Quote Originally Posted by PyriteFool View Post
I could be wrong, but I feel like sub-genre is something for the publisher to determine.
Here's Liz's Patented Reminder that the above is true except when it's not, and you really want to know your sub-genre before you get to a publisher, because even though publishers rarely get it wrong, you're going to need to push back hard if they do.

To the OP: I don't think fantasy is as sensitive to subgenre as SF, but you should probably do your due diligence and go digging for similar stuff anyway.