Do note that the zoo’s signage labels their porcupines under the name “South African Crested Porcupine”. Yet, I was able to confirm that these in fact Cape Porcupines, via, Zootierliste.
@Austin the Sengi - "Cape" and "South African" are the same (the Cape of the name is a reference to the Cape of Good Hope in South Africa). Also, you can't "confirm" they are one or the other species simply by what it says on ZTL because it is user-edited.
I can confirm San Diego indeed holds H. africaeaustralis. I will second @Chlidonias re ZTL though, do not take any Hystrix listing at face value - there are numerous misidentifications and for cristata and africaeaustralis in particular the site is not at all accurate.
