Well it's been a kinda weird week, so why not start the next off just as weird.
Allan and Barbara Jones of Anaheim Hills, CA sent us this beautiful shot of a Chromodoris kuniei with a cone shaped abnormality up front on the mantle. Kinda forms a weird hat neatly placed between the rhinophores. You might also note that this specimen also has three rhinophores. Developmental abnormalities such as these are becoming more frequent, not necessarily in nature, but in documentation, as divers look closer and take photos of things that don't look right to them. These interesting finds are hard to explain.
Hard to say what causes the miss-formed and duplicated tissues, other than to say they are accidents occurring during the development of the larvae. A similar little extra piece of mantle is seen in Mary Jane Adam's Chromodoris tinctoria here.
Mike's Nembrotha is another example of a specimen with too many rhinophores. All three seem to have developed perfectly. Makes one wonder if the animal can smell better with the extra organ?
Some abnormalities, primarily missing tissues, are caused by accident or by attack by a predator. There are many examples on Bill Rudman's Sea Slug Forum on the Abnormalities Page .
The weirdest one I've seen to date is Mary Jane's
Chromodoris leopardus with two complete anterior ends to the mantle, sans rhinophores and mouth. It would be interesting to see if the internal anatomy of the duplicated mantle tissue, was also duplicated.
I retired 2 years ago from a position as a manufacturing operations executive and my wife Barbara, last year from a teaching position in Santa Ana .
We use Nikon N90s in Subal and Nexus housings and also Nikonos III and V. For macro we use Ike Sub 50's and wide angle, Ike 200's.
I still dive in CA with the Orange County UPS and the Sea Sabres in Fullerton CA. Most of our diving is in the south Pacific with our favorite areas in eastern Indonesia to PNG.
Send Allan mail at firstname.lastname@example.org
David W. Behrens
Pacific Coast Nudibranchs
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