As regards the gadid, in Cod the first anal fin should begin below the second dorsal, and here it's clearly below the first dorsal, so that's out. Whiting should have the first anal being more than half the snout-anus distance, so that's out. Saithe matches the shape reasonably well but should have a really bright and sharply-defined lateral line - it's not impossible, but I think that's out too. I think my best bet is going to be Pollack (Pollachius pollachius), although that pesky first anal fin looks a little 'blunt'; maybe it's not fully extended.
