Flora of North America species comparison

1–several, clustered, terete or distally 4-ridged but not angled or winged, 0.8–6 dm, branching all or mostly alternate.

single, terete or slightly 4-ridged but not angled or winged, 1.5–5(–6.5) dm, branching opposite or alternate.

basal absent at flowering time, internodes between cauline leaves mostly 1.25+ times as long as subtending leaves;

blade elliptic- or oblong-lanceolate, 1.5–7 cm × 4–12(–16) mm.

cauline and often also basal present at flowering time;

basal blades widely oblong-spatulate;

cauline blades abruptly differentiated, linear, 1–10 cm × 1–3 mm.

open, few-flowered monochasia or solitary flowers at ends of branches;

pedicels 10–90(–110) mm.

flowers solitary or in dense, few-flowered clusters, sessile.

7–12(–14)-merous;

calyx tube obconic to campanulate, 1.5–4 mm, mid- and commissural veins about equally prominent, 4-ridged;

lobes linear to oblong-lanceolate or occasionally narrowly spatulate or ± foliaceous, 4–20 mm;

corolla purplish pink or rarely white, eye yellow, projections of eye into corolla lobes oblong, sometimes shallowly 3-lobed, usually with a red border, tube (3–)4–8 mm, lobes oblanceolate to narrowly spatulate-obovate, (10–)12–25 × 3–11 mm, apex rounded to subacute;

anthers coiling circinately.

7–12-merous;

calyx tube widely campanulate, 3–8 mm, not ridged, lobes setaceous, 3–17 mm;

corolla pink, eye greenish yellow, projections of eye into corolla tube oblong, without a border, tube 6–10 mm, lobes oblanceolate to narrowly spatulate-obovate, 12–30 × 4–11 mm, apex rounded to obtuse;

anthers slightly twisting helically, not coiling circinately.

 = 34 + 8B.

 = 28.