Two sites are associated with the area, the species found at these are described as the
Alcoota Local Fauna and
late Miocene Ongeva Local Fauna. The fossil deposit consists of a series of bone-bearing lenses on a single horizon. The individual lenses are about 1 m across and extend for 170 m. Bones and teeth are so abundant and often tightly packed, excavating one fossil without breaking the one below it can be difficult. The fossils indicate the existence of a complex community of
marsupials,
birds, and
crocodiles, including the greatest variety of species of
Diprotodontidae that has ever been described. The species found include one of the largest birds that ever lived, Stirton's thunderbird (
Dromornis stirtoni), the giant birds
Ilbandornis lawsoni and
Ilbandornis woodburnei, the wolf-sized powerful thylacine (
Thylacinus potens), and the large leopard-sized Alcoota marsupial lion (
Wakaleo alcootaensis). Also found at Alcoota are fossils of herds of the wombat-like diprotodontoids
Kolopsis torus and
Plaisiodon centralis, the trunked
Palorchestes painei,
Pyramios alcootense and other
kangaroos, crocodiles,
bandicoots,
possums, and small birds. ==Heritage listing==