Carex membranacea

Hooker in G. F. Lyon

in G. F. Lyon, Attempt Repulse Bay, 195. 1825.

Common names: Carex membraneux
Illustrated
Synonyms: Carex physochlaena T. Holm
Treatment appears in FNA Volume 23. Treatment on page 504. Mentioned on page 500, 502.

Plants cespitose; rhizomes long, lax. Culms trigonous in cross-section, 13–55 cm, scabrous distally. Leaves: basal sheaths reddish-brown; ligules shorter than wide; blades mid to dark green, V-shaped, 2.5–5 (–6.2) mm wide, glabrous. Inflorescences 2.5–10 (–13) cm; proximal bract 0.6–19 cm, shorter than or equaling inflorescence; proximal 1–3 spikes pistillate, erect; terminal 1–3 spikes staminate. Pistillate scales ovate, 2.2–4.5 × 1–1.7 mm, as long as or shorter than perigynia, margins entire, apex obtuse or acute, awnless. Perigynia spreading or reflexed, often dark-colored, obscurely few-veined, veins not running into beak, elliptic, 2.2–4.1 × 1.3–2.2 mm, abruptly contracted; beak 0.2–0.8 mm, obscurely bidentulate, smooth, teeth straight, to 0.3 mm. Achenes yellow, trigonous, smooth. Stigmas 3.2n = 74, 76–80.


Phenology: Fruiting summer.
Habitat: Open wetlands, wet tundra, muskeg
Elevation: 0–2000 m

Distribution

V23 935-distribution-map.jpg

B.C., Nfld. and Labr., N.W.T., Nunavut, Que., Yukon, Alaska, ne Asia

Discussion

Carex membranacea is common throughout arctic and high boreal regions of North America. It is noticeably absent from Greenland and occurs in Eurasia only in the Russian Far East (Chukotka and the Koryak mountains).

Morphologically Carex membranacea is closest to C. rotundata. Leaf and stem shape easily distinguish those two species but shape is often difficult to evaluate on herbarium specimens. Leaf sheath coloration, although not a definitive character, is helpful in distinguishing between the two species. Carex membranacea almost always has red basal sheaths; sheaths are usually brown in C. rotundata.

Selected References

None.

Lower Taxa

None.
... more about "Carex membranacea"
trigonous +
not papillose +
A. A. Reznicek +  and Bruce A. Ford +
Hooker in G. F. Lyon +
shortened +
not +  and fibrous +
truncate +  and rounded +
Vesicariae +
bidentulate +
emarginate +  and bidentate +
0.02 cm0.2 mm <br />2.0e-4 m <br /> (0.08 cm0.8 mm <br />8.0e-4 m <br />) +
v--shaped +
2.5mm;5mm +
glumaceous +  and foliaceous +
2-ranked +  and arranged +
ascending +  and appressed +
scale-like +  and leaflike +
parallel +  and divergent +
terete +, rolled +  and plicate +
Carex membraneux +
brown +, reddish-brown +  and reddish purple +
trigonous +
13 cm130 mm <br />0.13 m <br /> (55 cm550 mm <br />0.55 m <br />) +
B.C. +, Nfld. and Labr. +, N.W.T. +, Nunavut +, Que. +, Yukon +, Alaska +  and ne Asia +
0–2000 m +
open +, pistillate +  and staminate +
hypogynous +  and subtending +
biconvex +  and trigonous +
Open wetlands, wet tundra, muskeg +
10 cm100 mm <br />0.1 m <br /> (13 cm130 mm <br />0.13 m <br />) +
2.5 cm25 mm <br />0.025 m <br /> (10 cm100 mm <br />0.1 m <br />) +
prophyllate +, pedunculate +  and pistillate +
multi-ranked +, 2-ranked +, 3-ranked +  and alternate +
basal +  and cauline +
with (1-)3-6(-30) bristles and/or scales +
reflexed +  and spreading +
0.2 cm2 mm <br />0.002 m <br /> (1.2 cm12 mm <br />0.012 m <br />) +
Fruiting summer. +
2-3(-4)-carpellate +
3 (?) +  and 1 (?) +
short-sheathed +, sheathless +  and leaflike +
0.6 cm6 mm <br />0.006 m <br /> (19 cm190 mm <br />0.19 m <br />) +
in G. F. Lyon, Attempt Repulse Bay, +
adventitious +
green +  and dark-brown +
0.22 cm2.2 mm <br />0.0022 m <br /> (0.45 cm4.5 mm <br />0.0045 m <br />) +
basal +  and proximal +
1mm;1.7mm +
septate-nodulose +
Illustrated +
staminate +  and pistillate +
1 (?) +  and 3 (?) +
septate +, hollow +  and solid +
compressed +, terete +  and trigonous +
papillate +
persistent +
2-3(-4)-fid +
Carex physochlaena +
Carex membranacea +
Carex sect. Vesicariae +
species +
straight +
0 cm0 mm <br />0 m <br /> (0.03 cm0.3 mm <br />3.0e-4 m <br />) +
0.22 cm2.2 mm <br />0.0022 m <br /> (0.41 cm4.1 mm <br />0.0041 m <br />) +
1.3mm +  and 2.2mm +
plant +  and cespitose +