Got it.
It is a species of Oxynoe and feeds on caulpera. I found it on the Sea Slug Forum.
Interestingly, i can nail down exactly where this came from. All of my live rock was aquacultured off the coast of Florida. When i got it, the rocks were covered in a variety of caulepra types. This little bugger must have been feeding on them. Interestingly, it survived the cycling of the tank okay.
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