Furthering the Irish links.
Cyttiau 'r Gwyddelod is at llanrug and is also known as the Irishmens huts.
http://www.genuki.org.uk/big/wal/CAE/Llanrug/index.html
There is no mention of this stone or the author in Darvill and Wainwrights 2003 provisional list of rock art in Wales