| Kyrsteniopsis nelsonii (B.L. Rob.) R.M. King & H. Rob., 1971 |
| Kyrsteniopsis perpetiolata (R.M. King & H. Rob.) B.L. Turner, 1998 |
| Kyrsteniopsis spinaciifolia (DC.) B.L. Turner, 1998 |
| Lacinaria Hill, 1762 |
| Lactuca L., 1753 |
| Lactuca brachyrrhyncha Greenm., 1899 |
| Lactuca graminifolia Michx., 1803 |
| Lactuca graminifolia var. arizonica McVaugh, 1972 |
| Lactuca graminifolia var. graminifolia Michx., 1803 |
| Lactuca graminifolia var. mexicana McVaugh, 1972 |
| Lactuca intybacea Jacq., 1784 |
| Lactuca ludoviciana (Nutt.) Riddell, 1835 |
| Lactuca pulchella (Pursh) DC., 1838 |
| Lactuca sativa L., 1753 |
| Lactuca scariola L., 1763 |
| Lactuca serriola L., 1756 |
| Lactucinae Cass. ex Dumort., 1827 |
| Laennecia Cass., 1822 |
| Laennecia chihuahuana G.L. Nesom, 1990 |
| Laennecia confusa (Cronquist) G.L. Nesom, 1990 |