Fimbristylis perpusilla

R. M. Harper ex Small & Britton in J. K. Small

in J. K. Small, Fl. S.E. U.S., 188, 1327. 1903.

IllustratedEndemicConservation concern
Treatment appears in FNA Volume 23. Treatment on page 128. Mentioned on page 122, 127.

Plants annual, delicate, cespitose, slender, 2–15 cm; rhizomes absent. Leaves polystichous, spreading to ascending, mostly excurved, exceeding or exceeded by culms; sheaths entire, backs glabrous; ligule absent; blades setaceous-filiform, to 0.5 mm wide, flat to involute, sparsely scabridciliate. Inflorescences: anthelae mostly simple, open, nearly as broad as long, ascending-branching, umbelliform, of 3–10 cormose spikelets; scapes filiform, 0.5–0.6 mm thick; proximalmost involucral-bracts setaceous-bladed, exceeding anthela. Spikelets pale green to light-brown, ovoid to globose or short-cylindric, 2–5 mm; fertile scales lance-linear to oblong-linear, 1.5 mm, glabrous, midrib strongly excurrent, erect to excurved cusp. Flowers: stamens 1; styles 2-fid, slender, glabrous. Achenes pale-brown with iridescent tints, curved-cylindric, 0.4–0.6 mm, finely reticulate, in 12 vertical rows of narrowly rectangular, horizontal cells. 2n = 10.


Phenology: Fruiting summer–fall.
Habitat: Fluctuating sandy-silty shores of shallow ponds, pine savanna pools, reservoirs, ditches, and canals
Elevation: 0–100(–200) m

Distribution

V23 197-distribution-map.jpg

Del., Ga., Md., N.C., S.C., Tenn., Va.

Discussion

Of conservation concern.

The nearest relative of this ephemeral is Fimbristylis dipsacea, a similarly diminutive Eurasian and South American annual with broader, more spreadingcusped spikelets and oddly compound-papillate fruit.

Selected References

None.

Lower Taxa

None.

"shortened" is not a number.

... more about "Fimbristylis perpusilla"
reticulate-honeycombed +
curved-cylindric +
umbelliform +, ascending-branching +, open +  and simple +
Robert Kral +
R. M. Harper ex Small & Britton in J. K. Small +
deciduous +
enlarged +
flat +  and involute +
0 cm0 mm <br />0 m <br /> (0.05 cm0.5 mm <br />5.0e-4 m <br />) +
glumaceous +  and foliaceous +
2-ranked +  and arranged +
ascending +  and appressed +
parallel +  and divergent +
terete +, rolled +  and plicate +
rectangular +
3-5-angled +, compressed +  and terete +
excurved +
Del. +, Ga. +, Md. +, N.C. +, S.C. +, Tenn. +  and Va. +
0–100(–200) m +
hypogynous +  and subtending +
biconvex +  and trigonous +
Fluctuating sandy-silty shores of shallow ponds, pine savanna pools, reservoirs, ditches, and canals +
interrupted +  and continuous +
compound +  and simple +
erect +  and spreading +
polystichous +
spreading;ascending +
exceeded by culms +  and exceeding +
excurved +
with (1-)3-6(-30) bristles and/or scales +
Fruiting summer–fall. +
2-3(-4)-carpellate +
3 (?) +  and 1 (?) +
in J. K. Small, Fl. S.E. U.S., +
adventitious +
basal +  and proximal +
2-keeled +
1.5 cm15 mm <br />0.015 m <br /> (?) +
filiform +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (?) +  and 0.06 cm0.6 mm <br />6.0e-4 m <br /> (?) +
cylindric +
Illustrated +, Endemic +  and Conservation concern +
pale green +  and light-brown +
3 +  and 10 +
ovoid;globose or short-cylindric +
0.2 cm2 mm <br />0.002 m <br /> (0.5 cm5 mm <br />0.005 m <br />) +
septate +, hollow +  and solid +
compressed +, terete +  and trigonous +
papillate +
slender +
Fimbristylis perpusilla +
Fimbristylis +
species +
not +  and rhizomatous +
plant +  and cespitose +