Divers will tell you that the true sea lemon (nobilis) has the black spots on its back that are between its bumps (tubercles), it has both rhinophores up front and 6 branchial plumes about ¼ inch from the postieror end and both are whiter than the rest of the animal. The guy in the picture is a True Sea Lemon(nobilis). Note the black dots are not on AND in between the tubercles as in the false sea lemon (montereyensis).
Check out the feeding cirus on the barnicle on the right.
