Elseya is a genus that contains 9 (10? See Elseya (Pelocomastes) uberrima) species that are split into 3 Subgenera based on distribution. They are native to Australia and New Guinea (the island, not just the country).
The Subgenera in Elseya are:
Elseya (Elseya)
Elseya (Hanwarachelys)
Elseya (Pelocomastes)