Ancient Predatory Fish with Large Fangs and Bony Scales Discovered in Australia’s Red Centre
In the remote fossil fields west of Alice Springs, Australia, a remarkable discovery has been made. A team of researchers led by Flinders University paleontologist Dr. Brian Choo has unearthed the fossil of a sleek predatory lobe-finned fish with large fangs and bony scales. This newly described species has been named Harajicadectes zhumini, paying homage to the Harajica Sandstone Member where the fossils were found and Professor Min Zhu, who has made significant contributions to the study of early vertebrates.
Harajicadectes belongs to the ancient Tetrapodomorph lineage, some of which eventually became ancestors of limbed tetrapods, including humans. What sets this fish apart is the presence of large openings on the top of its skull known as spiracular structures. These structures are believed to facilitate surface air-breathing, similar to modern-day African bichir fish. This feature is found in multiple Tetrapodomorph lineages during the Middle-Late Devonian period.
Interestingly, this air-breathing adaptation seems to have emerged during a time of decreased atmospheric oxygen. Professor John Long, a leading Australian expert on fossil fish and coauthor of the study, suggests that the ability to supplement gill respiration with aerial oxygen may have provided an adaptive advantage for these ancient fish.
The discovery of Harajicadectes was not an easy feat. Fragmentary specimens were first discovered by ANU Professor Gavin Young in 1973, and further fossils were recovered in 1991. However, it wasn’t until Flinders University’s 2016 expedition that an almost complete specimen was found, confirming that all the isolated bits and pieces collected over the years belonged to a single new type of ancient fish.
The significance of this finding extends beyond the discovery itself. It sheds light on the evolutionary context of these ancient fish and their adaptation to changing environmental conditions. The synchronized appearance of air-breathing adaptations in different lineages suggests a common response to decreased atmospheric oxygen during the mid-Devonian.
The research conducted by Dr. Choo and his team is the culmination of 50 years of exploration and study. The fossils have been transferred to the Museum and Art Galleries of the Northern Territory in Darwin, where they will be preserved and studied further.
This discovery not only adds to our understanding of ancient fish species but also highlights the rich paleontological history of Australia’s Red Centre. The rivers that once flowed across the now arid interior of Australia were home to a diverse range of bizarre animals, including Harajicadectes, a formidable predator with its large fangs and bony scales. Through meticulous research and exploration, scientists continue to unlock the secrets of our planet’s past, revealing the fascinating stories of ancient life forms that once roamed the Earth.
