| Trichocoronis sessilifolia (Schauer) B.L. Rob., 1906 |
| Trichocoronis wrightii (Torr. A. Gray) A. Gray, 1849 |
| Trichocoryne S.F. Blake, 1924 |
| Trichocoryne connata S.F. Blake, 1924 |
| Trichoptilium A. Gray, 1859 |
| Trichoptilium incisum (A. Gray) A. Gray, 1859 |
| Trichospira Kunth, 1818 |
| Trichospira biarista Less., 1829 |
| Trichospira menthoides Kunth, 1818 |
| Trichospira prieurei DC., 1836 |
| Trichospira pulegium Mart. ex DC., 1836 |
| Trichospira verticillata (L.) S.F. Blake, 1915 |
| Trichospirinae Less., 1831 |
| Trichostemma Cass., 1827 |
| Trichostephium Cass., 1828 |
| Tridax L., 1753 |
| Tridax accedens S.F. Blake, 1943 |
| Tridax balbisioides (Kunth) A. Gray, 1879 |
| Tridax bicolor A. Gray, 1849 |
| Tridax bilabiata A.M. Powell, 1963 |