| Navicula accomoda Hust., 1950 |
| Navicula acuminata (Sm.) Ralfs, 1861 |
| Navicula acuta (W. Sm.) O'Meara, 1875 |
| Navicula adhaerens Mereschk., 1901 |
| Navicula agnita Hust., 1955 |
| Navicula alata Ehrenb., 1840 |
| Navicula algida Grunow, 1884 |
| Navicula alpha Cleve, 1893 |
| Navicula ammophila Grunow, 1882 |
| Navicula ammophila var. intermedia Grunow, 1862 |
| Navicula amphibola Cleve, 1891 |
| Navicula anceps (Ehrenb.) Mann, 1907 |
| Navicula angusta Grunow, 1860 |
| Navicula angustata W. Sm., 1853 |
| Navicula antillarum (Cleve & Grunow) Mann, 1907 |
| Navicula apiculata Bréb., 1854 |
| Navicula arcus Ehrenb., 1836 |
| Navicula arenaria Donkin, 1861 |
| Navicula arvensis Hust., 1937 |
| Navicula auriculata Hust., 1944 |