Key to Cultivated and Wild Eranthis

Key to Cultivated and Wild Taxa, Draft

1. Flower petiolate, terrestrial storage organ a tuber, globose or subglobose (section Shibateranthis): 2
+ Flower sessile, terrestrial storage organ a rhizome, oblong, creeping: 9

2. Sepals white: 3
+ Sepals yellow: Eranthis longistipitata

3. Sepals overlapping or nearly so, 10-22 mm long, ovate or ovate-oblong: 4
+ Sepals not overlapping or nearly overlapping, 7-10 mm long, elliptic to oblong: 5

4. Petals distally bifid, Y-shaped; bract lobe pinnatifid: Eranthis pinnatifida
+ Petals funnel formed, distally not Y-shaped; bract lobe linear, entire: Eranthis byunsanensis

5. Pedicel pubescent or glandular; follicles 6-9, short petiolate, pubescent or glandular: 6
+ Pedicel glabrous, follicles 4-9, sessile or short petiolate, glabrous: 7

6. (Pedicel), peduncle and follicles with fine white glandular hair or pubescence; bracts coppery on emergence, flower often lateral: Eranthis stellata
+ Pedicel, peduncle and follicles in sutures with short yellow glandular hair; bracts pale green on emergence, flower often erect: Eranthis sibirica

7. Follicles 4-5, sessile; bract lobes linear; petals funnelform with bifid apex: Eranthis albiflora
+ Follicles 4-9, stalked; bract lobes ovate; petals bifurcate: Eranthis lobulata

9. Bracts mid green on emergence, broad dissected, sepals yellow: Eranthis hyemalis
+ Bracts tinged copper on emergence, finely dissected; sepals shiny golden yellow: Eranthis cilicica

This key is mainly based on own observations, but also:
E. pinnatifida versus E. byunsanensis: Byung Yun Sun et al: A New Species of Eranthis (Ranunculaceae) from Korea: E. byunsanensis. Korean Journal of Plant Taxonomy, Vol 23, No 1, p. 21-26.
E. stellata versus E. sibirica: Flora of the USSR, Vol 5 p. 48-50.
E. albiflora versus E. lobulata: Flora of China