@aardvark250 When I was researching reptile and amphibian holdings in Japan using the JAZA website, I found that Maruyama had one of the largest herp collections in the country with several rare species; does that hold up based on your recent visit? How many species/exhibits were in this building?
It is one of the better reptile house in the country I would agree. There's around 40 to 50 species but there may be some more behind the scenes. May post a species list soon.