15-Million-Year-Old Fossil Fish Unveils Ancient Australian Ecosystem

Exceptionally preserved in iron-rich goethite, Ferruaspis brocksi provides rare insights into Miocene-era biodiversity and evolutionary history.

The fossil, discovered at McGraths Flat in central New South Wales, is the first freshwater fish of the Osmeriformes group found in Australia.
Preserved soft tissues, stomach contents, and color patterns reveal the fish fed on midge larvae, insects, and small bivalves while displaying countershading and lateral stripes.
The fossil was encased in iron-rich goethite, a mineral not previously known to preserve such intricate biological details.
McGraths Flat is now recognized as a 'Lagerstätte,' a rare site of exceptional fossil preservation, offering a window into Australia's Miocene-era temperate rainforest ecosystem.
The discovery advances understanding of the evolution of Australian freshwater fish, which are relatively low in diversity compared to global counterparts.