| Thalassiosira eccentrica (Ehrenb.) Cleve, 1903 |
| Thalassiosira echinata Sëmina, 1994 |
| Thalassiosira elsayedii G.A. Fryxell, 1975 |
| Thalassiosira endoseriata Hasle & G.A. Fryxell, 1977 |
| Thalassiosira exigua G.A. Fryxell & Hasle, 1977 |
| Thalassiosira ferelineata Hasle & G.A. Fryxell, 1977 |
| Thalassiosira gracilis (G. Karst.) Hust., 1958 |
| Thalassiosira gracilis var. expecta G.A. Fryxell & Hasle, 1979 |
| Thalassiosira gravida Cleve, 1896 |
| Thalassiosira hendeyi Hasle & G.A. Fryxell, 1977 |
| Thalassiosira hyalina (Grunow) Gran, 1897 |
| Thalassiosira intrannula Herzig & G.A. Fryxell, 1986 |
| Thalassiosira lacustris (Grunow) Hasle, 1977 |
| Thalassiosira leptopus (Grunow) Hasle & G.A. Fryxell, 1977 |
| Thalassiosira lineata Jousé, 1964 |
| Thalassiosira lineoides Herzig & G.A. Fryxell, 1986 |
| Thalassiosira lundiana G.A. Fryxell, 1975 |
| Thalassiosira mala Takano, 1965 |
| Thalassiosira mediterranea (Schröd.) Hasle, 1972 |
| Thalassiosira mendiolana Hasle & Heimdal, 1970 |