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Carex Group 7
See list of 64 species in this group-
1a. Style persistent on achene; perigynia (2.2–) 3.4–19 mm long
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2a. Teeth of perigynium reflexed; achenes narrow-obloid
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2b. Teeth of perigynium erect; achenes obloid-ovoid or obloid-obovoid to ellipsoid, rhomboid, or rhombic-ovoid
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3a. Body of perigynium obconic, abruptly tapering to the beak; uppermost spike gynecandrous or entirely staminate (in part)
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3b. Body of perigynium lanceoloid to ovoid or obovoid, moderately to gradually tapering to the beak; uppermost spike staminate
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4a. Carpellate scales with a long, scabrous awn, the body of the scale often ciliate on the margins (in part)
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4b. Carpellate scales either without prominent scabrous awns or with awns much shorter than the body of the scale, without ciliate margins
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5a. Perigynia 8.7–12.1 mm long, lanceoloid, 4–7 times as long as wide; basal sheaths yellow-brown to brown, without anthocyanins
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5b. Perigynia 11–19 mm long, narrow-ovoid, less than 7 times as long as wide; basal sheaths usually tinged with anthocyanic pigments (in part)
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1b. Style deciduous from achene; perigynia 1.5–6.8 (–9.5) mm long
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6a. Leaf blades V-shaped or U-shaped in cross-section (at least when young); adaxial surface of leaf blades without 2 marginal veins that are more prominent than midvein
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7a. Bracts of inflorescence consisting of only a sheath; perigynia green, maturing glossy, dark brown
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7b. At least the lowest bracts of the inflorescence with a short blade; perigynia variously colored, but not glossy dark brown at maturity
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8a. Lower perigynia in each spike horizontally spreading to reflexed; carpellate spikes globose to short-ellipsoid or short-cylindric (in part)
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8b. Lower perigynia in each spike ascending to spreading-ascending; carpellate spikes short-cylindric or ovoid to narrow-cylindric
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9a. Abaxial leaf blade and surface of perigynia minutely papillose; plants colonial from long rhizomes, with strongly glaucous leaves (in part)
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9b. Abaxial leaf blade and surface of perigynia without papillae; plants loosely to densely cespitose from short rhizomes (colonial from long rhizomes in C. crawei), with green to moderately glaucous leaves
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10a. Perigynia rounded at base, apically with convexly rounded sides, often with red-brown or yellow streaks and spots (in part)
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10b. Perigynia tapering to base, apically with flat or somewhat convex sides, without streaks or spots
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11a. Perigynia with 2 evident marginal veins, the remaining veins obscure, the beak erect; achenes 1.2–1.7 mm long; lateral spikes, especially the lower, usually spreading or drooping (ascending in alpine populations)
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11b. Perigynia with (22–) 25–32 evident veins, the beak usually curved or bent; achenes 2–2.8 mm long; lateral spikes usually erect or ascending (in part)
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6b. Leaf blades M-shaped in cross-section (at least when young), sometimes ± flat at maturity; adaxial surface of leaf blades usually with 2 marginal veins that are more prominent than midvein
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12a. Perigynium with 2 evident marginal veins, the remaining veins obscure or evident only in the basal portion of the perigynium body
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13a. Perigynium abruptly tapered to a beak 1.7–4 mm long, the beak nearly as long as the perigynium body and terminated by 2 hyaline teeth 0.5–1.4 mm long (in part)
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13b. Perigynium beakless or moderately tapering to a beak 0.1–1.8 (–2.2) mm long, the beak definitely shorter than the perigynium body and entire or weakly bidentate with terminal teeth up to 0.1 mm long
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14a. Perigynium with a curved or abruptly bent beak; plants cespitose, with short rhizomes (in part)
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14b. Perigynium beakless or with a straight beak; plants colonial from long rhizomes
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15a. Perigynium neither streaked nor spotted with red-brown; abaxial leaf blade and surface of perigynia densely and minutely papillose (both usually smooth in C. vaginata) (in part)
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15b. Perigynium often streaked or dotted with red-brown; abaxial leaf blade and surface of perigynia without minute papillae (in part)
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12b. Perigynium with 2 evident marginal veins as well as 8–40+ additional distinct, fine veins that travel ± the length of the perigynium body
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16a. Perigynia rounded at base, apically with convexly rounded sides
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17a. Perigynia with impressed veins (especially in drying), without red-brown or yellow streaks or dots; carpellate scales with an awn 0.2–6 mm long (sometimes awnless in C. glaucodea)
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17b. Perigynia with elevated nerves, often with red-brown or yellow streaks or dots; carpellate scales sharply pointed to shortly awned, the awns up to 0.5 mm long when present (in part)
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16b. Perigynia tapering to base, apically with flat or somewhat convex sides
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18a. Plants colonial from long rhizomes; abaxial leaf blade and surface of perigynia minutely papillose (view at 20 × or higher magnification; both usually smooth inC. vaginata) (in part)
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18b. Plants loosely to densely cespitose from short rhizomes; abaxial leaf blade and surface of perigynia without minute papillae
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19a. Perigynia with 8–20 veins; beak of perigynium (when present) terminated by 2 teeth 0.2–1 mm long; uppermost spike gynecandrous or entirely staminate (in part)
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19b. Perigynia with (22–) 25–40+ veins; beak of perigynium ± entire, without 2 apical teeth; uppermost spike entirely staminate
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20a. Perigynia with sharp angles and flat faces, usually with 40 or more closely spaced veins; plants often with a long-peduncled, carpellate spike borne from near the base of the plant
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20b. Perigynia with rounded angles and convex faces, mostly with 22–32 veins; plants usually without basal spikes (in part)
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Each photo represents one species in this subgroup.