The discovery of a well-preserved group of sea urchin fossils off the South-East coast has been hailed as one of the most “exceptional and striking fossil finds in the last century”.
The fossils were uncovered at Hook Head, Co. Wexford, by a team of scientists, led by experts from the School of Natural Sciences at University of Galway.
More than 200 complete sea urchin fossils were found preserved in exquisite detail on a limestone surface, in an area of just a square metre.
What makes this find even more special is that all the Hook Head specimens had their spines intact and apparently had died together on the seafloor almost 350 million years ago, leaving a dramatic moment now frozen in time on the rock surface off the South-East.
Sea urchins, also known as echinoids, are a group of marine animals related to starfish. The sea creatures have globular bodies covered by numerous defensive spines, which fall away and are quickly lost after the urchin dies.
Co-author of the paper and supervisor of the original project Dr John Murray, of the School of Natural Sciences at University of Galway, said it was unclear why the urchins congregated in such large quantities on the seafloor, but it can be concluded they were buried quickly, with little or no post-mortem disturbance.
Fearful the limestone layer containing the fossil urchins was in danger of being lost to coastal erosion, the scientific team mounted a rescue operation to save it. Following successful removal, the fossil-bearing slab was transferred to the National Museum of Ireland for conservation and further study.
The discovery was reported in the. One of the international scientific experts who peer-reviewed the paper said: “This is one of the most exceptional and striking fossil finds in the last century.”
Lead author in the study, palaeontologist Dr Nidia Álvarez-Armada, said she initially unearthed the fossils when surveying the geology of Hook Head peninsula as part of her thesis at the University of Galway.
“When I first noticed the echinoids on the limestone surface, I was completely astonished by both the sheer number of fossil specimens present and also their exceptional preservation,” she added.
“The significance of the find was instantly apparent, and I immediately began mapping and recording the shape, size and position of each individual urchin on the rock surface."
Speaking about the success of the project, Dr Murray credits the willingness of the team who volunteered their "time and expertise to travel to Hook Head to help salvage the fossil-bearing slab".
“We consciously chose to leave this important fossil find in the care of the National Museum of Ireland immediately - I guess it was our way of giving this piece of priceless geo-heritage back to the people of Ireland.”