Oxneriaria

Oxneriaria is a genus of lichen-forming fungi in the family Megasporaceae. It has nine species, all of which are saxicolous (rock-dwelling), crustose lichens. Oxneriaria is morphologically similar to Aspicilia, but differs from this genus in its mostly radiating thallus with either a wrinkled or lobate zone around the margins, in its generally smaller ascospores, and in the presence of the lichen product substictic acid. Species in the genus have a polar and arctic–alpine distribution....read more on Wikipedia.