| Navicula pygmaea Kütz., 1849 |
| Navicula quarnerensoides Hust., 1961 |
| Navicula radiosa Kütz., 1844 |
| Navicula radiosa var. radiosa Kütz., 1844 |
| Navicula radiosa var. tenella (Bréb.) Van Heurck, 1885 |
| Navicula radiosafallax Lange-Bert., 1993 |
| Navicula radiostriata Hust., 1936 |
| Navicula recens (Lange-Bert.) Lange-Bert., 1985 |
| Navicula regularis Hust., 1955 |
| Navicula reinhardtii (Grunow) Grunow, 1880 |
| Navicula retusa Bréb., 1854 |
| Navicula rhynchocephala Kütz., 1844 |
| Navicula rhynchocephala var. brevis Grunow, 1860 |
| Navicula rhynchocephala var. constricta Huds., 1954 |
| Navicula rhynchocephala var. elongata Grunow, 1860 |
| Navicula rhynchocephala var. rhynchocephala Kütz., 1844 |
| Navicula rhynchotella Lange-Bert., 1993 |
| Navicula riediana Lange-Bert. & Rumrich, 2000 |
| Navicula rivulorum Lange-Bert. & Rumich, 2000 |
| Navicula rostellata Kütz., 1844 |