Thecacera sp.

Image courtesy of Jim Anderson
Bethlehem Dive Site, Anilao, Philippines
Photo by Gordon Tillen. Anilao, Philippines
Thecacera sp.(undescribed)

This year's Nudibranch festival at the Crystal Blue Resort produced all kinds of new finds. This new Thecacera was one example and a real surprise. Usually when we stubble across a new find it is very rare, but in the case of this Thecacera, it was probably the most common species is the area. At the Bethlehem dive site there was literally 1-3 specimens under every broken coconut shell on the bottom.

It definitely has the extra rhinophoral and extrabranchial processes found in Thecacera. They are shorter than in most species however. The body of this tiny guy is transparent with yellow spots. In Jim Anerson's photo you can even see white chromatophores in the tissue. It would be interesting to know whether these function like those in squid and octopus allowing the animal to change color.

Reproductive processes always add to what we know about a particular species. In that regard, we are fortunate to present an image at left by Gordon Tillen depicting reproductive behavior with the resulting egg mass.

Finds like this are what make Anilao special.

Dave Behrens
Sammamish, WA 98074
April, 2018
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An architect who retired from practice in 2011, Jim Anderson is fascinated by the incredibly colourful world that lies just a short distance from the shore around the coast of his home in Scotland. He learned to dive there and very quickly discovered the diversity and extravagance of life that the grey sea does well to disguise. Photography started as a means of recording these sights - to try in some way to let others into this wonderful new world that was opening up.

He commenced diving in 1987 and has recorded over 4000 dives, over 2200 around Scotland, mostly with a camera in hand and has developed special skills in capturing images that have been widely published in national diving publications and identification guides. He is the proprietor of the portal to his extensive nudibranch and other web sites covering his home country and the destinations he has visited in the Philippines, Indonesia, Maldives, Red Sea, Kenya, Ireland and in the Caribbean. He is a 1st Class Examiner with the Scottish Sub Aqua Club and delivers Nudibranch Identification courses on behalf of the UK Marine Conservation Society."

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WEBMASTER'S NOTES: Jim is being rather modest about the rigors of diving for sea slugs in his home waters. Although not mentioned the reader can be assured that getting geared up in the waters off Scotland is a challenge in itself! Our hats are off to you Jim!

Gordon on location at Anilao

Gordon Tillen is a retired American businessman living in the Philippines since 2008. He has logged over 3000 dives across the Coral Triangle and the Caribbean. His current equipment is a Canon 5D MKIII with YS-D1 strobes and Sea & Sea housing. Currently resides in Sibulan, Negros Oriental, PH.

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

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