| Townsendia exscapa (Richardson) Porter, 1894 |
| Townsendia mexicana A. Gray, 1849 |
| Tragoceros Kunth, 1818 |
| Tragoceros americanum (Mill.) S.F. Blake, 1930 |
| Tragoceros flavicomum DC., 1836 |
| Tragoceros microglossum DC., 1836 |
| Tragoceros schiedeanum Less., 1834 |
| Tragoceros zinnioides Kunth, 1818 |
| Tragopogon L., 1753 |
| Tragopogon porrifolius L., 1753 |
| Tricarpha Longpre, 1970 |
| Tricarpha durangensis Longpre, 1970 |
| Trichaetolepis Rydb., 1915 |
| Trichapium Gilli, 1983 |
| Trichocoroninae R.M. King & H. Rob., 1980 |
| Trichocoronis A. Gray, 1849 |
| Trichocoronis greggii A. Gray, 1852 |
| Trichocoronis rivularis A. Gray, 1849 |
| Trichocoronis sessilifolia (Schauer) B.L. Rob., 1906 |
| Trichocoronis wrightii (Torr. A. Gray) A. Gray, 1849 |