Flora of North America species comparison

prostrate, ascending, erect, or spreading, glabrous.

cauline, opposite;

petiole present;

blade not fleshy, not leathery, margins weakly or sharply serrate.

axillary, flowers solitary;

bracts present.

present;

bracteoles smaller than calyx lobes, not surrounding calyx of flowers they subtend.

bisexual;

sepals 5, proximally connate, calyx bilaterally symmetric, campanulate, lobes ovate, outer lobes ± as wide as inner;

corolla white or lemon yellow with purple or reddish veins in throat, bilaterally symmetric, weakly bilabiate, campanulate [salverform], tube base not spurred or gibbous, throat not densely pilose internally, lobes 5, abaxial 3, adaxial 2, abaxial lip projecting to spreading;

stamens 4, medially or distally adnate to corolla, didynamous, filaments glabrous;

staminode 0;

ovary 2-locular, placentation axile;

stigma 2-lobed.

capsules, dehiscence septicidal, slightly loculicidal at apex.

40–80, black or brown, angled, wings absent.