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Section Laxiflorae
See list of 8 species in this sectionColor of the basal portion of the plant is critical for identification. Therefore, complete collections are a must. Reference: Bryson and Naczi (2002b).
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1a. Shoots anthocyanic at the base, ranging from a slight tinging of the brown background to a strong purple coloration
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2a. Vegetative leaf blades 10–52 mm wide; blades of upper bracting leaves spathe-like, lanceolate to narrow-lanceolate, 4–16 mm wide; carpellate scales ± truncate and apiculate at the apex, lacking awns; flowering stems 2–2.4 mm wide, distinctly winged (in part)
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2b. Vegetative leaf blades 1–12 mm wide; blades of upper bracting leaves not spathe-like, mostly linear, 0.5–6 mm wide; carpellate scales truncate to acuminate at the apex, usually with awns; flowering stems 0.5–2 mm wide, unwinged or with obscure wing angles
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3a. Longest carpellate spike 19–33 mm long, the basal internode (i.e., the distance between the lowest and next apical flowers) 3.5–14 mm [Fig. 93]; perigynia varying from remote to loosely imbricate, with a nearly straight to bent beak; upper portion of flowering stem ± smooth on the angles
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3b. Longest carpellate spike 11–21 mm long, with a basal internode of 1.1–3.2 (–4.8) mm [Fig. 91]; perigynia closely imbricate, with an abruptly bent beak; upper portion of flowering stem scabrous on the angles
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1b. Shoots lacking anthocyanic pigments at the base, mostly pale brown to brown
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4a. Vegetative leaves 10–52 mm wide; blades of upper bracting leaves spathe-like, lanceolate to narrow-lanceolate, 4–16 mm wide; flowering stems 2–2.4 mm wide, distinctly winged (in part)
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4b. Vegetative leaves 3–26 mm wide; blades of upper bracting leaves not spathe-like, mostly linear, 0.8–8 mm wide; flowering stems 0.5–2 mm wide, unwinged or with obscure wing angles
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5a. Perigynia with only 2 evident lateral veins, the remaing 6–16 veins faint; anthers (1.4–) 1.6–2 (–2.4) mm long
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5b. Perignynia with 22–39 distinct veins; anthers (2–) 2.4–4 (–4.5) mm long (as short as 1.8 mm in C. blanda)
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6a. Carpellate spikes 6–20 mm long, with crowded perigynia, the basal internode (i.e., the distance between the lowest and next apical flower) 0.9–2.4 mm long [Fig. 91]; upper portion of flowering stem scabrous on the angles
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7a. Perigynia tapering to a straight or merely outcurved beak 0.5–1.7 mm long; staminate scales 3.2–4.2 ×1–1.2 mm
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7b. Perigynia abruptly tapering to a short, bent beak 0.2–0.5 mm long; staminate scales 1.8–3.2 ×1.4–1.8 mm
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6b. Carpellate spikes 9–62 mm long, the longest usually more than 18 mm, with approximate but not crowded perigynia, the basal internode (2.2–) 2.8–7.5 mm long [Fig. 93]; upper portion of flowering stem smooth on the angles
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8a. Perigynia 2.6–3.8 mm long, usually more abruptly tapered in the apical portion than in the basal portion; staminate spikes 12–26 mm long
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8b. Perigynia 3.4–5 mm long, usually ± evenly tapered in the apical and basal portions; staminate spikes 22–36 mm long
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Each photo represents one species in this section.