New fossil sharks discovered in the Burren National Park and Donegal
Recent discoveries of teeth and a fin spine of 330-million-year-old fossil sharks by Phoebe Larkin and Emma Glanville of the National Parks and Wildlife Service, Burren National Park and local guide Cormac McGinley of Cormac’s Coast, provide the first records of strange ancient fossil sharks from the Burren, County Clare and Donegal, respectively.
The specimens were identified by a team of paleontologists including Dr. Eamon Doyle of the Burren and Cliffs of Moher UNESCO Global Geopark and his colleagues Dr. Wayne Itano of Museum of Natural History, University of Colorado, USA and Dr. Aodhán Ó Gogáin of the National Museum of Ireland, Dublin and their work has recently been published in the Irish Journal of Earth Sciences.
The Burren teeth have been identified as Psephodus magnus, a type of shark that had flat robust dental plates for crushing prey such as shellfish, rather than the typical pointed or bladed teeth we usually associate with sharks. The teeth are 30mm long and 20mm wide and would have been part of a dental pavement of multiple interlocking plates of varying sizes in the mouth of the shark. There are few modern relatives of these fish, but they are distantly related to the modern deep sea ratfish.
The fin spine from Donegal belonged to Oracanthus milleri an example of an extinct lineage of shark-like fossils known as acanthodians or spiny sharks from which all sharks evolved over 400 million years ago, there are no modern examples as they went extinct 250 million years ago, but similar fin spines are seen at the leading edge of the dorsal (back) fins of some modern sharks, such as the spiny dogfish. The fin spine is 30mm long but is incomplete. It is covered in small but robust ridged denticles that would have added an additional layer of protection to the fin spine.
The specimens added to ongoing active research into other Carboniferous fossil fish by lead author Dr. Doyle who said “It was exciting to be notified of these discoveries, as they are the first ever records of any kind of fossil fish from these locations. In addition, it is important to note that they were not found by trained palaeontologists but by people who keep an eye out for interesting things in the rocks where they work, a good example of citizen science.”
Dr. Itano added “despite having worked on these types of fossil sharks for many years there is still a huge amount that is unknown about them, so every new find is significant, these Irish examples add to the evolving global story of ancient fossil sharks.”
Dr. Ó’Gogáin said” It was important to record these finds scientifically in a peer-reviewed journal that will be a permanent record available to other palaeontologists and the general public for generations to come. Further research is ongoing and we hope to add to these finds in the coming years.”
Phoebe Larkin of the NPWS commented of “while the primary focus of the NPWS is on modern-day biodiversity it is important to note that the Burren contains a significant record of ancient biodiversity as well and we are delighted to have contributed this new material”.
The publication is available as an open access preprint: Doyle, E., Itano, W. and Ó Gogáin, A. 2026 New Records of Carboniferous Fish Teeth and Spine from Ireland. Irish Journal of Earth Sciences 45 (2027), 7-18. https://doi.org/10.1353/ijes.0.a987808