Flora of North America species comparison

ascending to erect, simple or few-branched, 4–50 cm, glabrous or glabrate proximally, glabrous or glandular-puberulent distally.

erect, simple or few-branched, (7–)9–21(–29) cm, glabrous or glabrate proximally, glabrate or glandular-puberulent distally.

blade lanceolate to elliptic or oblong-obovate, 15–70 × 5–25 mm, margins entire or with 1–4 pairs of blunt or sharp teeth distally, apex obtuse to acute, surfaces glabrous.

dimorphic, submersed basal and clustered, floating paired at ends of branches to 70 mm, blade of submersed lanceolate to oblanceolate or oblong, 1–7 × 0.5–3 mm, margins entire, apex obtuse to acute, surfaces glabrous, blade of floating elliptic to ovate or nearly round, 3–10 × 2–9 mm, margins entire, apex obtuse to rounded or retuse, surfaces glabrous.

stout, 1–12 mm, length 0.1–0.3 times bract, glabrous or sparsely glandular-puberulent;

bracteoles 2, 2–6 mm.

stout, 0.1–3 mm, length less than 0.1 times bract, glabrous;

bracteoles 0.

sepals distinct, linear-lanceolate to lanceolate or oblong, 4–7 mm;

corolla 8–15 mm, tube greenish white to greenish yellow or yellow, veins purple or brownish purple, limb white, sometimes tinged lavender;

style 2–4 mm.

sepals connate proximally, calyx lobes obovate to oblong, 0.7–1 mm;

corolla 3–4 mm, tube and limb white tinged pink or purple, veins lavender or purple;

style 0.5–1 mm.

subglobular, (3–)4–9 × 4–8 mm.

bilaterally symmetric, obcordiform, 2–3 × 3–4 mm.

0.7–0.8 mm.

(0.3–)0.4–0.5 mm.

= 16.

= 18.