Flora of North America species comparison

submersed or emersed; submersed leaves phyllodial, angled abaxially, flattened adaxially, 6.4–35 × 0.5–4 cm; emersed with petiole triangular, 6.5–17 cm, blade linear to linear-oblanceolate, 2.5–17.4 × 0.2–4 cm.

emersed;

petiole 5-winged, 19–85 cm;

blade sagittate, 3–19 × 2.5–11 cm, basal lobes ± equal to remainder of blade.

racemes or panicles, of 1–12 whorls, emersed, 2.5–21 × 1–8 cm;

peduncles 6.5–29.7 cm;

bracts connate more than to equal to ¼ total length, broadly subulate to lanceolate, 20–50 mm, coarse, not papillose; fruiting pedicels spreading, cylindric, 0.5–5 cm.

racemes, of 5–12 whorls, emersed, 10–29 × 3–5 cm;

peduncles 25–105 cm;

bracts distinct or if connate, then less than ¼ total length, lanceolate, 7–30 mm, papery, not papillose; fruiting pedicels spreading to ascending, cylindric, 0.3–2.3 cm.

to 2.3 cm diam.;

sepals recurved to spreading, not enclosing flower;

filaments dilated, shorter than anthers, pubescent;

pistillate flowers pedicellate, without ring of sterile stamens.

to 3 cm diam.;

sepals recurved to spreading, not enclosing flower or fruiting head;

filaments cylindric, longer than anthers, glabrous;

pistillate pedicellate, without ring of sterile stamens.

heads 0.6–1.5 cm diam.;

achenes oblanceoloid, without abaxial keel, 1.5–2.8 × 1.1–1.5 mm, beaked;

faces not tuberculate, abaxial wings 0–1, ± entire, glands 1–2;

beak lateral, erect, 0.2 mm.

heads 1–2.2 cm diam.;

achenes obovoid, without abaxial keel, 2.1–3.2 × 1.4–2.3 mm, beaked;

faces not tuberculate, wings 0–2, ± entire, glands absent;

beak lateral, strongly recurved, 4–17 mm.

= 22.