Tritonia diomedea

Photo courtesy of Kenneth Kopp
Veteran's Park, Redondo Beach
Mar., 2008

Tritonia diomedea , Berg, 1894

With the local shore diving conditions in SoCal being so poor lately, we were looking forward to returning to our local night dive spot, Veterans Park in Redondo Beach, CA. Claudette Dorsey (professional Nudi Spotter) and I dive there a couple of nights a week. We've done hundreds of dives there over the last few years. On this night we took another buddy with us, Ken Liu .

After a wonderful long dive, on the way back up the canyon at the 50 foot line we came up on these huge clusters of Nudi eggs. We thought they were the Dendronotus iris eggs - they were so big. As I'm looking around for a D. iris , Claudette points out a Pleurobranchaea californica . A cool find, as they're not commonly seen on our dives at Vet's. I turn away to make a slow turn so I can get a nice up-canyon shot of it. I look over at where Claudette is pointing and she's now pointing at something else.

She's done the Nudi Bait-and-Switch when my back was turned and now had her light on a huge Pink Nudi. This thing is 3 times the size of the Pleuro

I take some shots, we move on, and we see more eggs. We look around and see ANOTHER one. We're just looking at each other - there is nothing this big at Vets park. We noticed it was the same color as the giant pink Sea Pens we have at Vets. After snapping lots of pictures, we concluded the dive.

We get out of the water, dress and rush home and, of course, grab the 3rd edition. It took a few moments to find the big guy - it looks like a Tritonia diomedea . We've never seen this one before. Reading on, we were not at all surprised to learn that it in fact eats Sea Pens - as we found both of these in an area where Sea Pens are all around.

I've attached a picture of his comical face (above), a full side shot and a shot of the eggs that got us looking for something out of the ordinary.

This is the thing I love most about diving: You can dive the same site again and again, and you never know what you'll see there.

Great friends, new critters, a lovely dive. It gets no better than that!

Kenneth Kopp
Apr., 2008

Photo cartoon courtesy of Jan Kocian

Great sleuthing job as usual for Ken Claudia, and Ken! Although the evidence for the egg mass being that of T. diomedea was circumstantial at this point, a thought lingered in my mind that I had seen a image of T. diomedea issuing egg mass, prima facie evidence of their relationship. Fortunately, Tracy Clark came to the rescue during a conversation at our clubs (SDUPS) 39th film festival last night (04/05/08). Yup, he had the image and mentioned that it might have appeared in a prior BOW. Now this was embarassing! Sure enough he was right! I had been looking for the image in all the wrong locations (other websites) and here it was residing on my site. I'm sure if you compare the egg mass in Tracy's image you will come to the same conclusion that I did, that Ken and crew were right on track with their assumption that the egg mass was that of T. diomedea . Tracy was also able to find an image of T. diomedea actually issuing the egg mass in question. Well, what more evidence does one need?

I first saw a pair of T. diomedea buried in sand at the Coast Guard Jetty at Monterey many years ago. I saw it again this past summer up in Nanamio, BC out on the sand during the daytime. The animal was quite large perhaps in the range of 4 inches. It wasn't doing much of anything but I took video of it anyway (need flash player).

As many of you probably know, this branch has been the focus of a great deal of research study. As a primer you may want to revisit an earlier BOW where this was discussed.

All in all, a great week for branching! Quoting Ken, does it get any better??

Michael Miller
San Diego, California
April 08

Kenneth Kopp

Diving since 1999. Currently doing about 260 local dives a year. Favorite Nudibranch dive is Marine Land, Palos Verdes, CA. We routinely see 12 - 14 species on a single dive there.

Got my first camera in 1974. Been shooting digital exclusively since 1998. Been shooting underwater about 3 years (mostly P&S Olympus and Sony.) Moved to the current DSLR (Nikon D200 / Ikelite rig) about 9 months ago.

Writer and Marketing executive by profession. When I'm dry, I'm usually fly fishing or pounding and shaking things as a working drummer & percussionist.

Married, no kids. We have three house Rabbits. Yeah - its weird for me, too.

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