"Hmm, I'm guessing you know about this list of FDA-approved seafood names?
http://www.accessdata.fda.gov/scripts/fdcc/?set=seafoodlist"

Yes, but I haven't used it for years. The Asian markets where I buy fish definitely have no knowledge of FDA names. A list without pictures is useless to me, and they don't list enough fish anyway.

I use Fishbase.org which lists over 33,000 fish species and has multiple photos of most of them.