Scientists from China and Australia have made a groundbreaking discovery, uncovering fossils of the mysterious ancient fish Palaeospondylus outside Scotland for the first time.
The team, led by Lu Jing from the Institute of Vertebrate Paleontology and Paleoanthropology (IVPP) of the Chinese Academy of Sciences, found these fossils in western Queensland, Australia. Dating back approximately 400 million years, this discovery pushes back the known existence of Palaeospondylus by about 10 million years.
Using high-resolution CT scanning and 3D reconstruction techniques, the researchers successfully restored the neurocranial structures of this tiny, eel-like fish, which measures just a few centimeters. These advanced imaging methods allowed them to reveal three-dimensional brain structures and mineralized tissues, providing critical evidence for resolving the evolutionary placement of this enigmatic creature.
“Our findings suggest that Palaeospondylus likely belongs to the cartilaginous fish lineage rather than the tetrapod stem group as previously thought,” said Lu Jing. This challenges long-held theories and brings new understanding to early vertebrate evolution.
The study was published as a cover article in the academic journal National Science Review and was highlighted in an accompanying commentary, which praised the team’s progress in interpreting the anatomy of Palaeospondylus and disproving previous hypotheses about its relationships.
The fossils were discovered in strata believed to be from the Early Devonian Emsian epoch, alongside other ancient fish like jawless fish, armored placoderms, early sharks, and diverse bony fish. Over 1,000 specimens of Palaeospondylus have been found since it was first documented in 1890, but its phylogenetic position remained unresolved for over a century, earning it the reputation as “one of the most mysterious early vertebrates.”
In addition to their findings, the team developed a new cross-platform volumetric data reconstruction method. This innovation enables efficient restoration and cross-verification of paleontological data, enhancing the processing and visualization of CT scans and paving the way for deeper morphological analysis in future research.
“This technique is expected to play a transformative role in future research,” Lu added, expressing optimism about the potential for further discoveries in the field of paleontology.
