Apium L.

Tutin, T. G., Heywood, V. H., Burges, N. A., Moore, D. M., Valentine, D. H., Walters, S. M. & Webb, D. A., 1981, Flora Europaea. Volume 2. Rosaceae to Umbelliferae, Cambridge University Press : 351

59. Apium L. 1

Leaves pinnate, or the upper ternate. Sepals minute or absent. Petals whitish, not emarginate; apex sometimes inflexed. Fruit ovoid, or elliptic-oblong, laterally compressed. Ridges usually stout; vittae solitary.

1 Bracteoles absent 1. graveolens 1 Bracteoles 5-7

2 Leaves all with lanceolate to suborbicular, serrate or shallowly lobed segments; bracteoles with white, membranous margins

3 Stem procumbent, rooting at lower nodes, then ascending or erect; peduncle usually shorter than rays; bracts 0-2

2. nodiflorum 3 Stem procumbent and rooting at every node; peduncle usually longer than rays; bracts 3-7 3. repens 2 Lower leaves with segments divided into filiform lobes; bracteoles entirely herbaceous

4 Rays 2(—4); pedicels not thickened in fruit; styles much shorter than stylopodium in fruit 4. inundatum 4 Rays 3-5; pedicels thickened at base in fruit; styles somewhat longer than stylopodium in fruit 5. crassipes