I tried to come up with a pack of animals fitting for a nocturnal animal pack with the criteria that they must be:
1. In line with the current game mechanics (no aviaries, aquariums, or exhibit mammals)
2. Not complete reskins
3. Must be fitting for a Nocturnal house
4. Unique from each other...
This pack adds in nocturnal animals!
1. Aye-aye OR Potto OR Slow loris OR Tarsier OR Slender loris OR Wooly lemur OR Sportive lemur
2. Margay OR Red fox OR Bat-eared fox OR Ocelot OR Honey badger
3. Platypus OR Tiger quoll
4. North island brown kiwi OR Kakapo OR Black-crowned night heron
5...
Who doesn't love nocturnal houses in zoos?
Also a great chance to teach guests (and by extension players) about light pollution.
Animals which could fit:
Aye Aye
Galago
Slow Loris
Giant Cloud Rat
Clouded Leopard
European Hedgehog
Margay
Sugar Glider
Panamanian night monkey
Indian Porcupine...