| 1. Basal leaves compound or deeply lobed (> halfway to blade base), leaflets or primary lobes 3; petals white to pink |
| |
| 2. Hypanthium long-obconic, part fused to ovary generally > free part; ovary > half inferior; petals 716 mm, generally obovate, 3-lobed |
| L. parviflorum |
| 3. Hypanthium ± 2 × longer than wide |
| var. parviflorum |
| 3' Hypanthium 34 × longer than wide |
| var. trifoliatum |
| 2' Hypanthium spheric to bell-shaped, part fused to ovary generally < free part; ovary < half inferior; petals 37 mm, generally ovate, generally 47-lobed |
| |
| 4. Inflorescence 4060 cm; s Channel Islands |
| L. maximum |
| 4' Inflorescence 830 cm; mainland |
| |
| 5. Petal lobes deep, generally 45; inflorescence often with bulblets in axils of lower bracts; seed spiny |
| L. glabrum |
| 5' Petal lobes shallow, 57; inflorescence without bulblets; seed smooth |
| L. tenellum |
| 1' Basal leaves ± shallowly lobed (< halfway to blade base), primary lobes 35; petals white |
| |
| 6. Hypanthium ± long-obconic; ovary generally > half inferior |
| |
| 7. Cauline leaves 13, alternate; petals 3-lobed at tip; seed smooth |
| L. affine |
| 7' Cauline leaves 2, opposite; petals entire to shallowly toothed; seed spiny |
| L. cymbalaria |
| 6' Hypanthium spheric to bell-shaped; ovary < half inferior |
| |
| 8. Petals obovate, lobes 3; hypanthium bell-shaped, base truncate; inflorescence often with bulblets in axils of upper bracts |
| L. heterophyllum |
| 8' Petals ovate-elliptic, entire or lobes or teeth > 3; hypanthium spheric to bell-shaped, base tapered to round; inflorescence bulblets generally 0 |
| |
| 9. Petals spreading, entire or ± evenly toothed or lobed; hypanthium spheric; ovary partly inferior; leaf teeth ± round |
| L. bolanderi |
| 9' Petals ± erect, ± unevenly lobed (generally with teeth near base); hypanthium broadly bell-shaped; ovary superior; leaf teeth ± sharp |
| L. campanulatum
|