| Conaperta lineata (Peebles, 1915) | 1915 or earlier | shallow waters, near shore | seaweed near shore | |
| Convoluta convoluta (Abildgaard, 1806) | prior to 1905 | littoral | | |
| Microstomum rubromaculatum Graff, 1882 | prior to 1882 | | | 2 specimens on Lomentaria kaliformis. In Naples Bay. |
| Promesostoma ovoideum (Schmidt, 1852) | prior to 1882 | | | |
| Promesostoma solea (Schmidt, 1857) | prior to 1882 | | | found at the same places as Promesostoma ovoideum. |
| Proxenetes gracilis Graff, 1882 | prior to 1882 | | | lively animal found between aquatic plants in the Bays of Triest and Neapel. |
| Convoluta schultzii Schmidt, 1852 | 1866 or earlier | | | |
| Hypotrichina tergestina Calandruccio, 1897 | 1897 or earlier | | | parasite on Nebalia. Notes that species is found in Trieste, Marsiglia, and Napoli. Repiachoff did not name the species. |
| Stenostomum sieboldi Graff, 1878 | 1913 or earlier | | | |
| Graffilla parasitica (Czerniavsky, 1880) | 1881 or earlier | | | in Tethys leporina L. |
| Trigonostomum setigerum album Graff, 1905 | 1905 or earlier | | | |
| Trigonostomum penicillatum (Schmidt, 1857) | 1913 or earlier | | | |
| Otoplana intermedia Du Plessis, 1889 | 1913 or earlier | | | Posilippo near Naples. |
| Hoploplana insignis (Lang, 1884) | 1884 or earlier | | | |
| Anoplodium graffi Monticelli1892 | 1931 | | | found in sea-cucumber Holothuria impatiens at the Zoological Station Naples. |
| Monticellina longituba Westblad, 1953 | 1931 | | | found in sea-cucumber Holothuria impatiens at the Zoological Station Naples. |
| Cestoplana rubrocincta (Grube, 1840) | 1944 or earlier | | | |
| Pseudomonocelis ophiocephala (Schmidt, 1861) | Nov 7, 1955 | | | Italian coast at the Tyrrhenin Sea: Naples (Papi, pers. comm.) |
| Stylochus neapolitanus (Delle Chiaje, 1841-1844) | 2005 or earlier | | | |