| Hofstenia atroviridis Bock, 1923 | Jun, Jul 1914 | shallow, surf zone |  | Exposed coast.  Slow acting animal found in shallows of ebbing tide, in tide pools, and at greater depth between Laminaria roots.  Found between Corallina- Bestaenden. | 
| Neostylochus fulvopunctatus Yeri & Kaburaki, 1920 | prior to 1920 | intertidal |  |  | 
| Otocelis rubropunctata (Schmidt, 1852) | prior to 2004 |  |  |  | 
| Amphiscolops sp. Steinbock, 1938 | prior to 1965 |  |  |  | 
| Convoluta sp. Sabussow, 1897 | prior to 1965 |  |  |  | 
| Paramecynostomum diversicolor (Ørsted, 1845) | prior to 2004 |  |  |  | 
| Vorticeros lobatum Tozawa, 1918 | 1918 or earlier |  |  |  | 
| Vorticeros ijima Tozawa, 1918 | 1918 or earlier |  |  |  | 
| Leptostylochus ovatus Kato, 1937 | Sep 25, 1930 |  |  | single specimen obtained from the undersurface of stone between tidemarks at Araibama. | 
| Discostylochus yatsui Kato, 1937 | May 15, 1933 |  |  | collected on the underside of stone in the tidal zone at Araibama. | 
| Cryptophallus eximius Kato, 1937 | Jul 26, 1930 |  |  | single specimen collected under the stone near the low tidemark at Bentensita. | 
| Stylochoplana clara Kato, 1937 | 1930-1936 |  |  | species is commonly found living on Zostera and Phyllospadix all year round. | 
| Paraplanocera rubrifasciata Kato, 1937 | Sep 9, 1932 | 27.4 m |  | single specimen dredged from a depth of 15 fathoms off Hutamatiya. | 
| Pseudoceros sagamianus Kato, 1937 | Apr 6, 1935 |  |  | single specimen collected at Bentensita. | 
| Prosthiostomum auratum Kato, 1937 | Aug 28, 1936 |  |  | found creeping on Phyllospadix. | 
| Prosthiostomum purum Kato, 1937 | 1932 | 27.4 m |  | six specimens collected in the autumn from a depth of 15 fathoms off Hutamatiya. | 
| Prosthiostomum yerii Kato, 1937 | Sep 7, 1932 | 27.4 m |  | one specimen from a depth of 15 fathoms off Hutamatiya. | 
| Discocelis japonica Yeri & Kaburaki, 1918 | 1937 or earlier |  |  |  | 
| Stylochoplana pusilla Bock, 1924 | 1938 |  |  | This species is a small parasitic form, found in the mantle cavity of Monodonta labio.  Also harbours in the mantle cavity of Cellana toreuma. | 
| Pseudostylochus takeshitai Yeri & Kaburaki, 1918 | 1938 or earlier |  |  |  | 
| Planocera reticulata (Stimpson, 1855) | 1932-1933 |  |  | found in abundance in this district and Misaki all the year round; multi-tenticular forms often occur. | 
| Discocelis fulva (Kato, 1944) | 1944 or earlier |  |  | Misaki; Susaki.  Common under stones between tidemarks in summer. | 
| Stylochus ijimai Yeri & Kaburaki, 1918 | 1944 or earlier |  |  | Misaki. | 
| Leptostylochus gracilis Kato, 1934 | 1944 or earlier |  |  |  | 
| Cryptocelis ijimai Bock, 1923 | 1944 or earlier |  |  |  | 
| Notoplana delicata (Yeri & Kaburaki, 1918) | 1944 or earlier |  |  |  | 
| Notoplana japonica Kato, 1937 | 1944 or earlier |  |  |  | 
| Discoplana takewakii Kato, 1935 | 1944 or earlier |  |  |  | 
| Zygantroplana clepeasta Kato, 1944 | 1938 |  |  | two specimens found on Clepeaster japonicus Döderlein by Dr. K. Takewaki in the summer of 1938. | 
| Hoploplana ornata Yeri & Kaburaki, 1918 | 1944 or earlier |  |  | Misaki. | 
| Planocera purpurea Yeri & Kaburaki, 1918 | 1944 or earlier |  |  |  | 
| Planocera profunda Kato, 1937 | 1944 or earlier | 32-36 m |  |  | 
| Planocera multitentaculata Kato, 1940 | 1944 or earlier |  |  | Usually found together with Planocera reticulata. | 
| Paraplanocera oligoglena (Schmarda, 1859) | 1944 or earlier |  |  |  | 
| Callioplana marginata Stimpson, 1857 | 1944 or earlier |  |  |  | 
| Pseudostylochus obscurus (Stimpson, 1857) | 1944 or earlier |  |  |  | 
| Pseudostylochus fulvus Yeri & Kaburaki, 1918 | 1944 or earlier |  |  |  | 
| Thysanozoon brocchii (Risso, 1818) | 1944 or earlier |  |  |  | 
| Thysanozoon vulgaris Palombi, 1939 | 1944 or earlier |  |  |  | 
| Pseudoceros flavomarginatus Laidlaw, 1902 | 1944 or earlier |  |  |  | 
| Pseudoceros reticulatus Yeri & Kaburaki, 1918 | 1944 or earlier |  |  |  | 
| Pseudoceros gratus Kato, 1937 | 1944 or earlier |  |  |  | 
| Pseudoceros sagamianus Kato, 1937 | 1944 or earlier |  |  |  | 
| Pseudoceros nipponicus Kato, 1944 | 1944 or earlier |  |  | Misaki. | 
| Cycloporus japonicus Kato, 1944 | 1944 or earlier |  |  | commonly found on compound ascidians. | 
| Chromoplana bella Bock, 1922 | 1944 or earlier |  |  |  | 
| Amyella lineata Bock, 1922 | 1944 or earlier |  |  |  | 
| Prosthiostomum rubropunctatum Yeri & Kaburaki, 1918 | 1944 or earlier |  |  |  | 
| Prosthiostomum ostreae Kato, 1937 | 1944 or earlier |  |  | found on cultivated oyster-shells. |