Rhizocarpon geographicum

Map lichen

(rhizocarpon geographicum)

Map Lichen (Rhizocarpon Geographicum) on the Old Killarney/Kenmare Road, Co. Kerry, Ireland

A distinctive form of lichen that grows on rocks in areas of low pollution, usually in mountainous areas. Each lichen is a flat patch bordered by a black line of spores. These grow adjacent to each other and are usually of differing colours leading to the appearance of a map or a patchwork field.