Trapania sp. 9

Image courtesy of Webmaster
Lembeh Straits, Indonesia
Freeze Frame from CoolPix AW 130 Video

Trapania sp. 9 (in NSSI 2nd Ed.)

Fellow Sluggers, Dave is on vacation so yours truly is filling in!

First of all, I must apologize for the quality of the BOW subject above, but its the best I could do given the size of the subjects (est. 3mm) and my present camera (video) system. But its redeeming feature is that it carries on the theme of last week's BOW discourse on egg masses. I was in Lembeh for two weeks in August with Dr. Elias Amador staying at Yos Dive resort ! The water was a little on the cool side but the side benefit was the egg mass laying activity observed of many of the local sea slug inhabitants. Recording the presumed egg mass structure can greatly add to our resource knowledge of our sea slug friends! In fact, the egg mass configuration was used in the past as a tie breaker in trying to determine the relationship (if any) between two slugs with similar morphological characteristics!

Many years ago, Jim lance (my nudibranch mentor at the time) stressed again and again the importance of recording and examining egg masses to aid in the scientific distinction of species!

At this point I must digress a bit and speculate as to the utility of egg mass characteristic as a "marker" in similarity index grouping! My base knowledge of similarity indexing comes from my experience in the forensic field where agglomerative clustering was employed in the past to compare the similarity of various illicit heroin drug seizures! This of course is now ancient history and probably of no value or interest to present day researchers who now employ genetic DNA markers via phylogenetic typing to make modern day similarity assessments!

Where does egg mass characterization fit into present day work in attempting to distinguish species that exhibit similar external characteristics (color, etc) to make preliminary assessments as to presumed identity? It probably doesn't, but if Jim was alive today and looking over my shoulder, he would certainly would be chuckling!


If you're thinking mentioning Yos Dive Resort was a "plug" in the above write up, you are absolutely correct! I would highly recommend the resort for any sluggers contemplating visiting the Lembeh area. This recommendation is being made aside from any monetary considerations. E.G. I paid the same as everyone else!

There is a new kid on the block book wise! Rie Nakano has just published and updated Field Guide to Sea Slugs and Nudibranchs of Japan! This compendia will be an invaluable addition to your library despite most of the descriptions being in Japanese! More on this next week so stay tuned!

Mike Miller
San Diego, Calif
Sept., 2019
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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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