Crescent map lichen

Crescent map lichen

Observation - Crescent map lichen - UK and Ireland. Description: Found this on a wall of a old clearance house.Thought it might be Rhizocarpon geographicum but the colour and appearance does seem to match the image on http://www.britishlichens.co.uk/species/Rhizocarpon%20lecanorinum%20small.jpg

Found this on a wall of a old clearance house.Thought it might be Rhizocarpon geographicum but the colour and appearance does seem to match the image on http://www.britishlichens.co.uk/species/Rhizocarpon%20lecanorinum%20small.jpg