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Section Hymenochlaenae
See list of 9 species in this sectionBecause color of the basal portion of the plant is important, complete collections are recommended for confident identification. Reference: Waterway (2002).
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1a. Uppermost spike usually gynecandrous
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2a. Perigynia with 2 prominent, marginal veins, the remaining veins absent or obscure, without red dots; basal leaf sheaths green to green-brown, sometimes with a slight suffusion of anthocyanin
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2b. Perigynia with 2 prominent, marginal veins and 7–15 additional, distinct veins, often red-dotted; basal leaf sheaths suffused with dark red to purple-brown
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3a. Perigynia 4.5–6 mm long, becoming dull orange-brown at maturity; carpellate scales with conspicuous awns 2.5–3 mm long
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3b. Perigynia 2–5 mm long, not becoming orange-brown; carpellate scales acute to cuspidate or with a short awn shorter than 1 mm
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4a. Lateral spikes gynecandrous, the basal 1 or 2 flowers staminate, borne on elongate peduncles usually exceeding the length of the associated spike, 4–6 mm thick; perigynia 3.5–5 mm long, abruptly tapering to a short beak
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4b. Lateral spikes unisexual and carpellate, usually borne on peduncles that are shorter than or equal to the length of the associated spike, 2–3.5 mm thick; perigynia 2–3.7 mm long, tapering to a beakless apex
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5a. Leaf sheaths glabrous; leaf blades 3–9 mm wide
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5b. Leaf sheaths pubescent; leaf blades 1.5–3 mm wide
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1b. Uppermost spike usually unisexual and staminate
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6a. Basal leaf sheaths brown, those of previous years persisting as abundant, fibrous remains; perigynia abruptly tapered to a long, tubular beak nearly as long as the perigynium body
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6b. Basal sheaths red-purple, those of previous years not fibrous or only inconspicuously so; perigynia gradually tapered to a beak obviously shorter than the perigynium body
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7a. Leaf blades pubescent; carpellate spikes 8–25 ×4–5 mm; perigynia with 2 prominent lateral veins and 5–7 additional, finer veins
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7b. Leaf blades glabrous; carpellate spikes 25–80 ×2–3 mm; perigynia with 2 prominent lateral veins and 10–20 additional, finer veins
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8a. Perigynia fusiform to narrow-ellipsoid, 5–9.5 mm long; achene elevated above base of perigynium on a stipe 0.5–1.5 mm long; leaf blades 2–5 (–7) mm wide
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8b. Perigynia ellipsoid-ovoid, 3–5 mm long; achene sessile at base of perigynium; leaf blades 3–10 (–13) mm wide
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Show photos of:
Each photo represents one species in this section.