Yes, they were in a mixed species aviary with Speckled Pigeons in Jungle Trails, but I had heard that they might move to the Butterfly Rainforest. The zoo no longer shows them on their website, so it's likely that they're gone. What a shame if they have.
I would say there used to be around a half a dozen species of butterflies in the Butterfly Rainforest. I have no idea what has happened to them all. It doesn't make much sense to have only one species of butterfly in a butterfly exhibit.