Cyperus hystricinus

Fernald

Rhodora 8: 127. 1906.

Common names: Bristly flatsedge
IllustratedEndemic
Synonyms: Cyperus retrofractus var. hystricinus (Fernald) Kükenthal
Treatment appears in FNA Volume 23. Mentioned on page 181.

Herbs, perennial, cespitose, with well-developed rhizomes. Culms trigonous, 30–100 cm × 2–4 mm, basally cormlike, glabrous. Leaves flat to broadly V-shaped, 20–70 cm × 4–6 mm, glabrous except for marginal prickles. Inflorescences: spikes loosely to densely ovoid, oblong (2 times long as wide), 10–12 × 6–9 mm; rays 6–11, 1–16 cm, glabrous; bracts 5–10, ascending at 30–45°, flat, 6–25 cm × 3–6 mm; rachilla persistent, wings 0.5 mm wide, covering nearly entire length of achene. Spikelets (20–) 40–100 (–120), proximal spikelets reflexed somewhat, distal ones divaricate, ± terete, lanceoloid, 6–6.8 × 1–1.4 mm; floral scales persistent, 1–2 (–3), appressed, golden brown, lanceolate, laterally 5–6-ribbed, 3.8–4.9 × 1.4–1.6 mm, apex mucronate, mucro at most 0.3 mm. Flowers: anthers 1–1.3 mm; styles 0.8–1 mm; stigmas 2–3 mm. Achenes brown, sessile, linear, 2.5–2.8 × 0.5–0.7 mm, apex obtuse, apiculate, surfaces muriculate.


Phenology: Fruiting late summer–early fall (Jul–Sep).
Habitat: Xeric, sandy soils of sand hills and pine barrens
Elevation: 0–200 m

Distribution

V23 309-distribution-map.jpg

Ala., Ark., Del., D.C., Ga., La., Md., Miss., Mo., N.J., N.C., Tex., Va.

Discussion

Cyperus hystricinus resembles C. plukenetii and C. retrofractus; it can be readily distinguished from both by its glabrous culms. Overly mature specimens of C. lancastriensis are frequently misidentified as C. hystricinus; C. hystricinus may be confirmed by its narrow, nearly glabrous leaves and bracts, golden brown spikelets, longer, narrower achenes, and elongated rhizome internodes (to 15 mm vs. 5 mm in 76. C. lancastriensis).

Selected References

None.

Lower Taxa

None.

... more about "Cyperus hystricinus"
0.25 cm2.5 mm <br />0.0025 m <br /> (0.28 cm2.8 mm <br />0.0028 m <br />) +
flattened;trigonous +
0.5mm;0.7mm +
0.1 cm1 mm <br />0.001 m <br /> (0.13 cm1.3 mm <br />0.0013 m <br />) +
Gordon C. Tucker* +, Brian G. Marcks* +  and J. Richard Carter * +
Fernald +
shortened +
persistent +  and deciduous +
decurrent +
w--shaped +  and keeled +
glumaceous +  and foliaceous +
2-ranked +  and arranged +
6 cm60 mm <br />0.06 m <br /> (25 cm250 mm <br />0.25 m <br />) +
0.3 cm3 mm <br />0.003 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
parallel +  and divergent +
terete +, rolled +  and plicate +
Bristly flatsedge +
30 cm300 mm <br />0.3 m <br /> (100 cm1,000 mm <br />1 m <br />) +
scabridulous +
trigonous +
2mm;4mm +
0.6 cm6 mm <br />0.006 m <br /> (0.68 cm6.8 mm <br />0.0068 m <br />) +
0.1 cm1 mm <br />0.001 m <br /> (0.14 cm1.4 mm <br />0.0014 m <br />) +
Ala. +, Ark. +, Del. +, D.C. +, Ga. +, La. +, Md. +, Miss. +, Mo. +, N.J. +, N.C. +, Tex. +  and Va. +
0–200 m +
0.38 cm3.8 mm <br />0.0038 m <br /> (0.49 cm4.9 mm <br />0.0049 m <br />) +
0.14 cm1.4 mm <br />0.0014 m <br /> (0.16 cm1.6 mm <br />0.0016 m <br />) +
hypogynous +  and subtending +
biconvex +  and trigonous +
Xeric, sandy soils of sand hills and pine barrens +
subumbellate +  and capitate +
spreading +  and erect +
multi-ranked +, 2-ranked +, 3-ranked +  and alternate +
20cm +  and 70cm +
flat +  and broadly v-shaped +
0.4 cm4 mm <br />0.004 m <br /> (0.6 cm6 mm <br />0.006 m <br />) +
0 cm0 mm <br />0 m <br /> (0.03 cm0.3 mm <br />3.0e-4 m <br />) +
with (1-)3-6(-30) bristles and/or scales +
Fruiting late summer–early fall (Jul–Sep). +
2-3(-4)-carpellate +
antrorse +  and extrorse +
3 (?) +  and 1 (?) +
continuous +, articulate +, winged +  and wingless +
conspicuous +
unequal +
6 +  and 11 +
1 cm10 mm <br />0.01 m <br /> (16 cm160 mm <br />0.16 m <br />) +
well-developed +
adventitious +
basal +  and proximal +
cylindric;compressed +
cylindric +
Illustrated +  and Endemic +
1 cm10 mm <br />0.01 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
oblong;ovoid +
0.6 cm6 mm <br />0.006 m <br /> (0.9 cm9 mm <br />0.009 m <br />) +
40 +  and 100 +
septate +, hollow +  and solid +
compressed +, terete +  and trigonous +
papillate +
0.2 cm2 mm <br />0.002 m <br /> (0.3 cm3 mm <br />0.003 m <br />) +
2-3-fid +
0.08 cm0.8 mm <br />8.0e-4 m <br /> (0.1 cm1 mm <br />0.001 m <br />) +
muriculate +
Cyperus retrofractus var. hystricinus +
Cyperus hystricinus +
Cyperus subg. Cyperus +
species +
tuberous +, stoloniferous +  and rhizomatous +
herb +  and cespitose +