Description: This easily overlooked crustose lichen is totally unique to Ireland. Currently, it is known only from a single collection from the Aran Islands. In appearance it is very similar to the watercourse species V. aquatilis, but differs in the slightly larger spherical discs (perithecia), cracked thallus and habitat which is shaded limestone not the submerged bedrock of acid streams.

Key Identification Features:

• Thin brown to black, much cracked thallus; spores 7-11 x 5.5-7ųm (slightly larger in V. aquatilis)
• Discs semi-immersed; at base of limestone wall; endemic.

Original text submitted by Vince J. Giavarini

Distribution Map from NBN: Verrucaria aranensis at National Biodiversity Network mapping facility, data for UK.

iNaturalist: Verrucaria aranensis at iNaturalist World Species Observations database.