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Section Stellulatae
See list of 7 species in this sectionDue to differences in the shape of perigynia within a spike, it is best to examine those near, but not at, the base of the spike. Reference: Reznicek (2002b).
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1a. Spikes usually 1 per stem; anthers (2–) 2.2–3.6 mm long; leaf blades involute
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1b. Spikes 2 or more per stem; anthers 0.6–2.2 (–2.3) mm long; leaf blades flat or folded
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2a. Beak of perigynium with smooth margins
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2b. Beak of perigynium at least sparsely ciliate-serrulate on the margins
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3a. Plants subdioecious, the spikes all or nearly all of a single sex on each stem (rarely with entirely carpellate and entirely staminate spikes on the same plant); uppermost spike either entirely staminate or entirely carpellate or mostly carpellate with as many as 3 staminate flowers at the base (i.e., lacking a prolonged, basal staminate portion); anthers (1–) 1.2–2.2 (–2.3) mm long
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3b. Plants monoecious, at least the uppermost spike clearly bisexual; uppermost spike gynecandrous, never entirely staminate, usually with a prolonged, slender base of 2–21 staminate flowers; anthers 0.6–1.6 (–2) mm long
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4a. Widest leaves 2.8–5 mm wide
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5a. Perigynia broad-ovate to suborbicular, 1.5–3 mm wide, 1–1.7 times as long as wide (in part)
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5b. Perigynia ovate to broad-ovate, (1.25–) 1.4–2 (–2.1) mm wide, (1.4–) 1.6–2.5 times as long as wide
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4b. Widest leaves 0.8–2.7 mm wide
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6a. Perigynia (2.6–) 2.9–3.6 (–4) mm long, 1.8–3.2 times as long as wide, with a long beak (0.85–) 0.95–2 mm long and (0.4–) 0.45–0.86 times as long as the body of the perigynium
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6b. Perigynia 1.9–3 (–3.3) mm long, (1.15–) 1.3–2 (–2.2) times as long as wide, with a short beak 0.4–0.95 mm long and 0.18–0.5 (–0.63) times as long as the body of the perigynium
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7a. Perigynia convexly tapered in the apical portion, forming shoulders below the beak, veinless or with as many as 6 faint veins adaxially, with many, fine serrations on the beak
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7b. Perigynia gradually or concavely tapered in the apical portion (i.e., without shoulders), with 1–10 veins adaxially, with fewer and coarser serrations on the beak (in part)
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Show photos of:
Each photo represents one species in this section.