Flora of North America species comparison

submersed and emersed; submersed leaves absent or phyllodial, flattened, to 17 × 2 cm; emersed leaves with petiole triangular, 21–55 cm, blade hastate to sagittate, 2.5–17.5 × 0.6–22 cm, lobes longer than or equal to remainder of blade.

emersed;

petiole triangular, 10–40 cm;

blade sagittate, 4.5–10 × 0.2–2 cm, basal lobes ± equal to remainder of blade.

racemes or panicles, of 1–15 whorls, floating or emersed, 1.5–28 × 1.5–15 cm;

peduncles 15–47 cm;

bracts distinct or connate less than ¼ total length, lanceolate to elliptic, 4–34 mm, delicate, not papillose; fruiting pedicels recurved, club-shaped, 0.5–4.2 cm.

racemes, of 2–4 whorls, emersed, 5–14 × 2–4 cm;

peduncles 20–38 cm;

bracts distinct or if connate, then less than ¼ total length, lanceolate, 5–25 mm, not papillose; fruiting pedicels spreading, cylindric, 1.5–3.5 cm.

2–5 cm diam.;

sepals spreading in staminate, erect in pistillate, enclosing flower or fruiting head;

filaments cylindric, longer than anthers, glabrous; pistillate pedicellate, with or without ring of sterile stamens.

to 30 mm diam.;

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

filaments linear, longer than to equal length of anther, glabrous; pistillate pedicellate, without ring of sterile stamens.

heads 1.2–2.1 cm diam.;

achenes oblanceoloid, not abaxially keeled, 2–4.3 × 0.7–1.5 mm, beaked;

faces not tuberculate, wings absent, glands 1;

beak lateral, horizontal, 0.4–0.8 mm.

heads 1–1.8 cm diam.;

achenes cuneate to obovoid, without abaxial keel, 2.4–4 × 1.5–3.8 mm, beaked;

faces not tuberculate, wings 1–3, ± entire, glands 1–2;

beak lateral, obliquely ascending, (0.7–)1–2.1 mm.

= 22.