In Japan there is iZoo which has kept and bred rare species which are not found anywhere else in Japan such as earles monitors and fiji banded iguanas. This place is not Jaza accredited if you believe that accreditation makes one place better than another.This video can give an idea about the place.
Also among all the zoos I have been in Japan Tennoji and Ueno had the best diversity of species and cage aesthetics.
Also among all the zoos I have been in Japan Tennoji and Ueno had the best diversity of species and cage aesthetics.