| Porophyllum porophyllum (L.) Kuntze, 1898 |
| Porophyllum pringlei B.L. Rob., 1893 |
| Porophyllum punctatum (Mill.) S.F. Blake, 1917 |
| Porophyllum purpureum M.E. Jones, 1933 |
| Porophyllum quinqueflorum Brandegee, 1905 |
| Porophyllum rotundifolium M.E. Jones, 1933 |
| Porophyllum ruderale (Jacq.) Cass., 1826 |
| Porophyllum ruderale subsp. macrocephalum (DC.) R.R. Johnson, 1969 |
| Porophyllum ruderale var. macrocephalum (DC.) Cronquist, 1970 |
| Porophyllum ruderale var. ruderale (Jacq.) Cass., 1826 |
| Porophyllum scoparium A. Gray, 1852 |
| Porophyllum seemannii Sch. Bip., 1856 |
| Porophyllum simplex M.E. Jones, 1908 |
| Porophyllum tagetoides (Kunth) DC., 1836 |
| Porophyllum tridentatum Benth., 1844 |
| Porophyllum tridentatum var. crassifolium (S. Watson) I.M. Johnst., 1924 |
| Porophyllum tridentatum var. tridentatum Benth., 1844 |
| Porophyllum vaseyi Greene, 1911 |
| Porophyllum viridiflorum (Kunth) DC., 1836 |
| Porophyllum warnockii R.R. Johnson, 1966 |