Flora of North America species comparison

ascending to erect, 10–75 cm, villous.

ascending to erect, villous (hairs jointed), rarely glabrous.

blade linear to lanceolate-ovate, 8–20 × 0.7–3 mm, base not clasping, truncate, margins entire, prominently revolute, apex acute to acuminate, surfaces villous, papillate, not distinctly punctate abaxially.

cauline, sometimes also basal, opposite;

petiole absent, sometimes present on basal leaves;

blade not fleshy, leathery, margins entire or serrate.

axillary, flowers 1 or 2 per node;

bracts present.

0–1 mm;

bracteoles 6–9 mm.

present or absent;

bracteoles present, 2.

calyx lobes 3–7 × 0.5–1 mm;

corolla salverform, 7–16 mm, tube white, veins inconspicuous or pale purple, limb white.

bisexual;

sepals 5, distinct, linear to linear-lanceolate, calyx ± bilaterally symmetric, campanulate;

corolla white, sometimes tinged purple or pink, bilaterally symmetric, bilabiate to bilabiate and personate, tubular to salverform, tube base not spurred or gibbous, lobes 5, abaxial 3, adaxial 2, throat hairy;

stamens 2, medially adnate to corolla, filaments glabrous, pollen sacs parallel to filaments, connective not dilated;

staminodes 0 or 2, minute;

ovary 2-locular, placentation axile;

stigma crateriform.

capsules, dehiscence septicidal, sometimes also loculicidal.

conic, 4–5 × 1.8–2.5 mm.

0.2–0.4 mm.

ca. 200, yellow to brown or black, ovoid to short-cylindric, wings absent.