Something identifiable can be picked out as itself: you can tell what it is, or who it is. A bird is identifiable if you can tell which kind it is. A person in a photo is identifiable if you can say who they are. Police and news writers use it a lot: no identifiable suspects; an identifiable brand on the bag. It does not mean “important” or “special.” It only means you can tell what or who it is. Though actually, people now stretch it toward “easy to notice” (“an identifiable style”), which is a little looser than the strict “you can name it” sense. That looser use is common, so you will meet both. The opposite feeling is “no one can tell” — too unclear to name.