| 1 | Bracteoles deeply pinnatisect, foliaceous; petals c. 0.5 mm long |
| 1' | Bracteoles entire or bifid at apex, not foliaceous; at least some petals 1 mm long or more |
| 2 | Beak of fruit stongly compressed dorsally; fruit 3-5 cm long; bracteoles lanceolate, apex usually 2-lobed or deeply emarginate |
| 2' | Beak of fruit subterete or slightly compressed laterally; fruit 2-3 cm long; bracteoles ovate-ellptic, entire or shortly bifid or emarginate at apex |
| 3 | Umbels 1-2(-3)-rayed; flowers all fertile and hermaphrodite, not markedly radiant; largest petal about 1-1.5 mm long; styles usually less than 0.6 mm long |
| 3' | Umbels 3(-5)-rayed, rays often subdivided into secondary umbels; flowers partly male and sterile, markedly radiant; largest petal often 5 mm long; styles frequently 1.5 mm long |
