Kate's Mystery Books by LenEdgerly Creative Commons
Great post on genre over at BookEnds today.
It looks like the best thing you can do is get it in the right ballpark and then tailor your query to the specific interest of the agents. So though my book is paranormal, it could be a paranormal romance because she has romantic relationships, or it could be paranormal mystery because the whole series is about finding out who killed the MC and her entire family.
Basically don't get too caught up in genre. Regardless of what you think your book is, the writing is what will get your foot in the door. And they can't see the writing if you never send that puppy out there.