Flora of North America species comparison

present.

present.

compressed, without spots, 10–35 cm;

glands absent.

terete, without spots, to 100 cm;

glands absent.

absent.

absent.

both submersed and floating or floating absent, ± spirally arranged.

submersed, conspicuously 2-ranked, sessile, stiffish;

stipules persistent, conspicuous, adnate to base of blade about ± ¼ length of stipule, connate, greenish brown to white, ligulate, 0.5–2 cm, fibrous, shredding at tip, apex obtuse;

blade dark green to reddish green, linear to lanceolate, not arcuate, 2–7(–12) cm × 3–4(–8) mm, base rounded, with basal lobes, not clasping, margins minutely spinulose to serrulate, not crispate, apex not hoodlike, acute, lacunae absent;

veins 20–60, fine.

petiolate;

petioles continuous in color to apex, 0.7–0.8 cm;

blade adaxially light green, obovate to elliptic, 0.8–1.6 cm × 3–8.5 mm, base acute, apex round to acute;

veins 3–7.

sessile, lax;

stipules persistent to deliquescent, inconspicuous, convolute, adnate to blade ½ stipule length, light brown to red-brown, ligulate, 1.5–2.3 cm, not fibrous, not shredding at tip, apex obtuse;

blade red-brown to light green, linear, often arcuate, 1–1.3 cm × 0.1 mm, base slightly tapering, without basal lobes, not clasping, margins entire, not crispate, apex not hoodlike, acute, lacunae present, 1–2 rows each side midrib;

veins 1.

unbranched;

peduncles dimorphic, submersed axillary, recurved, clavate, 3–5 mm, emersed axillary or terminal, erect to slightly recurved, clavate, 6–15 mm;

spikes dimorphic, submersed capitate, 2–3 mm, emersed cylindric, 5–9.7 mm.

often branched;

peduncles not dimorphic, axillary, erect, cylindric, 3–5(–7) cm;

spikes not dimorphic, moniliform (i.e., beaded), 7–20 mm.

sessile, greenish brown, orbicular, compressed, abaxially winged, laterally winged, 1–1.5 × 0.9–2 mm, lateral wings with sharp points;

beak present, erect, 0.1 mm;

sides without basal tubercles;

embryo with more than 1 full spiral.

stipitate, brown, obliquely obovoid, turgid, abaxially and laterally keeled, 3–4(–5) × 2(–3.3) mm, lateral keels without points;

beak erect, recurved at apex, 0.7–0.9 mm;

sides without basal tubercles;

embryo with less than 1 full spiral.

= 52.