Flora of North America species comparison

obvious.

present.

terete, without spots, 10–80 cm.

compressed, without spots, 5–40 cm;

glands absent.

present, in axils of old leaves and from disintegrating branches, fusiform, 0.7–2 cm, leaves spreading to ascending.

absent.

submersed, ± spirally arranged, flaccid, sessile;

stipules deliquescent, inconspicuous, convolute, free from blade, pale green, not ligulate, 0.5–1.2 cm, not fibrous, not shredding at tip, apex obtuse;

blade pale green, linear, not arcuate, 1.8–6.5 cm × 0.1–0.5 mm, base slightly tapering, without basal lobes, not clasping, margins entire, not crispate, apex not hoodlike, extremely attenuate, bristly, lacunae present, each side of midvein to margins;

veins 1.

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

petiolate;

petioles continuous in color to apex, 5–25 mm;

blade adaxially light green, oblong to obovate, 0.7–—3.5 cm × 2–13 mm, base tapered to rounded, apex obtuse, rounded;

veins 5–15.

sessile, lax;

stipules persistent to deliquescent, inconspicuous, convolute, adnate to blade for ½ stipule length, reddish brown to light green, ligulate, 2–12 mm, not fibrous, not shredding at tip, apex obtuse;

blade red-brown to light green, linear, not arcuate, 0.8–8 cm × 0.5–2 mm, base slightly tapering, without basal lobes, not clasping, margins entire, not crispate, apex not hoodlike, obtuse to acute, lacunae present, a broad band each side of midvein;

veins 1–3.

unbranched, emersed;

peduncles not dimorphic, terminal, ascending, somewhat clavate, (3–)5–25 cm;

spikes not dimorphic, capitate, 5–12 mm.

unbranched;

peduncles dimorphic, submersed axillary, recurved, clavate, 0.5–3 mm, emersed axillary or terminal, erect to recurved, slightly clavate, 4–27 mm;

spikes dimorphic, submersed capitate, 2–5 mm, emersed ellipsoid to cylindric, 4–13 mm.

sessile, light green, round-obovoid or nearly orbicular, compressed, abaxially and laterally keeled, 2–3 × 1.7–2.8 mm, lateral keels without sharp point;

beak erect, 0.5 mm;

sides without basal tubercles;

embryo with less than 1 full spiral.

sessile, greenish brown, somewhat orbicular, compressed, abaxially winged, laterally winged, 4–13 × 1.3–2.4 mm, lateral wing with blunt tips;

beak absent;

sides without basal tubercles;

embryo with more than 1 full spiral.

apparently unknown not available.