| Senecio ampullaceus Hook., 1836 |
| Senecio anacletus Greene, 1901 |
| Senecio andrieuxii DC., 1838 |
| Senecio angulifolius DC., 1837 |
| Senecio angulifolius var. ingens Greenm., 1914 |
| Senecio anisophyllus Klatt, 1888 |
| Senecio aphanactis Greene, 1888 |
| Senecio arborescens Steetz, 1854 |
| Senecio argutus Kunth, 1820 |
| Senecio aschenbornianus Schauer, 1847 |
| Senecio axillaris Klatt, 1882 |
| Senecio barba-johannis DC., 1837 |
| Senecio barkleyi B.L. Turner, 1985 |
| Senecio bartlettii Greenm., 1950 |
| Senecio bellidifolius Kunth, 1820 |
| Senecio billieturneri T.M. Barkley, 1989 |
| Senecio bombycopholis Bullock, 1937 |
| Senecio brachyanthus Greenm., 1914 |
| Senecio bracteatus Klatt, 1888 |
| Senecio burchellii DC., 1838 |