Diprotodon, from Ancient Greek δί- (dí-), meaning "two", πρῶτος (prôtos), meaning "first", and ὀδούς (odoús), meaning "tooth", is an extinct genus of diprotodontid marsupial from the Pleistocene of Australia containing one species, D. optatum. The earliest finds date to 1.77 million to 780,000 years ago, but most specimens are dated to after 110,000 years ago. Its remains were first unearthed in 1830, in Wellington Caves, New South Wales, and contemporary paleontologists guessed they belonged to rhinos, elephants, hippos or dugongs.