An article published in the “Journal of Vertebrate Paleontology” reports the identification of coelacanth fossils that were previously attributed to very different animals, such as reptiles. A team of researchers led by Jacob Quinn of the British University of Bristol subjected a series of fossils to examinations such as X-rays and CT scans. The conclusion is that many fossils previously attributed to the reptile species Pachystropheus rhaeticus actually belong to coelacanths.

Some fossils have now been attributed to the family Latimeriidae, which includes the extant species, many of them have been assigned to the family Mawsoniidae, while others have an undetermined precise attribution. All of these fossils may include previously unknown coelacanth species. These fish are considered living fossils because they were thought to be extinct, but living species were discovered in the last century.

The image (Courtesy Jacob Quinn et al. 2025) shows some fossil bones of coelacanths from the Mawsoniidae and Latimeriidae families.

Jacob Quinn was studying for his master’s degree in paleobiology at Bristol when he began examining fossils from various museum collections. In some cases, they were attributed to a species during the late 19th century. Some of these fossils are on public display, while others usually lie in storage.

Many fossils were attributed to Pachystropheus rhaeticus, a marine reptile that lived in the Rhaetian, the last age of the Triassic period. This species has some characteristics very similar to those of coelacanths, which likely misled scholars who had limited means to study fossils 150 years ago. Jacob Quinn now has much more advanced knowledge and technologies, such as X-rays and CT scans, which allow examinations that paleontologists could only dream of just a few decades ago.

Already in early 2024, an article also published in the “Journal of Vertebrate Paleontology” reported the results of examinations conducted on various fossils. Jacob Quinn and colleagues offered clarifications connected to the examination of fossils attributed to Pachystropheus rhaeticus: this reptile was previously considered similar to crocodiles, but that study placed it in the group of thalattosaurs (Thalattosauria). The study included a new attribution to coelacanths of a part of the fossils they studied. In this case, the coelacanths were from the family Mawsoniidae.

Jacob Quinn’s studies continued with some of his colleagues and other researchers, resulting in this study on the coelacanths that lived in the Rhaetian in the area of ​​present-day Great Britain. Many bones are isolated, which prevented precise attribution, so much so that at times, even the family remained uncertain. However, morphological variability was noted that may indicate that some fossils belong to previously unknown coelacanth species.

The history of coelacanths is extremely long, as fish similar to today’s species date back to the early Devonian period, about 410 million years ago. The studies led by Jacob Quinn cover a limited area and a limited time period, yet the results are enriching our knowledge of what are considered living fossils. These studies prove once again how much modern technology can help paleontologists.