mm, margins narrow, flowing to tubercle; surfaces very finely lined longitudinally, transversely with wavy lines of tiny pits; tubercle narrowly triangular or slightly concavesided, flattened, 0.7–1.2(–1.5) mm. |
Rhynchospora caduca |
Rhynchospora curtissii |
|
Phenology | Fruiting summer–fall. | Fruiting summer–fall. |
Habitat | Low meadows, clearings, marshes, marsh borders, seeps, bog moats, savannas, ditches, pine flatwoods, swamps | Sands and peats of bogs, pineland pond shores, seeps, and low moist savannas |
Elevation | 0–400 m (0–1300 ft) | 0–100 m (0–300 ft) |
Distribution |
AL; AR; FL; GA; LA; MS; NC; OK; SC; TN; TX; VA
|
AL; FL; MS |
Discussion | Rhynchospora caduca has its closest relationships with the even more robust R. odorata Grisebach, on the one hand, and the swampinhabiting, more slender, and rhizomatous R. mixta Britton ex Small, on the other. Intergrades with R. odorata appear in Alabama and northwest Florida; intergrades with R. mixta appear where ranges overlap in both the Atlantic and Gulf coastal plains. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
|
Source | FNA vol. 23, p. 223. | FNA vol. 23, p. 234. |
Parent taxa | Cyperaceae > Rhynchospora | Cyperaceae > Rhynchospora |
Sibling taxa | ||
Synonyms | Phaeocephalum caducum, R. patula | Phaeocephalum curtissii, R. filifolia var. ellipsoidea |
Name authority | Elliott: Sketch Bot. S. Carolina 1: 62. (1816) | Britton: in J. K. Small, Fl. S.E. U.S., 195, 1327. (1903) |
Web links |