Flora of North America species comparison

ascending to erect, simple or few-branched, 2–12 cm, glabrous 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 linear-lanceolate to oblanceolate, elliptic, or oblong, 4–8(–20) × 1.5–3.5 mm, margins entire, apex obtuse to rounded, 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.

slender, 2–14(–28) mm, length 0.9–2.3 times bract, sparsely to densely glandular-puberulent;

bracteoles 0.

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

bracteoles 0.

sepals connate proximally, calyx distinctly bilaterally symmetric, lobes elliptic-oblanceolate, 3.5–6 mm;

corolla 4–7.5(–9) mm, tube yellow or greenish yellow, veins purple, limb white abaxially, greenish yellow adaxially;

style 1.5–2 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 to ovoid, 3.5–4.7 × 3–4.5 mm.

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

0.5–0.7 mm.

(0.3–)0.4–0.5 mm.

= 18.