Cyperus diandrus

Torrey

Cat. Pl. New York, 90. 1819.

IllustratedEndemic
Synonyms: Pycreus diander (Torrey) C. B. Clarke
Treatment appears in FNA Volume 23. Treatment on page 161. Mentioned on page 142, 157, 159.

Herbs, annual, cespitose, with fibrous-roots. Culms trigonous, 4–25 (–35) cm, glabrous. Leaves flat, 5–20 cm × 1.5–3 mm. Inflorescences: heads ± digitate, 12–22 mm diam.; rays 3–6, 1–6 cm; bracts 1–4, ± horizontal, flat, 1.5–15 cm × 1.5–3 mm. Spikelets 6–12, oblong-lanceoloid, compressed, 5–10 × 2.8–3.2 mm; floral scales 8–28, closely imbricate, stramineous to light-brown or clear (marginal band bright red, spikelet thus appearing dark-margined), laterally ribless, oblong to ovate, 2.5–3 × 1.6–1.9 mm. Flowers: stamens 2 (–3); anthers 0.3 mm, connective apex reddish, subulate, 0.1–0.2 mm; styles 0.3–0.5 mm; stigmas 2.2–3.1 mm. Achenes brown, network of ridges forming isodiametric or square cells, sessile or stipitate, obovoid to ovoid, 1–1.2 × 0.5–0.6 mm, stipe, if present, 0.1 mm, apex obtuse, apiculate, surfaces minutely punctate.


Phenology: Fruiting summer.
Habitat: Emergent shorelines, in sandy, peaty, or slightly brackish areas (though seldom where disturbed)
Elevation: 0–600 m

Distribution

V23 256-distribution-map.jpg

N.B., N.S., Ont., Que., Conn., Del., Ill., Ind., Iowa, Maine, Md., Mass., Mich., Minn., Mo., Nebr., N.H., N.J., N.Y., Pa., R.I., Vt., Va.

Discussion

Selected References

None.

Lower Taxa

None.

"shortened" is not a number.

... more about "Cyperus diandrus"
stipitate +  and sessile +
0.1 cm1 mm <br />0.001 m <br /> (0.12 cm1.2 mm <br />0.0012 m <br />) +
obovoid;ovoid +
0.5mm;0.6mm +
0.3 cm3 mm <br />0.003 m <br /> (?) +
Gordon C. Tucker* +, Brian G. Marcks* +  and J. Richard Carter * +
Torrey +
persistent +  and deciduous +
decurrent +
Undefined subg. Pycreus +
w--shaped +  and keeled +
glumaceous +  and foliaceous +
2-ranked +  and arranged +
1.5 cm15 mm <br />0.015 m <br /> (15 cm150 mm <br />0.15 m <br />) +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
parallel +  and divergent +
terete +, rolled +  and plicate +
square +  and isodiametric +
scabridulous +
trigonous +
4 cm40 mm <br />0.04 m <br /> (25 cm250 mm <br />0.25 m <br />) +
N.B. +, N.S. +, Ont. +, Que. +, Conn. +, Del. +, Ill. +, Ind. +, Iowa +, Maine +, Md. +, Mass. +, Mich. +, Minn. +, Mo. +, Nebr. +, N.H. +, N.J. +, N.Y. +, Pa. +, R.I. +, Vt. +  and Va. +
0–600 m +
stramineous +  and light-brown or clear +
0.25 cm2.5 mm <br />0.0025 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
oblong +  and ovate +
0.16 cm1.6 mm <br />0.0016 m <br /> (0.19 cm1.9 mm <br />0.0019 m <br />) +
hypogynous +  and subtending +
biconvex +  and trigonous +
Emergent shorelines, in sandy, peaty, or slightly brackish areas (though seldom where disturbed) +
1.2 cm12 mm <br />0.012 m <br /> (2.2 cm22 mm <br />0.022 m <br />) +
subumbellate +  and capitate +
spreading +  and erect +
multi-ranked +, 2-ranked +, 3-ranked +  and alternate +
5 cm50 mm <br />0.05 m <br /> (?) +  and 20 cm200 mm <br />0.2 m <br /> (?) +
0.15 cm1.5 mm <br />0.0015 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
with (1-)3-6(-30) bristles and/or scales +
Fruiting summer. +
2-3(-4)-carpellate +
antrorse +  and extrorse +
3 (?) +  and 1 (?) +
Cat. Pl. New York, +
nearly +  and wingless +
unequal +
3 +  and 6 +
1 cm10 mm <br />0.01 m <br /> (6 cm60 mm <br />0.06 m <br />) +
adventitious +
basal +  and proximal +
cylindric;compressed +
cylindric +
Illustrated +  and Endemic +
loosely spicate +  and more or less digitate +
0.5 cm5 mm <br />0.005 m <br /> (1 cm10 mm <br />0.01 m <br />) +
6 +  and 12 +
compressed;oblong-lanceoloid +
2.8mm;3.2mm +
septate +, hollow +  and solid +
compressed +, terete +  and trigonous +
papillate +
0.22 cm2.2 mm <br />0.0022 m <br /> (0.31 cm3.1 mm <br />0.0031 m <br />) +
0.1 cm1 mm <br />0.001 m <br /> (?) +
2-3-fid +
0.03 cm0.3 mm <br />3.0e-4 m <br /> (0.05 cm0.5 mm <br />5.0e-4 m <br />) +
Pycreus diander +
Cyperus diandrus +
Cyperus subg. Pycreus +
species +
tuberous +, stoloniferous +  and rhizomatous +
herb +  and cespitose +