Yes, dragons are a good case in point. Another new innovation being the ability to learn human langauges whilst in the egg (Temeraire).

Non-standard dragons also go back a long way, at least as far as The Reluctant Dragon by Kenneth Grahame.

I do agree that JK Rowling's boggart was totally wrong for a boggart. She must have just liked the name and assumed that no one would know the original boggart stories so it didn't matter if she used it for her own invented creature.