Rhynchospora perplexa |
Rhynchospora elliottii |
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pineland beaksedge |
Elliott's beaksedge |
|
Habit | Plants perennial, cespitose, 50–110 cm; rhizomes absent. | Plants perennial, cespitose, 80–150 cm; rhizomes absent. |
Culms | lax, often excurved, slender, ± terete or trigonous. |
erect with arching tops, leafy, obscurely trigonous, slender. |
Leaves | ascending, exceeded by culm; blades linear, proximally flat, 1.5–2.5 mm wide, apex trigonous, subulate, tapering. |
overtopped by inflorescence; blades linear, proximally flat, 3–5 mm wide, apex trigonous, subulate, tapering. |
Inflorescences | clusters 3–4, widely spaced, narrowly, compactly, or diffusely turbinate; leafy bracts exceeding proximal clusters. |
spikelet clusters mostly 4–6, various in shape and crowding, narrowly to broadly turbinate; peduncles erect, branches slender, ascending; leafy bracts exceeding all but most distal clusters. |
Spikelets | deep redbrown, ovoid to broadly ellipsoid, 2–3 mm, apex acute to acuminate; fertile scales broadly elliptic to obovate or orbiculate, 1.4–2(–2.5) mm, apex rounded to notched, midrib shortexcurrent. |
redbrown, broadly ellipsoid, (1.5–)2–3(–3.5) mm, apex acute; fertile scales broadly ovate, 2–3 mm, midrib excurrent as apiculus or awn. |
Flowers | perianth bristles 0–3, vestigial when present. |
perianth bristles 6, mostly spreading, usually exceeding tubercle, antrorsely barbellate. |
Fruits | 2–4 per spikelet, 1.5 mm; body pale brown to brown, strongly flattened, orbicular to broadly obovoid, 1–1.3 × 0.9–1.2 mm, surfaces sharply transversely wavyrugose, intervals finely vertically striate with rows of linearrectangular alveolae; tubercle depressed, triangular, flattened, 0.2–0.3 mm, base lunate. |
2–3(–4) per spikelet, 1.5(–1.7) mm; body pale brown to brown, strongly flattened, obovoidorbicular, 1–1.2 × 0.8–1.1; surfaces transversely wavyrugose, intervals vertically striate with very narrowly rectangular alveolae; tubercle flat, triangular or concavely triangular, 0.3–0.5(–0.7) mm. |
Rhynchospora perplexa |
Rhynchospora elliottii |
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Phenology | Fruiting late spring–fall or all year (south). | Fruiting late spring–fall or all year (south). |
Habitat | Sands and peats of pond and lakeshores, depressions in savannas and flatwoods, or seeps | Sands and peats of bogs, shorelines, interdunal swales, savannas, and pine flatwoods |
Elevation | 0–400 m (0–1300 ft) | 0–200 m (0–700 ft) |
Distribution |
AL; FL; GA; LA; MS; NC; SC; TN; TX; VA; Central America; West Indies (Cuba, Dominican Republic) |
AL; FL; GA; LA; MS; NC; SC; TX |
Discussion | In habit and in shape, size, and color of spikelet, Rhynchospora perplexa strongly resembles R. microcarpa, a species with which it is commonly associated in the Coastal Plain. An examination of the fruit shows those of R. perplexa to be flattened, with fewer and much coarser transverse ridges, the intervals with very narrow vertical alveolae. The perianth in most instances is absent or rudimentary. Fruit of R. microcarpa is biconvex with more transverse ridges (eight or more), the intervals more coarsely alveolate; its perianth bristles are six, evident, extending at least halfway up the fruit body. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Rhynchospora elliottii is most likely to be confused in the field with its frequent associates R. microcarpa and R. perplexa. Most of the time it can be distinguished from both by its taller, coarser, broader-leaved habit and by its distinctly redder spikelets. Inspection of the fruit reveals the spreading character of the perianth bristles, these usually a length level with the tubercle tip or longer and giving the whole structure the appearance of an unengorged tick. (Discussion copyrighted by Flora of North America; reprinted with permission.) |
Source | FNA vol. 23, p. 229. | FNA vol. 23, p. 229. |
Parent taxa | ||
Sibling taxa | ||
Synonyms | Phaeocephalum perplexum | Phaeocephalum schoenoides, R. multiflora, R. schoenoides, Scirpus schoenoides |
Name authority | Britton: in J. K. Small, Fl. S.E. U.S., 197, 1328. (1903) | A. Dietrich: Sp. Pl. 2: 69. (1833) |
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