Interesting! I keep imagining how enormous were the collection of zoos such as Rio and São Paulo in the 70's and 80's. Of course, animal welfare wasn't a reality at the time, and almost all the exhibits were awful, but everyday we discover more about new species that were kept at these zoos in the past.There has been at least one single lar gibbon individual kept in Rio. I was looking for some data about the Asian black bears kept at the zoo and I ended up finding a newspaper on a website called Docpro, which said that in 1970, the zoo had bought a female lar gibbon, a female Asian black bear and a king vulture from São Paulo.