explanation.

Well, I'm going to explain, Northern Bat Ponies and Southern Bat Ponies.

Northern:
they live in the south.
they live in the badlands.
their colours are darker :

Southern:
Live up north
they haven't located them yet (tsj, what a waste)
They are lighter:

Thhay are actually prettyuch the same in food, personality and ruler. They have a gouverneur but their real ruler is Princess Luna.
They were banished after they tried to take over Celestia and Luna and are forbidden to come back. It's just waiting till we see whwhat Sweet Tune will get