| Procerodes ulvae (Ørsted, 1843) | 1932 or earlier | | | Jekaterinhafen. |
| Uteriporus vulgaris Bergendal, 1890 | 1932 or earlier | | | under rocks, Jekaterinhafen. |
| Notentera ivanovi Joffe, Selivanova & Kornakova, 1997 | prior to 1997 | | | from the digestive tract of a polychaete Nephthis ciliata from the White Sea. |
| Baicalellia pusilla (Luther, 1962) | 1988 or earlier | | | |
| Alauretta viridirostrum Mereschkowsky, 1878 | 1878 or earlier | | | |
| Prostomum boreale Mereschkowsky, 1878 | 1878 or earlier | | | |
| Prostomum papillatum Mereschkowsky, 1878 | 1878 or earlier | | | |
| Mesostomum graffi Mereschkowsky, 1878 | 1878 or earlier | | | |