A 435-million-year-old fossil starfish discovered in Connemara by an Irish geologist has been confirmed as a new species and the oldest of its type in Ireland. The thumbnail-sized ophiuroid, or brittlestar, has also been named after its finder, Dr Eamon Doyle, in a rare honour for an Irish scientist.
The newly analysed brittlestar, a type of marine animal closely related to the starfish, dates from the Silurian period, when the first true fish and land plants appeared. It has been given the Latin name Crepidosoma doyleii by international specialists in the latest issue of the Irish Journal of Earth Sciences, published by the Royal Irish Academy.
He told RTÉ that he had been looking for fossils between Maam Cross and Leenane when he found a thin layer of them on the side of a hill. “I had an idea it was roughly 400 million years old, but starfish are very rare,” he said. “I forwarded it on and it was stored in the Natural History Museum, but these international researchers specialise in the evolution of communities and decided to examine it further.”
Brittlestars first evolved about 500 million years ago and have survived relatively unchanged to the present day, but the marine environment where Crepidosoma doyleii lived disappeared 400 million years ago.
Prof David Harper, a palaeontologist at Durham University, who wrote co-author of the study with Daniel B Blake, a professor of paleobiology, and Prof Stephen K Donovan of the Naturalis Biodiversity Centre, in the Netherlands, said the remote areas of the west of Ireland continued to yield some “exceptional fossils” that contributed significantly to the understanding of the history of life.
“These unique specimens of fossil starfish from the Silurian rocks of Connemara are a key piece of evidence in the hunt for past life in the ocean that covered Ireland, some 435 million years ago,” he said. “ We owe a great deal to the painstaking efforts of Dr Eamon Doyle, who combed these distant mountains for fossils during his PhD studies at University College Galway.”
Dr Sarah Gatley of the Geological Survey of Ireland said Dr Doyle’s find in the “aspiring geopark” area of Joyce Country, in the Maam Valley, “highlights the need to protect our geological heritage and underlines why the GSI support the three Unesco geoparks as well as the aspiring geoparks in Ireland.”