| Porophyllum amplexicaule Engelm. ex A. Gray |
Accepted |
12 |
| Porophyllum calcicola B. L. Rob. & Greenm. |
Accepted |
12 |
| Porophyllum coloratum (Kunth) DC. |
Accepted |
12 |
| Porophyllum gracile Benth. |
Accepted |
24 |
| Porophyllum greggii A. Gray |
Accepted |
36 |
| Porophyllum lanceolatum DC. |
Accepted |
22 |
| Porophyllum linaria (Cav.) DC. |
Accepted |
12 |
| Porophyllum punctatum (Mill.) S. F. Blake |
Accepted |
12 |
| Porophyllum pygmaeum D. J. Keil & Morefield |
Accepted |
12 |
| Porophyllum ruderale (Jacq.) Cass. |
Accepted |
22 |
| Porophyllum ruderale subsp. macrocephalum (DC.) R. R. Johnson |
Accepted |
11 |
| Porophyllum scoparium A. Gray |
Accepted |
12 |
| Porophyllum tridentatum Benth. |
Accepted |
15 |
| Porophyllum viridiflorum (Kunth) DC. |
Accepted |
11 |
| Porophyllum zimapanum B. L. Turner |
Accepted |
12 |
| Porophyllum brevifolium (Hook. & Arn.) Malme |
Unresolved |
22 |
| Porophyllum amplexicaule Engelm. |
Synonym of Porophyllum amplexicaule Engelm. ex A. Gray |
12 |
| Porophyllum tridentatum var. crassifolium (S. Watson) I. M. Johnst. |
Synonym of Porophyllum crassifolium S. Watson |
15 |
| Porophyllum ochroleucum Rydb. |
Synonym of Porophyllum gracile Benth. |
24 |
| Porophyllum ervendbergii A. Gray |
Synonym of Porophyllum punctatum (Mill.) S. F. Blake |
12 |
| Porophyllum nelsonii B. L. Rob. & Greenm. |
Synonym of Porophyllum punctatum (Mill.) S. F. Blake |
12 |
| Porophyllum ruderale subsp. ruderale |
Synonym of Porophyllum ruderale (Jacq.) Cass. |
22 |
| Porophyllum macrocephalum DC. |
Synonym of Porophyllum ruderale subsp. macrocephalum (DC.) R. R. Johnson |
11 |
| Porophyllum ruderale subsp. macrocephalum |
Synonym of Porophyllum ruderale subsp. macrocephalum (DC.) R. R. Johnson |
11 |
| Porophyllum ruderale var. macrocephalum (DC.) Cronquist |
Synonym of Porophyllum ruderale subsp. macrocephalum (DC.) R. R. Johnson |
11 |