Mourgona sp. 2

Image courtesy of David Cowdery
Sangeang Island Indonesia, Indonesia

Kwato, China Strait, Milne Bay Province, Papua New Guinea
Photo by Jim Anderson

Mourgona sp. 2 (in NSSI 2nd Ed.)

This tiny cryptic species is quite similar to Cyerce bourbonica (Yonow, 2012). C. bourbonica can be seen on Bill Rudman's Sea Slug Forum as Cyerce Sp. 3 The main color differences are in the color of the rhinophores. A quick scan of the many hundreds of photos, called C. bourbonica, on the internet, suggests some confusion exists. Aside from the fact that these two species belong to two different genera, Mourgonia sp. 2 is translucent grey and has yellow pigment and smaller black spots on the cerata. It lacks the brown and white spots present of the rhinophores of C. bourbonica. Little if anything is known about it biology.

Mourgonia sp. 2 can also be seen on Jim Anderson's Website and to the left. Dave and Jim's photos illustrate just how cryptic this guy can be!


Kohler, E. (2018), published 14 March 2018, Cyerce bourbonica Yonow, 2012 Philippine-Sea -Slugs

Dave Behrens
Sammamish, WA 98074
July., 2019
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Dave Cowdery is a retired bio-medical Engineer and is the inventor of the Alumina/Titanium hermetic feedthrough (1970) for implantable bionics and the first to introduce a Titanium casing. This invention created the first bionic implant (pacemaker) with a service life that could be measured in years rather than months and is the basis for todays huge multi billion dollar bionic industry.

David is a Divemaster with over 5,500 dives experience and is based near Byron Bay in Australia. David is also a keen competitive road bicycle rider covering over 400 km most weeks. Photographic equipment used Nikon D800 camera with DS160 substrobes.

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Attention all you Sluggers, and you know who you are!

The NSSI 2nd edition is now available in ebook PDF and book form . The hard back version will become available Nov. 1st. Both will cost $65 (individually).

You will need to jump through a few hoops to get the electronic version as pdf distribution is protected by Adobe ID!! Please read the following to enable reading your electronic purchase!

This new 2nd Edition is updated and reorganized, including 185 new species. Among other features, the new edition includes additional photographs of species, an identification key, and an up-to-date classification reflecting the latest evolutionary relationships. The Indo-Pacific represents the largest expanse of tropical ocean in the world, stretching from the Indian Ocean coast of southern Africa and the Red Sea to the central Pacific of the Hawaiian Islands, Easter Island and the Marquesas.

This region supports the most diverse marine fauna of any place in the world for most groups of marine organisms. The nudibranchs and sea slugs are no exception to this rule; there are about 3,000 described species of these organisms in the world and at least 40% of these have been found exclusively in the Indo-Pacific tropics. This book illustrates 2,138 Indo-Pacific nudibranchs and sea slugs, including many undescribed species.

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

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