December 13, 2007
From: Alexei Chernyshev
Okenia distincta Baba, 1941 is a little known species described from Japan. It is not uncommon in Peter the Great Bay (Japan Sea). This species lives and feeds on bryozoans from the genus Amathia.
Locality: Peter the Great Bay, intertidal, Russia, Pacific Ocean, Japan Sea, 1 October 2007, Intertidal. Length: 3-4 mm. Photographer: A.V. Chernyshev
email@example.comChernyshev, A.V., 2007 (Dec 13) Okenia distincta from eastern Russia. [Message in] Sea Slug Forum. Australian Museum, Sydney. Available from http://www.seaslugforum.net/find/21293
Thanks very much for these photos. This has been to me a mysteru species which I have knon only from Baba's short description of a single specimen from northern Japan. In general shape and anatomy it seems to have similarities to both Okenia zoobotryon and O. mija but the rhnophores in O. distincta seem to have simple lamellae rather then the cup-shaped structures in the other two species. Baba does not describe the lamellae and they are difficult to see in your photos so I would be grateful if you could confirm this difference.
You cite the description as Baba, 1941 but the publication I have is dated 1940. Have you some evidence or reference to show the publication was not published until 1941?
Baba, K. (1940) Some additions to the nudibranch fauna of the northern part of Japan. Bulletin of the Biogeographical Society of Japan, 10 (6): 103-111.