Melanochlamys diomedea? from Sth Korea

Dear Koh,
This is quite interesting. I am pretty sure this is a species of Melanochlamys. If it were Philinopsis then there would be a distinct pointed median 'crest' on the posterior border of the head shield. I would also expect the  the posterior funnel at the posterior end of the body to be large and more flared.

Sang Yul Shin's photos look very like Baba's drawing of Melanochlamys ezoensis from northern Japan. In recent messages [#13670, #13694] we have examples of a black form of Melanochlamys from the north-west part of Sea of Japan, which Russian workers consider merges into a less pigmented from like yours, which they consider is Melanochlamys diomedea.

I suspect your animal is a mottled form of Melanochlamys diomedea. If so, this find extends it distribution a long way down the north western Pacific. If anyone has photos of  Nth American examples of M diomedea to share with us, I would be very grateful.

Best wishes,
Bill Rudman