Where to hippos come from?

[KageTokage]

I read somewhere (It can be true or false) about Hippos originating from Meracydia and they made to Thavnair via trade routes.

The hippo minion is where that bit is mentioned.

Given that there's also kangaroos and koalas over there, it feels safe to assume Meracydia is a mash-up of Africa and Australia when it comes to native wildlife.