Tritonia sp. 11

Image courtesy of Jim Black
Lembeh Strait, Indonesia

Image courtesy of Jim Black

Identifying tritonid's from photographs is not one of my favorite pastimes. They have so much variation and there are so many similar species. Half the time the photo does not clearly show the necessary anatomical features for identification. This is species proves my point.

We are calling it Tritonia sp. 11 from Nudibranch and Sea Slug Identification , but might it be Tritonia sp. 9? Even better - could sp. 9 and sp. 11 be color variations of each other? Wish I knew for sure.

Both species have reticulating patches of color on the notum. Both have branched lateral processes, which are outlined in white. It is hard to discern how many velar appendages there are. From our description, Tritonia sp. 11 has tubercles on the dorsum, which are not mentioned in the description of Tritonia sp. 9 so we must "assume" it is smooth. Could this be one of those cases where assuming makes an "ass" of "u" and "me"? Hummmm.

So, if a tuberculate dorsum is the key difference, which Jim's specimen has, we must go with Tritonia sp. 11.

Nice find Jim!

Dave Behrens
Sammamish, WA 98074
July, 2017
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Jim on location at Anilao, Philippines, May 2013

Jim Black Retired from US Airways, and now after a merger, American Airlines with 37 years service as a pilot. Jim retired as Captain flying an A330 Airbus Internationally. Diving since 1970, with close to 8000 dives now. Currently shooting a NIkon D800E in a Subal Housing with Ikelite strobes.. Jim uses a Macro Mate, and a Nauticam SMC and its Multiplier for super macro work.

Jim's photography has been featured in a number of books and publications including Helmut Debelius' Nudibranchs and Sea Snails of Gosliner, Behrens and Williams Coral Reef Animals of the Indo-Pacific. A photo of Jim petting a shark in "Sleeping Shark Caves" off Isla Mujeres Island, Mexico, taken by Amy Foster his significant other, recently appeared in Dave Behrens' Diving Guide to Cozumel, Cancun & The Riviera Maja.

Jim has also been a major contributor to (1) the New Indo-Pacific Nudibranch and Sea Slug Identification book by Gosliner, Valdez, Behrens (NSSI),(2) Tropical Pacific Reef Creature Identification by Humann & DeLoach,(3) Nudibranchs Encyclopedia by Neville Coleman,(4) Reef Fishes of the East Indies by Gerald Allen and Mark Erdmann, And many other publications.

Jim has been a solid supporter of the Slug Site since day one. His countless contributions put him near the top of the list of photographers who have greatly expanded our knowledge of sea slugs. There are a lot of kids in the formative stage of their education who are getting their first introduction to our sea slug friends via the great photographs Jim and other contributors have made to the site. My hat is off to Jim for making this presentation possible!

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From left to right, Terry Gosliner, Angel Valdes, Dave Behrens La Jolla, Calif.

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