The four dungeon dungeons have fish unique to them swimming around
The ones I have found Kembaalung has an ice fish named Kid Carp (Looks like a mooshu sheep!) a rank 2 ice fish. And a Rank 1 Balance fish that is appropriately named Yakoi :D (A Yak looking Koi fish)
Upper Zigazag has only 1 new fish but it's a very amazing looking Pharoahmari (A squid pharoah!) Oh and the rare Krokotopian Eel can be seen here O.O
What fish have you seen lurking the waters near these 4 mysterious dungeons?