- Valve is organized around a point (radial symmetry)
- Lack significant motility
- Oogamous sexual reproduction
Note: The specimen(s) pictured to the right are not from Antarctica, excepting Naviculoid example.
| Taxon Name | Basionym | synonyms | ID |
|---|---|---|---|
| Aulacoseira distans | Melosira distans | 114 | |
| Cavernosa kapitiana | 118 | ||
| Cyclotella meneghiniana | Cyclotella kützingiana | 126 | |
| Melosira aff. guillauminii | 181 | ||
| Melosira charcotii | Melosira charcotii | 86 | |
| Melosira dickiei | 179 | ||
| Melosira echinata | 180 | ||
| Orthoseira biportulata | 293 | ||
| Orthoseira roeseana | Melosira roeseana, M. roeseana var. epidendron, M. roeseana var. spiralis | 215 |
