Two species of freshwater mussels are currently placed in the genus Haasodonta, and one of them is H. fannyae. The interesting thing about Haasodonta is that we aren't sure what family it belongs to. Richard Johnson originally described fannyae as a Hyridella, which belongs to the family Hyriidae. But Don McMichael, who revised the Australasian freshwater mussels and had seen his share of hyriids, thought fannyae was more like a unionid, and he made up the genus Haasodonta for it. For the time being, since we haven't seen (or even heard of) soft parts for this animal, we will just have to go along with McMichael that Haasodonta belongs in the Unionidae.
If Haasodonta is a unionid genus, that would be interesting. It would be the only genus of the Unionidae to cross Wallace's Line. There are a bunch of mussels on the rest of the Indonesian archipelago, but no other member of the Unionidae makes it as far out as New Guinea. And, there are other freshwater mussels on New Guinea, but they are all hyriids similar to those found in nearby Australia.
