| Navicula lineola var. perlepida (Grunow) Cleve, 1894 |
| Navicula longa (W. Greg.) Ralfs ex A. Pritch., 1861 |
| Navicula longa var. irregularis Hust., 1955 |
| Navicula lucens Hust., 1942 |
| Navicula lusoria Giffen, 1975 |
| Navicula lyra Ehrenb., 1843 |
| Navicula macilenta (Ehrenb.) Pant., 1889 |
| Navicula maculata (Bailey) A.M. Edwards, 1859 |
| Navicula major (Kütz.) Ehrenb., 1838 |
| Navicula margarita A. Schmidt, 1892 |
| Navicula marina Ralfs, 1861 |
| Navicula mendotia Van Land, 1975 |
| Navicula meniscoides Hust., 1955 |
| Navicula menisculus Schum., 1867 |
| Navicula menisculus var. upsaliensis Grunow, 1880 |
| Navicula meyeri Jasnitzky, 1936 |
| Navicula meyeri var. meyeri Cleve-Euler, 1953 |
| Navicula microstauron (Ehrenb.) Hérib., 1903 |
| Navicula minima Grunow, 1880 |
| Navicula minuscula Grunow, 1880 |