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| 1 Leaves sessile or nearly so, the petioles 0-3 mm long; flowers distinctly 4-ranked; staminodes with purple tips; corolla purple |
| 1 Leaves petiolate, the petioles 2-40 mm long; flowers less distinctly 4-ranked; staminodes with white, green, or pinkish tips; corolla purple or white. |
..2 Petioles (2-) 10-40 mm long; leaf blade rounded or truncate at the base; leaf blades averaging ca. 2× as long as wide, 4-8 cm wide; staminodes with white to light pink tips; corolla purple; inflorescence bracts 2-7 mm long |
| ..2 Petioles 1-15 mm long; leaf blade cuneate at the base; staminodium white or green; leaf blades averaging 3× (or more) as long as wide, 1-6 cm wide; corolla purple or white; inflorescence bracts 4-23 mm long. |
| ....3 Corolla white (or tinged with purple, pink, or green near the mouth); staminodes with green tips; palate white-bearded (rarely greenish-yellow-bearded) |
| ....3 Corolla pink or purple throughout; staminodes with white tips (rarely with green or purple tips); palate yellow-bearded (rarely white-bearded). |
| ......4 Staminodes 4-8 (-12) mm long; calyx lobes densely ciliate; [KY westward] |
| ......4 Staminodes (6-) 8-12 (-14) mm long; calyx lobes glabrous or sparsely ciliate; [more widespread in our area]. |
| ........5 Lower corolla lobes 12-15 (-16) mm long; mid-cauline leaves (6-) 8-20 cm long; [Southern Appalachians] |
| ........5 Lower corolla lobes (12-) 15-19 mm long; mid-cauline leaves 5.3-8 (-12) cm long; [mainly Coastal Plain] |