Flora of North America species comparison

submersed with elongate internodes, or emersed and procumbent.

of 2 types, vegetative and flowering;

vegetative stems indeterminate, bearing many leaves, glabrous; flowering stems determinate, usually emersed, bearing single leaf, spathe, and terminal inflorescence.

1–9 cm, distal internode 0.5–4 cm.

of 2 types, sessile and petiolate;

stipule marcescent, apex truncate, associated with petiolate leaves only;

sessile leaves submersed or rarely emersed, forming basal rosette or alternate on elongate stem, blade linear to occasionally oblanceolate, base sheathing, margins entire; petiolate leaves floating or emersed, blade cordate, reniform, or ovate.

spicate, 2–8-flowered, elongating in 1 day, usually shorter than spathes, terminal flower sometimes extending beyond spathe apex;

spathes 0.8–5.5 cm, glabrous;

peduncle 0.5–4.2 cm, glabrous.

paniculate, spicate, umbellate, or 1-flowered;

spathes bractlike, folded or clasping, commonly with acute to caudate extension.

opening ca. 3 hours after sunrise, wilting by early afternoon;

perianth white, salverform, tube 5–10 mm, limbs zygomorphic, lobes narrowly elliptic, 3–6.5 mm, distal central lobe with yellow or green region at base, sometimes with distal brown spot;

stamens unequal, lateral stamens 0.9–2.2 mm, filaments linear, pubescent with white multicellular hairs toward apex;

central stamen 2.2–4.7 mm, filament sparsely pubescent with multicellular hairs;

style pubescent with multicellular hairs.

sessile, 3-merous;

perianth with tepals connate proximally, yellow, blue, mauve, or white, tube tubular or funnelform, limb 6-lobed;

stamens 3 or 6, adnate to perianth;

pistils 3-locular, 1 or 3 developing to maturity;

placentation parietal or basal;

ovules 1–many.

capsular or utriculate.

8–14-winged, 0.5–0.9 × 0.3–0.5 mm.

smooth or with longitudinal wings.

leaves forming basal rosette, blade linear to oblanceolate, thin, 2.4–3.7 cm × 3–8 mm.

leaves floating or emersed;

stipule 1–5 cm;

petiole 2–13 cm;

blade reniform, 1–4 × 1–5 cm, length equal to or less than width, apex obtuse.

= 48.