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Carex Group 6
See list of 74 species in this group-
1a. Leaf sheaths, and often the blades, pubescent
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2a. Perigynia (6.5–) 7–12 mm long, with a beak 2.1–4 mm long that is terminated by 2 teeth (1.2–) 1.5–3 mm long; style persistent at summit of achene (in part)
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2b. Perigynia 2–5 mm long, without a beak or with a beak up to 1.5 mm long that is terminated by 2 teeth up to 0.5 mm long; style deciduous from achene
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3a. Perigynia beakless or essentially so; adaxial surface of leaf blades without 2 marginal veins more prominent than midvein (in part)
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3b. Perigynia with a distinct beak; adaxial surface of leaf blades usually with 2 marginal veins that are more prominent than midvein (in part)
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1b. Leaf sheaths and blades glabrous or scabrous, but not pubescent
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4a. Style persistent on achene; sheaths, and often blades, of larger leaves septate-nodulose
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5a. Body of perigynium obconic, abruptly tapering to the beak; terminal spike gynecandrous or entirely staminate (in part)
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5b. Body of perigynium lanceoloid or ellipsoid to ovoid or rhombic-ovoid, gradually to moderately tapering to the beak; terminal spike staminate
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6a. Perigynia 10–20 mm long; staminate spikes usually 1 per plant; carpellate spikes compact, globose to ovoid or obovoid (in part)
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6b. Perigynia (3.2–) 3.6–12.5 mm long; staminate spikes mostly 1–3 per plant; carpellate spikes compact to elongate, obloid or ovoid to cylindric (sometimes nearly globose in a few species)
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7a. Carpellate scales with a long, scabrous awn, the body of the scale often ciliate on the margins (in part)
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7b. Carpellate scales without prominent scabrous awns (sometimes with a smooth awn in C. striata), without ciliate margins
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8a. Perigynia with 5–14 (–15) veins, relatively thin-walled (in part)
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8b. Perigynia with 14–28 veins, firm, thick-walled (in part)
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4b. Style deciduous from achene; sheaths and blades not septate-nodulose (except in section Ceratocystis and very rarely others)
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9a. Perigynia with a serrulate wing-margin (this often revolute); achenes 4–7.5 mm long; inflorescence usually composed of 20 or more spikes densely aggregated together into ± a single cluster (the lowest spike sometimes removed from the others) (in part)
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9b. Perigynia without a wing-margin; achenes 1–2.7 mm long; inflorescence composed of 1–9 spikes, these not aggregated into a dense cluster (except in C. media)
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10a. Uppermost spike gynecandrous
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11a. Perigynia minutely papillose; adaxial surface of leaf blades without 2 marginal veins more prominent than midvein; leaf blades V-shaped in cross-section (at least when young); lateral spikes globose to obloid, 5–20 (–25) mm long
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11b. Perigynia without minute papillae; adaxial surface of leaf blades usually with 2 marginal veins that are more prominent than midvein; leaf blades M-shaped cross-section (at least when young), sometimes ± flat at maturity; lateral spikes cylindric, 15–60 mm long (in part)
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10b. Uppermost spike entirely staminate or androgynous
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12a. Perigynia minutely papillose
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13a. Lateral spikes arching to nodding; some roots with a dense, felt-like pubescence of yellow-brown hairs
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13b. Lateral spikes erect or ascending; roots without dense pubescence (in part)
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12b. Perigynia smooth
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14a. Lowest carpellate scales concealing and much surpassing the perigynia, entirely green, leaf-like (in part)
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14b. Lowest carpellate scales not surpassing perigynia, green to yellow-green or brown, with hyaline margins, not leaflike
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15a. Lower perigynia in each spike horizontally spreading to reflexed; leaf sheaths, and often blades, of larger leaves septate-nodulose (in part)
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15b. Lower perigynia in each spike ascending to spreading-ascending; leaf sheaths and blades not septate-nodulose
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16a. Lateral spikes 25–80 mm long; adaxial surface of leaf blades with 2 marginal veins more prominent than midvein; leaf blades M-shaped in cross-section (at least when young), sometimes ± flat at maturity (in part)
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16b. Lateral spikes 4.5–11.3 mm long; adaxial surface of leaf blades without 2 marginal veins more prominent than midvein; leaf blades V-shaped in cross-section (at least when young) (in part)
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Each photo represents one species in this subgroup.