A 340 million-year-old fossil found in a wall in Tuam, Co Galway, is being unveiled at a public exhibition in the town today.
The fossil was discovered on a rock in a stone wall in 2017.
Known as Phanerotinus Cristatus, it is a rare giant fossil snail, which has been dated to the Carboniferous Period. This refers to a time when Ireland was located close to the equator and covered by a warm tropical sea.
The Tuam fossil is one of only 15 such specimens to have been found to date, all of them originating from a band of limestone stretching between Ireland and Britain.
The find was made by Galway geological enthusiast Brendan Arrigan, while he was walking on the Ballygaddy Road in Tuam. Mr Arrigan had completed a geology course at NUI Galway and spotted the evidence of what would have been a gigantic snail with spiny flanges around the outside.
It was dated to the period in question, following analysis by experts from the Geological Survey of Ireland.
The discovery comes as a four year audit of Co Galway's geological heritage nears completion.
The fossil is going on display at the town library.
