Gymnodoris sp.

Image courtesy of Ali Hermosillo McKowen
Komodos, Indonesia

Photo courtesy of David Cowdery
Bontoh Village Sangeang, Komodos, Indonesia
Gymnodoris sp. 45 (in NSSI, 2nd edition)

Wow - Yikes - another quagmire (quagmire is a Polysyllabic Anglo-Saxon Derivative for sticky, dilemma or predicament). Members of the Gymnodorididae are probably the least understood of all the dorids. Several of our colleagues have ventured into this taxonomic sticky-wicket, but none have been successful in sorting species out, as can be seen with the 61 undescribed species included in Nudibranch and Sea Slug Identification, 2nd edition.

Only 30 species have been described. As mentioned in NSSI, many of the descriptions are incomplete and it is extremely difficult to determine which species are which. We give the example that Gymnodoris bicolor and G. alba probably represent about 20 different species.

Ali's critter here is what we have designated as Gymnodoris sp. 45, awaiting description and a legitimate scientific name. This species is included in a group with other species having a large, slightly divided gill forming a nearly complete circle that is facing posteriorly. This species is uniformly bright yellow. The rhinophores are bulbous. Its internal organs are visible through the skin.

It is active nocturnally and feeds on other opisthobranchs. Known from the Philippines and Indonesia.

Dave Behrens
Sammamish, WA 98074
Feb., 2021
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Ali Hermosillo McKowen on location in the Philippines

Ali needs very little in the way of introduction to readers of this site. She has been featured in many of the Branch of the Week (BOW) presentations through the years. Diving with Ali can be infectious assuming you can keep up with her. If you didn't have an appreciation for our friends the sea slugs before diving with her, you will certainly reach quantum levels in that regard as Ali is all consuming in her quest to photograph and document their behavior! In the last few years she even acquired her Doctorate in Opistobrach Studies so her enthusiasm certainly knows no bounds. She has the material for putting together field guides for both the Milne Bay region of PNG and also Anilao in the Batangas area of the Philippines. Let's encourage her when time permits to make that happen!

As a side note Ali has posted ID's with her Flicker postings from both areas. The links can be seen in the left frame of this site. Very worth while to visit for those who are seeking to put names together with images.

What more can be said, Ali is the greatest!

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Michael Miller
San Diego, Calif
Jan., 2021
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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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