| Convoluta convoluta (Abildgaard, 1806) | prior to 1905 | littoral | | |
| Plagiostomum girardi (Schmidt, 1857) | 1955 or earlier | | | |
| Plagiostomum koreni Jensen, 1878 | Jul 8, 13, and 17, 1950 | tide pool | | |
| Plagiostomum vittatum (Frey & Leuckart, 1847) | Jul 8 and 21, 1950 | | | |
| Plagiostomum cinctum Meixner, 1938 | Jul 18, 1950 | 6-10 m | | at the breakwater |
| Childia groenlandica (Levinsen, 1879) | prior to 1975 | 70-80 m | clay | |
| Childia crassum (Westblad, 1942) | prior 1975 | 70-80 m | | |
| Childia submaculatum (Westblad, 1942) | prior 1975 | 70-80 m | clay | |
| Pelophila lutheri (Westblad, 1946) | prior 1975 | | sand | sandy beach. |
| Mesorhynchus terminostylis Karling, 1956 | 1956 or earlier | 70-80 m | loamy clay | |
| Provortex balticus (Schultze, 1851) | 1913 or earlier | | | |
| Provortex affinis (Jensen, 1878) | 1913 or earlier | littoral | | |
| Graffilla buccinicola Jameson, 1897 | 1913 or earlier | | | in the kidney of Buccinum undatum L. and Neptunea antiqua L. |
| Maehrenthalia agilis (Levinsen, 1879) | 1913 or earlier | | | |
| Maehrenthalia intermedia (Graff, 1882) | 1897 or earlier | | | |
| Astrotorhynchus bifidus (McIntosh, 1874) | 1897 or earlier | | | |
| Proxenetes flabellifer Jensen, 1878 | 1913 or earlier | | | beach water. |
| Promesostoma marmoratum marmoratum (Schultze, 1851) | 1913 or earlier | | | very active, in marine and brackish water. |
| Promesostoma marmoratum (Schultze, 1851) | 1913 or earlier | | | very active, in marine and brackish water. |
| Promesostoma ovoideum ovoideum Graff, 1905 | 1913 or earlier | | | |
| Promesostoma ovoideum purum Graff, 1905 | 1913 or earlier | | | |
| Promesostoma solea solea Graff, 1905 | 1913 or earlier | | | |
| Promesostoma lenticulatum (Schmidt, 1852) | 1913 or earlier | | | |
| Trigonostomum armatum (Jensen, 1878) | 1913 or earlier | 0-27 m | | found in Fucus at depths up to 27 m. |
| Acrorhynchus caledonicus (Claperede, 1861) | 1913 or earlier | 1-3 m | | in ebb tide pools, and litoral zone in large numbers. |
| Polycystis naegelii Kölliker, 1845 | 1913 or earlier | | | living among plants in the litoral zone. |
| Polycystis crocea (Fabricius, 1826) | 1913 or earlier | | | |
| Phonorhynchus helgolandicus (Metschnikow, 1865) | 1913 or earlier | | | |
| Fecampia erythrocephala Giard, 1886 | 1913 or earlier | | | |
| Plagiostomum sulphureum Graff, 1882 | 1913 or earlier | littoral | | lively swimmer. |
| Plagiostomum vittatum (Frey & Leuckart, 1847) | 1913 or earlier | | | |
| Plagiostomum koreni Jensen, 1878 | 1913 or earlier | | | |
| Plagiostomum vittatum (Frey & Leuckart, 1847) | 1897 or earlier | | | |
| Vorticeros auriculatum (Müller, 1784) | 1913 or earlier | 0-35m | | littoral up to 35 m deep in Algen and Bryozoen. |
| Pseudostomum quadrioculatum (Leuckart, 1847) | 1913 or earlier | | | |
| Pseudostomum inerme (Hallez, 1879) | 1893 or earlier | | | among algae. |
| Allostoma pallidum Beneden, 1861 | 1913 or earlier | | | |
| Allostoma austriacum (Graff, 1882) | 1913 or earlier | | | |
| Monocelis fusca Örsted, 1843 | 1913 or earlier | | | |
| Monocelis lineata (Müller, 1773) | 1913 or earlier | | | |
| Graffilla buccinicola Jameson, 1897 | 1897 or earlier | | | |
| Plagiostomum sulphureum Graff, 1882 | 1893 or earlier | | | |
| Paramesostoma helgolandicum Ax, 1959 | 1959 or earlier | | | |
| Aphanostoma diversicolor Ørsted, 1845 | 1905 or earlier | | | Irishe Sea (Port Erin auf Man) |
| Syndesmis echinorum Francois, 1886 | 1963 or earlier | | | from Echinus esculentus (Echinidae). |