| 1. Petals red; staminodes pink; sepals lanceolate, ciliate; stigmas ± = styles in width |
| L. grandiflorum |
| 1' Petals blue, white, yellow, or orange; staminodes white; sepals linear to ovate, margins generally glabrous or gland-toothed; stigmas > styles in width |
| |
| 2. Petals yellow to orange; margins of leaves, bracts, and sepals gland-toothed; styles fused to near tip |
| L. puberulum |
| 2' Petals blue to white; margins of leaves, bracts, and sepals generally entire, glabrous; styles free or fused only near base |
| |
| L. lewisii |
| 4. Petals 67 mm; styles < 6 mm |
| var. alpicola |
| 4' Petals 1015 mm; styles generally > 6 mm |
| var. lewisii |
| |
| 5. Petals 810 mm; pedicels 518 mm; sepals 46 mm; fruit 45 mm |
| L. bienne |
| 5' Petals 1015 mm; pedicels 2025 mm; sepals 610 mm; fruit 710 mm |
| L. usitatissimum
|