| 1 | Plant perennial with a tuberous rhizome; flowers large, petals more than 1 cm long; leaves all basal |
| 1' | Plants annual; flowers small, petals less than 1 cm long; stems leafy |
| 2 | Sepals spreading; petals with a short claw; mericarps breaking away at maturity with a portion of the beak attached |
| 2' | Sepals erect more or less connivent; petals with a long slender claw; mericarps breaking away at maturity without a portion of beak attached
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| 3 | Lower leaves divided to about half way into oblong-cuneate, shortly lobed divisions |
| 3' | Lower leaves divided almost to base into deeply lobed or pinnatifid divisions |
| 4 | Mericarps glabrous, wrinkled or ridged; petals deeply emarginate or bifid, to about 5 mm long |
| 4' | Mericarps smooth, pubescent |
| 5 | Petals distinctly emarginate, pale purple, up to 4 mm long; usually outer stamens without anthers |
| 5' | Petals entire or indistinctly emarginate, bright pink or rosy-purple, c. 5-7 mm long; all stamens with anthers |
| 6 | Peduncles 5-10 mm long; pedicels 10-15 mm long; mericarps glandular-pubescent |
| 6' | Peduncles 20-90 mm long; pedicels 25-50 mm (or more) long; mericarps subglabrous or sparsely strigose |
| 7 | Leaves palmately divided to base, not conspicuously glossy; sepals strigose-glandular externally, without transverse wrinkles |
| 7' | Leaves not divided to base, often glossy; sepals glabrous, transversely wrinkled |
