Gymnodoris sp. 21

Image courtesy of Gordon Tillen
Dauin, Negros Oriental, Philippines
Copyright 2010 Gordon Tillen

Gymnodoris sp. 21 Undescribed )

Gordon has captured a super photo of the undescribed Gymnodoris we refer to as sp. 21 in Indo-Pacific Nudibranchs and Sea Slugs. The longitudinal ridges on the notum are identical, but his specimen is slightly lighter in color than Anne Clear's presented in our book. Like all gymnodorid's this species likely feeds on other opisthobranchs. Aside from that, nothing is known about its biology. Gordon's documentation here, adds the Philippines to its geographic range. The hitch-hiker is an interesting observation. The commensal shrimp, Periclimenes imperator can be seen symbiotically hanging out with numerous species of dorid nudibranch and sea cucumbers. See pages 158 & 165 in Nudibranch Behavior. The shrimp is thought to keep the hosts free of parasites and debris, while picking a bite of food up here and there as the slug crawls around. Pretty smart!

Dave Behrens
Gig Harbor, Washington
Mar., 2010

Gordon Tillen

I have been diving since 1964. Started in the lakes of Northern Wisconsin. I purchased my first small camera in 2006 on a trip to Fiji and took my first pictures of nudibranchs. I have been on fire with underwater photography ever since. My interest in nudibranchs has grown exponentially as well. Currently I'm retired and living and diving daily in Dauin, Philippines. My Camera system consists is comprised as follows; Nikon D300, Sea & Sea MDX300 housing, 2 Sea & Sea YS-Pro250 strobes, Nikon 105 mm macro lens.

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

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