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Carex Group 3
See list of 67 species in this group-
1a. At least the uppermost spike gynecandrous (i.e., the staminate flowers borne at the base of the spike), the others carpellate or gynecandrous
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2a. Perigynia with flat, wing-like margins (at least in the apical half), not distended to the edges by achene, without spongy tissue at the base; style persisting on summit of achene as a short apiculus
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2b. Perigynia with rounded or sharp, unwinged margins, distended to or close to the edges by achene, with spongy tissue at the base; style deciduous from summit of achene
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3a. Perigynium rounded or with a rounded edge at the margins; achene nearly filling body of perigynium
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3b. Perigynium sharp-edged at margins; achene obviously smaller than body of perigynium
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4a. At least the lower perigynia of each spike spreading; beak of perigynium 0.4–1.7 mm long; style base not enlarged (in part)
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4b. Perigynia erect to ascending; beak of perigynium 1.2–2.2 (–2.8) mm long; style base enlarged (in part)
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1b. Spikes androgynous (i.e., the staminate flowers borne at the summit of the spike)
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5a. Perigynium unequally biconvex (i.e., plump), with a smooth beak up to 0.25 mm long
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5b. Perigynium flat or planoconvex, the beak minutely serrulate in most species and 0.3–3.5 mm long
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6a. Stems produced singly or few together from elongate rhizomes, stolons, or prostrate stems
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7a. Stems leaning or prostrate, producing upright stems from the axils of dried leaves of the previous year; beak of perigynium 0.3–0.6 mm long; plants of organic soil wetlands
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7b. Stems upright, produced from elongate rhizomes; beak of perigynium 0.7–2.7 mm long; plants of sandy, gravelly, or rocky, frequently well-drained, habitats
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8a. Perigynia sharp-margined but not wing-margined, nerveless or inconspicuously nerved on the adaxial surface; plants phyllopodic, with basal tufts of leaves (in part) (in part)
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8b. Perigynia wing-margined, conspicuously nerved on the adaxial surface; plants aphyllopodic, without basal tufts of leaves
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6b. Stems cespitose, the rhizomes inconspicuous or very short
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9a. Leaf sheaths opposite the blade transversely rugose, appearing corrugated
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10a. Spikes 3–10 (–15) per inflorescence, occurring singly at the nodes (in part)
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10b. Spikes usually more than 15 per inflorescence, 2 or more produced from some nodes (i.e., the inflorescence branched)
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11a. Carpellate scales hyaline, with a single vein or 3 veins near the center; culms often wing-angled and easily compressed, usually more than 1 mm wide apically in drying (in part)
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11b. Carpellate scales yellow or brown, with hyaline margins, with 3 veins near the center; stems usually firm and less than 1 mm wide apically in drying
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9b. Leaf sheaths opposite the blade smooth, not rugose
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12a. Perigynia truncate to subcordate at base, tapering from base to apex (in part)
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12b. Perigynia cuneate to rounded at base, widened above the base and then tapering to the apex
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13a. Nodes of the inflorescence with a single spike; leaf sheaths opposite the blade neither red-spotted nor copper-colored (in part)
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13b. Some nodes of the inflorescence, especially the basal ones, with 2 or more spikes (i.e., the inflorescence branched); leaf sheaths opposite the blade dotted with red and/or strongly copper-colored
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Each photo represents one species in this subgroup.