| | 1. Perennial; receptacle rim 0.5–5 mm; cotyledons generally 2-lobed |
| 2 E. californica |
| | 1' Annual; receptacle rim generally 0–0.3 mm; cotyledons generally entire |
| |
| | 2. Receptacle rim 0.5–5 mm; cotyledons sometimes 2-lobed |
| 2 E. californica |
| | 2' Receptacle rim 0–0.3 mm; cotyledons entire |
| |
| | 3. Leaves generally basal; leaf segments acute; petals yellow; flower bud glabrous |
| |
| | 4. Flower bud generally nodding; seed minutely pitted; petals (10)12–25 mm; Desert |
| E. glyptosperma |
| | 4' Flower bud erect; seed with prominent discontinuous ridges; petals 7–12 mm; Sierra Nevada Foothills, Great Central Valley |
| E. lobbii |
| | 3' Leaves basal and cauline; leaf segments acute or obtuse; petals yellow or orange; flower bud glabrous or hairy |
| |
| | 5. Flower bud generally hairy, nodding; petiole generally hairy |
| |
| | 6. Petals yellow, bases sometimes orange-spotted, 10–15(20) mm; receptacle < 1.5 mm wide |
| E. hypecoides |
| | 6' Petals orange or deep yellow throughout, 15–40 mm; receptacle > 1.5 mm wide |
| E. lemmonii subsp. lemmonii |
| | 5' Flower bud glabrous, nodding or erect; petiole generally glabrous |
| |
| | 7. Flower bud generally nodding; East of Sierra Nevada, Desert |
| |
| | 8. Leaf segments widened to tip, generally obtuse, < 2 mm; leaves grayish or bluish green; petals 3–26 mm; seeds generally oblong to elliptic |
| E. minutiflora |
| | 8' Leaf segments not widened to tip, acute, > 1.5 mm; leaves bright green or yellow-green; petals 8–30 mm; seeds generally round |
| E. parishii |
| | 7' Flower bud generally erect; not Desert |
| |
| | 9. Receptacle obconic, < 2.5 mm wide |
| |
| | 10. Flower bud long-pointed generally > 1/4 bud; plant appearing compact from short lower leaf segments; mainland |
| E. caespitosa |
| | 10' Flower bud blunt or short-pointed < 1/4 bud; plant appearing open from ± long lower leaf segments; Channel Islands |
| E. ramosa |
| | 9' Receptacle barrel-shaped, > 2 mm wide |
| |
| | 11. Petals 20–40 mm, orange or deep yellow; sw Tehachapi Mountain Area, n Western Transverse Ranges |
| E. lemmonii subsp. kernensis |
| | 11' Petals 3–15 mm, yellow; Inner North Coast Ranges, San Francisco Bay Area, Inner South Coast Ranges, eastern Outer South Coast Ranges |
| E. rhombipetala
|