| Shionodiscus A.J. Alverson, S.H. Kang & E.C. Theriot, 2006 |
| Shionodiscus bioculatus (Grunow) A.J. Alverson, S-H. Kang & E.C. Theriot, 2006 |
| Shionodiscus endoseriatus (Hasle & G.A. Fryxell) A.J. Alverson, S-H. Kang & E.C. Theriot, 2006 |
| Shionodiscus gracilis (Karsten) A.J. Alverson, S-H. Kang & E.C. Theriot, 2006 |
| Shionodiscus gracilis var. expectus (VanLandingham) A.J. Alverson, S-H. Kang & E.C. Theriot, 2006 |
| Shionodiscus oestrupii (Ostenf.) A.J. Alverson, S.H. Kang & E.C. Theriot, 2006 |
| Shionodiscus oestrupii var. venrickiae (G.A. Fryxell & G.R. Hasle) A.J. Alverson, S.H. Kang & E.C. Theriot, 2006 |
| Shionodiscus poro-irregulatus (Hasle & Heimdal) A.J. Alverson, S-H. Kang & E.C. Theriot, 2006 |
| Skeletonema Grev., 1865 |
| Skeletonema costatum (Grev.) Cleve, 1873 |
| Skeletonema tropicum Cleve, 1900 |
| Stephanodiscus Ehrenb., 1845 |
| Stephanodiscus astrea (Ehrenb.) Grunow, 1880 |
| Stephanodiscus dubius (Fricke) Round, 1982 |
| Stephanodiscus hantzschii Grunow, 1880 |
| Stephanodiscus niagarae Ehrenb., 1845 |
| Thalassiosira Cleve, 1873 |
| Thalassiosira aestivalis Gran, 1931 |
| Thalassiosira alleni Tanako, 1965 |
| Thalassiosira angulata (W. Greg.) Hasle, 1978 |