Cyperus bipartitus

Torrey

Ann. Lyceum Nat. Hist. New York 3: 257. 1836.

Common names: Shining flatsedge
Illustrated
Synonyms: Cyperus rivularis Kunth
Treatment appears in FNA Volume 23. Treatment on page 161. Mentioned on page 142, 159.

Herbs, annual, densely cespitose, with fibrous-roots. Culms roundly trigonous, 3–25 (–30) cm × 0.3–1.4 mm, glabrous. Leaves 1–3, V-shaped, 1–8 cm × 1–2 mm. Inflorescences: spike 1, loosely ovoid, compressed, 7–14 × 9–14 mm; rays 1–4, to 2 (–3) cm; bracts 2–3, horizontal to ascending at 30 (–45) °, V-shaped to flat, 1–12 cm × 0.5–1.5 mm. Spikelets 3–5 (–8), flattened, oblong to oblong-lanceoloid, 8–18 × 2–2.6 (–3) mm; floral scales (6–) 10–26 (–32), closely imbricate, laterally light to dark-brown, medially light-brown, laterally ribless, medially 2–3-ribbed, 2-keeled, oblong to ovate, 1.9–2.7 × 1.8–2.3 mm, apex obtuse. Flowers: stamens 2–3; anthers 0.4–0.5 mm, connective not prolonged; styles 0.6–1 mm; stigmas 1–1.5 mm. Achenes black, network of ridges forming isodiametric or square cells, sessile, obovoid to ovoid, 1–1.3 (–1.5) × (0.6–) 0.8 mm, apex apiculate, surfaces minutely punctate.


Phenology: Fruiting summer.
Habitat: Emergent shorelines, ditches, puddles, often in disturbed places
Elevation: 0–1500 m

Distribution

V23 255-distribution-map.jpg

Ont., Que., Ala., Ariz., Ark., Calif., Colo., Conn., Del., D.C., Ga., Ill., Ind., Iowa, Kans., Ky., La., Maine, Md., Mass., Mich., Minn., Miss., Mo., Nebr., Nev., N.H., N.J., N.Mex., N.Y., N.C., N.Dak., Ohio, Okla., Oreg., Pa., R.I., S.C., S.Dak., Tenn., Tex., Utah, Vt., Va., Wash., W.Va., Wis., Mexico, Central America, South America

Discussion

Selected References

None.

Lower Taxa

None.
... more about "Cyperus bipartitus"
0.13 cm1.3 mm <br />0.0013 m <br /> (0.15 cm1.5 mm <br />0.0015 m <br />) +
0.06 cm0.6 mm <br />6.0e-4 m <br /> (0.08 cm0.8 mm <br />8.0e-4 m <br />) +
0.1 cm1 mm <br />0.001 m <br /> (0.13 cm1.3 mm <br />0.0013 m <br />) +
obovoid;ovoid +
0.04 cm0.4 mm <br />4.0e-4 m <br /> (0.05 cm0.5 mm <br />5.0e-4 m <br />) +
Gordon C. Tucker* +, Brian G. Marcks* +  and J. Richard Carter * +
Torrey +
shortened +
persistent +  and deciduous +
decurrent +
Undefined subg. Pycreus +
w--shaped +  and keeled +
glumaceous +  and foliaceous +
2-ranked +  and arranged +
1 cm10 mm <br />0.01 m <br /> (12 cm120 mm <br />0.12 m <br />) +
horizontal +  and ascending +
v-shaped +  and flat +
0.05 cm0.5 mm <br />5.0e-4 m <br /> (0.15 cm1.5 mm <br />0.0015 m <br />) +
parallel +  and divergent +
terete +, rolled +  and plicate +
square +  and isodiametric +
Shining flatsedge +
not prolonged +
25 cm250 mm <br />0.25 m <br /> (30 cm300 mm <br />0.3 m <br />) +
3 cm30 mm <br />0.03 m <br /> (25 cm250 mm <br />0.25 m <br />) +
scabridulous +
trigonous +
0.3mm;1.4mm +
Ont. +, Que. +, Ala. +, Ariz. +, Ark. +, Calif. +, Colo. +, Conn. +, Del. +, D.C. +, Ga. +, Ill. +, Ind. +, Iowa +, Kans. +, Ky. +, La. +, Maine +, Md. +, Mass. +, Mich. +, Minn. +, Miss. +, Mo. +, Nebr. +, Nev. +, N.H. +, N.J. +, N.Mex. +, N.Y. +, N.C. +, N.Dak. +, Ohio +, Okla. +, Oreg. +, Pa. +, R.I. +, S.C. +, S.Dak. +, Tenn. +, Tex. +, Utah +, Vt. +, Va. +, Wash. +, W.Va. +, Wis. +, Mexico +, Central America +  and South America +
0–1500 m +
light-brown +, laterally light +  and dark-brown +
0.19 cm1.9 mm <br />0.0019 m <br /> (0.27 cm2.7 mm <br />0.0027 m <br />) +
oblong +  and ovate +
0.18 cm1.8 mm <br />0.0018 m <br /> (0.23 cm2.3 mm <br />0.0023 m <br />) +
hypogynous +  and subtending +
biconvex +  and trigonous +
Emergent shorelines, ditches, puddles, often in disturbed places +
subumbellate +  and capitate +
spreading +  and erect +
multi-ranked +, 2-ranked +, 3-ranked +  and alternate +
1cm +  and 8cm +
v--shaped +
0.1 cm1 mm <br />0.001 m <br /> (0.2 cm2 mm <br />0.002 m <br />) +
with (1-)3-6(-30) bristles and/or scales +
Fruiting summer. +
2-3(-4)-carpellate +
antrorse +  and extrorse +
3 (?) +  and 1 (?) +
Ann. Lyceum Nat. Hist. New York +
nearly +  and wingless +
2 cm20 mm <br />0.02 m <br /> (3 cm30 mm <br />0.03 m <br />) +
unequal +
1 +  and 4 +
0 cm0 mm <br />0 m <br /> (2 cm20 mm <br />0.02 m <br />) +
adventitious +
basal +  and proximal +
cylindric;compressed +
cylindric +
Illustrated +
0.7 cm7 mm <br />0.007 m <br /> (1.4 cm14 mm <br />0.014 m <br />) +
compressed;ovoid +
0.9 cm9 mm <br />0.009 m <br /> (1.4 cm14 mm <br />0.014 m <br />) +
loosely spicate +  and more or less digitate +
0.26 cm2.6 mm <br />0.0026 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
0.8 cm8 mm <br />0.008 m <br /> (1.8 cm18 mm <br />0.018 m <br />) +
oblong;oblong-lanceoloid +
2mm;2.6mm +
2 (?) +  and 3 (?) +
septate +, hollow +  and solid +
compressed +, terete +  and trigonous +
papillate +
0.1 cm1 mm <br />0.001 m <br /> (0.15 cm1.5 mm <br />0.0015 m <br />) +
2-3-fid +
0.06 cm0.6 mm <br />6.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
Cyperus rivularis +
Cyperus bipartitus +
Cyperus subg. Pycreus +
species +
tuberous +, stoloniferous +  and rhizomatous +
herb +  and cespitose +