Thecacera sp.

Photo courtesy of Jim Black
Raja Ampat at about 130 feet, Indonesia

RS System with 50 mm macro and super macro adapter

Thecacera sp., undescribed

Earlier this year while thumbing through Nudibranchs of the World (Debelius amd Kuiter), I came across many great images of branchs that were entirely new to me. One that immediately caught my attention was that of Thecacera sp. 5 at the bottom of page 41 taken by veteran world traveler and ace underwater photographer Jim Black, who should be familiar as a major contributor to the Slug Site through the years. Jim is still taking super pics with his venerable RS system although I have heard rumors that he may be going digital!

This week's subject also presented from a lateral view seems familiar but at the same time different based on the blue coloration with white crown seen at the tips of the long branchial appendages. This feature seems to set it apart from a "cousin" that was photographed close by preparing to munch on some sand dwelling bryozoans The cousin of course has been widely photographed in the Indo-Pacific and featured both on this site and also Bill Rudman's Sea Slug Forum

As it turns out our BOW star is also featured on page 373 of Neville Coleman's new nudibranch book ! This guy is getting a lot of well deserved exposure thanks to Jim's super photos!

For those of you who would like to see the cousin feeding in video flash format, try Thecacera sp. Video taken by the Webmaster at Komodos, Indonesia in October of 2007.

I am going to digress a little bit so some may want to tune out as the discussion will not impact your understanding of underwater branch photography but you may gain some insight into what seems to be a bottomless pit of taxonomic discussions as to what constitutes a "distinct" species. Earlier this week, I picked up my copy of the June issue of Scientific American to read an article on forensic imaging while on the treadmill at the gym. Well, as it turns out the article immediately following it on page 72 is the one that really caught my eye! The Title" What is a Species? " by Carl Zimmer. While putting this BOW together I was wondering whether our two Thecacera sp.'s were in fact "kissing" cousins or perhaps far more removed as in "distant" cousin? The discussion that ensued in this article is probably old hat to the "professionals" but it was certainly an eye opener to me. A few catch quotes are going be presented to wet your appetite for more! Both are from Darwin.The first" "... I look at the term "Species" as one arbitrarily given, for the sake of convenience, to a set of indiviuals closely resembling each other..". The second "...It all comes , I believe from trying to define the indefinable..." Beat a path down to the library or newstand to read the article in its entirety. Well worth your time!

Michael Miller
San Diego, Calif
Jun, 2008

Jim Black on location

Jim is retired from US Airways after 27 years as a pilot..., flying Captain on an Airbus 330 Internationally.

Diving since 1970...with over 5200 dives logged. Shoots Nikon F4s in housing and Nikonos RS.

Jim's photography has been featured in a number of books and publications including Helmut Debelius' Nudibranchs and Sea Snails of Gosliner, Behrens and Williams Coral Reef Animals of the Indo-Pacific. A photo of Jim petting a shark in "Sleeping Shark Caves" off Isla Mujeres Island, Mexico, taken by Amy Foster his significant other, recently appeared in Dave Behrens' Diving Guide to Cozumel, Cancun & The Riviera Maja.

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