Perennial; stems solitary or few, glabrous, 3-7 dm tall; leaves entire, opposite, basal leaves elliptic to lanceolate, stem leaves much reduced, 2-4 pairs, sessile, lanceolate; inflorescence slightly glandular, more orless secund, usually as much as ...
Perennial herb; stems gray-green, glabrous, up to 70 cm tall, branching from the base; leaves opposite, entire, slightly thickened, basal leaves short petiolate, ovate to elliptic, to 12 cm long, stem leaves smaller, sessile, ovate to lanceolate; flo...
Perennial herb; stems 40-100 cm tall; leaves opposite, thick, to 6 cm long and 5 cm wide, heart-shaped; inflorescence secund (one-sided), the cymules paired, well spaced, 2-flowered; calyx 4-6 mm long; corolla 26-30 mm long, red, narrowed at the mout...
Shrub forming a prostrate mat, large hedge, or thicket several centimeters to 3 m tall (typically less than 8 dm tall); leaves petiolate, 1.0-4.5 cm long, 0.5-2.2 cm wide, broadly elliptic to ovate, with rounded or cordate bases, margins finely serra...