Fimbristylis annua

(Allioni) Roemer & Schultes in J. J. Roemer et al.

in J. J. Roemer et al., Syst. Veg. 2: 95. 1817.

Illustrated
Basionym: Scirpus annuus Allioni Fl. Pedem. 2: 277, plate 88, fig. 5. 1785 Fimbristylis diphylla var. tomentosa Barros 1945 Scirpus sulcatus Elliott 1816
Synonyms: Fimbristylis alamosana Fernald Fimbristylis arenicola Wiggins Fimbristylis baldwiniana (Schultes) Torrey Fimbristylis darlingtoniana Pennell Fimbristylis hirtella Vahl Fimbristylis holwayana Fernald Fimbristylis serratula Vahl Fimbristylis verrucosa C. Presl Scirpus baldwinianus Schultes Scirpus depauperatus Muhlenberg Scirpus elliottii Sprengel
Treatment appears in FNA Volume 23. Treatment on page 126. Mentioned on page 123, 125.

Plants annual, cespitose, 5–50 cm, base soft; rhizomes absent. Leaves nearly distichous, 1/2 to equal length of culms; sheaths bristlyciliate apically, backs glabrous or hirtellous; ligule present, complete; blades narrowly linear, 1–1.5 (–2) mm wide, flat to shallowly involute, margins ciliate-scabrid, adaxial and abaxial surfaces glabrous or pubescent. Inflorescences: anthelae simple or compound, mostly open, diffuse, ascending-branched, longer than broad; scapes slender, 1 mm thick, angular; proximalmost involucral-bract longer or shorter than anthela. Spikelets tan to brown or redbrown, ovoid to lanceovoid, 3–8 mm; fertile scales broadly oblong to ovate, 2 mm, acute to obtuse-angled, smooth, midrib reaching apex or excurrent as mucro. Flowers: stamens 1 (–2); styles 2-fid, flat, fimbriate. Achenes white to brown, often iridescent, lenticular or obovoid to pyriformobovoid, 1 mm, cancellate, with 5–12 longitudinal ribs per side, alternating with as many rows of horizontally rectangular pits; warts of achene more usually distributed, or achene (rarely) smooth. 2n = 30.


Phenology: Fruiting summer–fall, all year southward.
Habitat: Various moist to wet substrates, often on exposed, recently disturbed soils around or in shallow temporary pools in outcrops, in savannas, fields, and paddies
Elevation: 0–1000 m

Distribution

V23 194-distribution-map.jpg

Ala., Ariz., Ark., Del., D.C., Fla., Ga., Ill., Ind., Kans., Ky., La., Md., Mich., Miss., Mo., N.J., N.Y., N.C., Ohio, Okla., Pa., S.C., Tenn., Tex., Va., Mexico, West Indies, Bermuda, Central America, South America, Eurasia, Africa, Atlantic Islands, Indian Ocean Islands, Pacific Islands, Australia

Discussion

The extensive, yet incomplete, synonymy above partly illustrates the polymorphic nature of Fimbristylis annua, there being many “stabilized” morphs in specialized habitats and much exchange of achenes mixed with grass seeds (particularly rice).

Selected References

None.

Lower Taxa

None.

"equal" is not a number.

... more about "Fimbristylis annua"
white +  and brown +
reticulate-honeycombed +
obovoid;lenticular +
pubescent +  and glabrous +
ascending-branched +, open +, compound +  and simple +
longer than broad +
Robert Kral +
(Allioni) Roemer & Schultes in J. J. Roemer et al. +
shortened +
hirtellous;glabrous +
deciduous +
enlarged +
Scirpus annuus +, Fimbristylis diphylla var. tomentosa +  and Scirpus sulcatus +
flat +  and shallowly involute +
1mm;1.5mm +
glumaceous +  and foliaceous +
2-ranked +  and arranged +
ascending +  and appressed +
parallel +  and divergent +
terete +, rolled +  and plicate +
3-5-angled +, compressed +  and terete +
Ala. +, Ariz. +, Ark. +, Del. +, D.C. +, Fla. +, Ga. +, Ill. +, Ind. +, Kans. +, Ky. +, La. +, Md. +, Mich. +, Miss. +, Mo. +, N.J. +, N.Y. +, N.C. +, Ohio +, Okla. +, Pa. +, S.C. +, Tenn. +, Tex. +, Va. +, Mexico +, West Indies +, Bermuda +, Central America +, South America +, Eurasia +, Africa +, Atlantic Islands +, Indian Ocean Islands +, Pacific Islands +  and Australia +
0–1000 m +
hypogynous +  and subtending +
biconvex +  and trigonous +
Various moist to wet substrates, often on exposed, recently disturbed soils around or in shallow temporary pools in outcrops, in savannas, fields, and paddies +
interrupted +  and continuous +
compound +  and simple +
erect +  and spreading +
with (1-)3-6(-30) bristles and/or scales +
Fruiting summer–fall, all year southward. +
2-3(-4)-carpellate +
rectangular +
3 (?) +  and 1 (?) +
in J. J. Roemer et al., Syst. Veg. +
adventitious +
basal +  and proximal +
acute;obtuse-angled +
2 cm20 mm <br />0.02 m <br /> (?) +
slender +
1 cm10 mm <br />0.01 m <br /> (?) +
cylindric +
W1 +  and Illustrated +
tan +  and brown or redbrown +
single +, 1 +  and 80 +
ovoid;lanceovoid +
0.3 cm3 mm <br />0.003 m <br /> (0.8 cm8 mm <br />0.008 m <br />) +
septate +, hollow +  and solid +
compressed +, terete +  and trigonous +
papillate +
fimbriate +  and 2-fid +
Fimbristylis alamosana +, Fimbristylis arenicola +, Fimbristylis baldwiniana +, Fimbristylis darlingtoniana +, Fimbristylis hirtella +, Fimbristylis holwayana +, Fimbristylis serratula +, Fimbristylis verrucosa +, Scirpus baldwinianus +, Scirpus depauperatus +  and Scirpus elliottii +
Fimbristylis annua +
Fimbristylis +
species +
not +  and rhizomatous +
plant +  and cespitose +