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Section Phacocystis
See list of 14 species in this sectionCarex ×limula T. Fries was reported from ME by Campbell et al. (1995). The specimens that supposedly vouchered this occurrence were all C. bigelowii (all at MAINE!). References: Haines (2000b), Standley et al. (2002).
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1a. At least the lower carpellate scales with the apex prolonged into a conspicuous, usually scabrous, awn [Figs. 99,100]
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2a. Lowest carpellate spike usually drooping on a peduncle (5–) 14–68 mm long; carpellate scales including awns (2.9–) 3.1–20 mm long, pale brown to copper-brown
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3a. Plants colonial from elongate rhizomes; lowermost spike 8–20 mm thick; plants of saline and brackish marshes and strands
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3b. Plants cespitose from short rhizomes; lowermost spike 5–10 mm thick; plants of non-saline wetlands and shorelines
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4a. Lower sheaths glabrous; apex of carpellate scales retuse or less commonly trunctate [Fig. 99]; perigynia obovoid to broad-obovoid (rarely ellipsoid)
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4b. Lower sheaths scabrous with short, stiff hairs; apex of carpellate scales acuminate to truncate (sometimes slightly retuse in C. mitchelliana) [Fig. 100]; perigynia ellipsoid to ovoid
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5a. Apex of carpellate scales acute to acuminate; perigynia smooth or weakly papillose near the apex; achenes with a constriction
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5b. Apex of carpellate scales ± truncate; perigynia densely papillose throughout; achenes without a constriciton
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2b. Lowest carpellate spike ascending to arching on a peduncle 6–20 mm long; carpellate scales including awns 2.5–9 mm long, brown to red-brown or purple-brown
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6a. Perigynia long-papillose, with 2–5 veins on each face; carpellate scales dark brown to purple-brown, with a paler central band 10–33% as wide as the entire scale; achenes dull, with or without folds or constrictions; perigynium beak sometimes with scabrules about the orifice
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6b. Perigynia short-papillose, veinless or obscurely veined; carpellate scales bronze to brown, with a central pale band 33–50% as wide as the entire scale; achenes lustrous, with a fold across one face; perigynium beak without scabrules
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1b. Carpellate scales unawned at the apex, at most with a minute, smooth cusp
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7a. Lowermost spike arching to drooping; perigynium smooth, with a triangular, flat, often twisted, apex
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7b. Lowermost spike erect to ascending; perigynium minutely papillose, with a rounded to acute, only somewhat flattened, plane apex
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8a. Lowest bract of inflorescence exceeding the total height of the inflorescence (often conspicuously so) [Fig. 101]; leaf blades amphistomic
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9a. Leaves 1.5–3.5 mm wide; perigynia with (3–) 5–7 veins on each surface; achenes dull; plants cespitose from short rhizomes; lateral spike entirely carpellate
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9b. Leaves 2.5–8 mm wide; perigynia without veins or with 1–4 obscure (rarely distinct) veins on one surface [Fig. 98]; achenes glossy; plants colonial from elongate rhizomes; usually at least some of the lateral spikes androgynous
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8b. Lowest bract of inflorescence shorter than or equaling the total height of the inflorescence; leaf blades hypostomic (except C. nigra, which has stomates on the adaxial surface)
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10a. Carpellate scales purple-brown to black; stems arising from the center of the previous year’s leaf tufts, surrounded by senescing leaves
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11a. Perigynia with 3–9 veins on each surface, the beak with scabrules about the orifice [Fig. 102]; leaf blades with stomates on the adaxial surface
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11b. Perigynia without veins or with 1–4 obscure (rarely distinct) veins on one surface, the beak lacking scabrules; leaf blades lacking stomates on the adaxial surface
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10b. Carpellate scales pale brown to red-brown; stems arising laterally, not surrounded by the previous year’s leaves
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12a. Lower sheaths not fibrillose; sheaths of stems leaves convex and prolonged at summit; perigynia not spotted with red, with 3–5 veins on each surface
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12b. Lower sheaths splitting into an inconspicuous to prominent ladder-network of fibers [Fig. 103]; sheaths of stem leaves concave at summit; perigynia sometimes red-spotted in apical portion, with 0–5 veins on each face
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13a. Carpellate scales shorter than the perigynia (varying to as long as), acute at the apex; perigynia ovoid, acute to obtuse at the apex, with 0–5 veins on each surface, ascending; stems commonly ± equal in height to the leaves; lower leaf sheaths scabrous
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13b. Carpellate scales longer than the perigynia, acute to acuminate at the apex; perigynia obovoid, rounded at apex, without veins, divergent; stems commonly surpassing the leaves in height; lower leaf sheaths glabrous
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Each photo represents one species in this section.