Nembrotha sp.

Image courtesy of Marcel Tanke
Lembeh, Indonesia

Nembrotha sp. taken by Marcel Tanke
Nembrotha sp. (or is it a juvenile N. mullineri?)

What's going on lately with all these spotted Nembrotha's showing up? Without analysis of the internal anatomy, the situation is really confusing.

When Terry and Angel and I prepared Indo-Pacific Nudibranchs we called this guy Nembrotha sp. 2. Since then Terry has taken a look at the internals and amazingly determined it is the juvenile color of Nembrotha mullineri. Holly smoke, the young and the old don't look anything alike. I shouldn't be surprised as we see this in Hexabranchus and other species, like Plocamophorus margaritae . In this Nembrotha, the spots change to brown with age and the blue line on the foot disappears. Hard to explain how or why the brown body color changes to white. When we look at the similarity of Marcel's critter to Nembrotha c.f. mullineri in BOW 828 you can almost see the progression.

Marcel's photo of this specimen on a large barrel sponge (not it known food) extends the geographic range to Indonesia

Dave Behrens
Sammamish, WA 98074
Aug., 2013
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Webmaster's Notes (08/17/2013) As luck would have it and as is in most matter's of science, I have received a couple of images from Jim Black that in one sense reinforce the discussion above but in another sense cause concern as to whether we are heading in the right direction! The first image taken in the Anilao, Philippines area by Jim look very much like the images taken by Wayne Lovell in BOW 828, but the second seems to display an adult form of the Marcel's specimen?? Are they the same? And if so, our progression theory of transition is at risk! So much to ponder on this quesition, it seems the more we endeavor to know about sea slugs, the more we realize that there is a lot to be learned. And I'm going to leave it at that!

Michael Miller
San Diego, Calif
Aug., 2013
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Marcel and wife Marion at Club Ocellaris, Anilao, Philippines

Marcel and Marion presently again live in their native country, the Netherlands. They started diving during the 14 years that they lived in China and Korea. Marcel has BSAC Instructor diving level. Diving took them pretty much all over Asia and many other places. Nudibranchs became their main interest after several trips to the Philippines and Indonesia. Marion is "spotter" for the nudibranchs and Marcel is taking the pictures.

Marcel is still using his "point and click" Canon Ixus 900TI Digital Camera (see )

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

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