Rhynchospora megaplumosa

E. L. Bridges & Orzell

Lundellia 3: 20, fig. 1. 2000.

Treatment appears in FNA Volume 23. Treatment on page 218. Mentioned on page 217, 219.
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Plants perennial, cespitose, 20–90 cm, base pale-brown to dark-brown; rhizomes absent or compact, knotty, scaly. Culms erect to arching-ascending, leafy, wandlike. Leaves mostly basal, few and increasingly distant upculm, shorter than scape; blades narrowly linear, concave proximally, (1–) 2–3 mm wide, tapering and increasingly involute-sulcate proximally, margins scabrid, apex triquetrous, tip narrow but blunt. Inflorescences: clusters 1 (–2), if 2 then close together, dense, broadly turbinate to hemispheric; primary leafy bracts linear, stiff, exceeding clusters. Spikelets light-brown, narrowly lanceoloid, 8–10 mm, apex acuminate; fertile scales lanceolate, convex, (6–) 7–8 mm, apex narrowly acute, low midrib shortexcurrent or not. Flowers: perianth bristles 6, excurved, plumose from base to midbristle, 5–7.5 mm, antrorsely barbellate to tip. Fruits 1–2 per spikelet, 2.3–2.6 × 1.1–1.2 mm; body brown, short-stipitate, tumidly obovoid, subterete, 1.8–2 mm, margin low, broad; surfaces interruptedly transversely wavyrugulose; tubercle broadly and concavely conic, 0.5–0.7 mm high, base shallowly 2-lobed, discoid, abruptly narrowed to blunt tip.


Phenology: Fruiting spring–fall or all year.
Habitat: Sands and sandy peats of pine flatwoods scrub and flatwoods-sandscrub transition
Elevation: 0–50 m

Discussion

Of conservation concern.

Rhynchospora megaplumosa is local in central peninsular Florida. It often shares habitat with R. pineticola, and it is taxonomically nearest it in series Plumosae. Distinctive are the longer, paler, narrower spikelets, the longer fertile scales, and perianth bristles of R. megaplumosa. In fact, the perianth bristles of R. megaplumosa are the longest known in the series. While the bristles of all other Plumosae are erect, hugging the achene body, those of R. megaplumosa bend outward so strongly that they push away subtending scales; bristles are conspicuously exposed at maturity.

Selected References

None.

Lower Taxa

None.

"shortened" is not a number."wider" is not a number.

... more about "Rhynchospora megaplumosa"
acute;acuminate;triquetrous +
Robert Kral +
E. L. Bridges & Orzell +
pale-brown +  and dark-brown +
abruptly narrowed +  and blunt +
involute-sulcate +
scabridulous +  and scabrid +
tapering +  and concave +
0.2 cm2 mm <br />0.002 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
short-stipitate +
warty +, papillate +, alveolate +  and pitted +
subterete +  and obovoid +
0.18 cm1.8 mm <br />0.0018 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
glumaceous +  and foliaceous +
2-ranked +  and arranged +
ascending +  and appressed +
parallel +  and divergent +
terete +, rolled +  and plicate +
erect +  and arching-ascending +
wand-like +
0–50 m +
distalmost +
0.23 cm2.3 mm <br />0.0023 m <br /> (0.26 cm2.6 mm <br />0.0026 m <br />) +
0.11 cm1.1 mm <br />0.0011 m <br /> (0.12 cm1.2 mm <br />0.0012 m <br />) +
biconvex +  and trigonous +
Sands and sandy peats of pine flatwoods scrub and flatwoods-sandscrub transition +
close +  and cluster +
broadly turbinate +  and hemispheric +
erect +, rarely +  and spreading +
3-ranked +  and polystichous +
keeled;terete;keeled;terete +
revolute +  and involute +
decurrent +
plumed +  and barbed +
plumose +  and excurved +
0.5 cm5 mm <br />0.005 m <br /> (0.75 cm7.5 mm <br />0.0075 m <br />) +
deciduous +  and persistent +
shorter or longer +
of 2-12(-20) bristles +
Fruiting spring–fall or all year. +
2-3(-4)-carpellate +
3 (?) +  and 1 (?) +
adventitious +
0.6 cm6 mm <br />0.006 m <br /> (0.7 cm7 mm <br />0.007 m <br />) +
basal +  and proximal +
convex;lanceolate +
0.7 cm7 mm <br />0.007 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
cylindric +
1 +, 3 +  and 100 +
lanceoloid +
0.8 cm8 mm <br />0.008 m <br /> (1 cm10 mm <br />0.01 m <br />) +
2 +  and 3 +
septate +, hollow +  and solid +
compressed +, terete +  and trigonous +
papillate +
cleft +, 2-fid +  and undivided +
wavyrugulose +
Dichromena +  and Psilocarya +
Rhynchospora megaplumosa +
Rhynchospora +
species +
sulcate +  and 2-edged +
0.5mm +  and 0.7mm +
plant +  and cespitose +