Flora of North America species comparison

submersed, phyllodial, lenticular, to nearly terete, 12–53 × 0.3–0.7 cm;

rare stranded plants without expanded leaf blades.

emersed;

petiole 5-winged, 19–85 cm;

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

racemes, of 2–7 whorls, floating or emersed, to 16 × 4 cm;

peduncles 13.5–28 cm;

bracts connate more than ¼ total length, ovate to lanceolate, 1.5–2 mm, delicate, not papillose; fruiting pedicels spreading to reflexed in flower and fruit, cylindric, 1.5–6.5 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.

1.5–5 cm diam.;

sepals spreading in staminate, appressed to spreading in flower and fruit in pistillate, often enclosing flower or fruiting head;

filaments dilated, longer than anthers, glabrous;

pistillate 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 0.4–0.6 cm diam;

achenes oblanceoloid to obovoid, not abaxially keeled, 1.5 × 1 mm, beaked;

faces not tuberculate, wings absent, glands absent;

beak lateral, erect, 1.1 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.