Help with ID : Good, bad or just definitely ugly!
 

Any ideas on this little critter. I took it out and threw it in a cup of sw just in case it was a good guy. Funny thing is when I got close and finally snagged him with a net the little guy (aprox .7cm) puffed up round with spikes that reminded me of a puffer fish!

Thanks for the view and thanks for the help.

http://i48.tinypic.com/rjqyo8.jpg

Another shot in the cup of the little guy.

(perhaps might be a Berghia Nudibranch?)

http://i45.tinypic.com/nn4nme.jpg

Looks like a nudi but hard to say what kind.

http://i49.tinypic.com/35m1pcm.png

Here is a short 4 second vid clip of the critter chugging along.

http://s1276.beta.photobucket.com/us...e50c7.mp4.html

Definitely a nudi. I can't say what species though. From the look of the two "bubble tip tentacle" things up by its head makes me guess that it either go after BTA or mojano anemones... most likely mojano. Hopefully that might help you narrow your search.

nudi
 

definitely not berghia

Does this guy look similar to the above pics? The more I read about this critter things seem to fit.

Aeolidiella alba