A groundbreaking discovery has emerged from the Australian Museum's McGraths Flat fossil site near Gulgong, NSW. The fossilized freshwater smelt, Ferruaspis brocksi, represents the first of its kind found in Australia. This 15-million-year-old species lived in an oxbow lake during the Miocene era and offers significant insights into the ancient environments of Australia. The remarkable find enhances understanding of Australia's evolution and provides a unique glimpse into the past.
The species Ferruaspis brocksi was discovered encased in iron-rich rock, a factor that inspired its name. The fossil features preserved stomach contents, revealing a diverse diet that included small phantom midge larvae. In addition to its dietary habits, the fossilized fish had a juvenile freshwater mussel, known as a glochidium, attached to its tail. Such findings offer a rare look into the behavior and ecology of ancient aquatic life.
Researchers at the Australian Museum have described Ferruaspis brocksi as one of the most beautiful fossils uncovered at McGraths Flat. Dr. Matthew McCurry, a leading researcher at the site, expressed enthusiasm for the discovery.
"Not only does this fossil provide a unique snapshot into the environment in which it lived in the Central Tablelands, but also, because its stomach contents are so well preserved, it allows us a glimpse into the behavior of these ancient species. We now know that they fed on a range of invertebrates, but the most common prey was small phantom midge larvae," – Dr. Matthew McCurry.
In addition to its ecological significance, Ferruaspis brocksi's fossilized melanosomes enabled researchers to reconstruct its color pattern. Dr. Michael Frese elaborated on this innovative aspect of the study.
"Using a powerful microscope, we were able to see tiny color-producing structures known as melanosomes. Fossilized melanosomes have previously enabled paleontologists to reconstruct the color of feathers, but melanosomes have never been used to reconstruct the color pattern of a long extinct fish species," – Dr. Michael Frese.
The naming of Ferruaspis brocksi also holds special significance, as it honors Professor Jochen J. Brocks of Canberra, Australia. Professor Brocks expressed his delight at the unexpected honor.
"Collecting fossils at McGrath Flat is a highlight for me every year. Splitting the rust-red slabs of rock is like opening an ancient book, revealing the creatures that inhabited an Australian oxbow lake some 15 million years ago. This little fish is one of the most beautiful fossils there, and finding the first vertebrate among the abundant plant and insect fossils was a real surprise. Having F. brocksi named after me is a real joy," – Professor Jochen J. Brocks.