Ancula gibbosa

Image courtesy of Tracy Clark
Photo taken at Rosario Beach on Fidalgo Island, Washington
Size about 10 mm

Ancula gibbosa (Risso, 1818)

I would be interested in seeing protein sequencing results from the three color variations of this species. To this day I find it hard to believe that the yellow stripped variation is the same species as the variation shown here.

Tracy's white spotted specimen here matches the original description of A. gibbosa , but differs tremendously from the yellow striped variation (All links courtesy of Bill Rudman's Sea Slug Forum), previously referred to as Ancula pacifica MacFarland 1905. How can these be the same species? There is a great deal of discussion on Rudman's Forum, several submissions indicating that there are differences.

Would one of you energetic young students take this on - please? I know we can get you specimens.

Dave Behrens
Sammamish, WA 98074
Oct., 2017
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Tracy Clark

Tracy Clark was certified in 1986, a month after being certified he rented a underwatercamera in Hawaii and was hooked. Tracy worked as a Public Works Lead Worker in the San Diego area until retirement a few years back . He now dives mostly in the Seattle areas, plus a few trips to Hawaii. At the time Tracy lived in San Diego, he placed in the PCUPC photo contest, and also the San Diego Unions Nature and Eye photo contest. He has had photos published in the Pacific Diver magazine, Espacio Profundo, and also Helmut Debelius's Nudibranchs of the World. Tracy was San Diego Underwater Photographic Society (SDUPS) Photographer of the Year in 1999 and and again in 2008!

Tracy and his wife Debbie now reside in the N/W area of Washington State. But as you can see the relocation has not diminished Tracy's desire to record the underwater wonders of Mother Nature!

Tracy as you all know has been a prolific contributor to the Slug Site through the years! I really can't say enough about Tracy! Tracy's images may yet be the causation factor for the Webmaster to go back from video to still photography!

Tracy's underwater photography equipment includes a Nikon D-200, Sea & Sea housing, 60mm lens and 1.4 teleconverter and two YS-90 strobes.

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

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