| Lobelia concolor M. Martens & Galeotti, 1842 |
| Lobelia cordifolia Hook. & Arn., 1838 |
| Lobelia cordigera Cav., 1800 |
| Lobelia cornuta L., 1753 |
| Lobelia corymbiformis Rzed., 2016 |
| Lobelia costaricana E. Wimm., 1935 |
| Lobelia costaricana var. magna E. Wimm., 1935 |
| Lobelia cotensis M.E. Jones, 1929 |
| Lobelia crispa Graham, 1826 |
| Lobelia diastateoides McVaugh, 1940 |
| Lobelia diazlunae Rzed. & Calderón, 1997 |
| Lobelia dielsiana E. Wimm., 1926 |
| Lobelia divaricata Hook. & Arn., 1838 |
| Lobelia divergens Rzed., 2016 |
| Lobelia dunnii Greene, 1889 |
| Lobelia ehrenbergii Vatke, 1874 |
| Lobelia ehrenbergii var. ehrenbergii Vatke, 1874 |
| Lobelia ehrenbergii var. gracilens (A. Gray) McVaugh, 1940 |
| Lobelia endlichii (E. Wimm.) T.J. Ayers, 1990 |
| Lobelia erinus L., 1753 |