Nudibranch

I am a great admirer of nudibranchs, having worked with them for a little while as a graduate student, but this is the first one that has appeared on this blog. Does anyone know the species?

The photographer writes; It's a nudibranch with a nice purple sea urchin in the background.

I don't know what sort, but I saw two of them yesterday at Port Noarlunga (Australia). This one was about 120mm long. It was in about 2m of water at low tide on the limestone reef.

[much larger image]

Image: Stephen Kittel, stephenk at internode dot on dot net.

As long as you send images to me (and I hope it will be for forever), I shall continue to share them with my readership. My purpose for posting these images is to remind all of us of the grandeur of the natural world and that there is a world out there that is populated by millions of unique species. We are a part of this world whether we like it or not: we have a choice to either preserve these species or to destroy them in search of short-term monetary gains. But if we decide to destroy these other life forms, the least we can do is to know what we are destroying by learning that they exist. If you have a high-resolution digitized nature image (I prefer JPG format) that you'd like to share with your fellow readers, feel free to email it to me, along with information about the image and how you'd like it to be credited.

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GrrlScientist (and others)
Since sending the image I have found Bill Rudman/Australian Museum's "Sea Slug Forum" and the animal in the photo I think is almost certainly Ceratosoma Brevicaudatum.
The web page that Chris referred to shows the creature (top row, second from left). Nelson Bay is on the east coast and so seems to have the lighter coloured creatures.

C. brevicaudatum seems to be quite common across the whole southern coast of the Australian continent.

It seems to me to vary in colour from lighter orange/pink/lilac (almost white) in the east, like the Nelson Bay ones, to a stunning almost rust red in the west.

StephenK