Description: A common crustose lichen of brick wall tops, standing stones and sandstone monuments, both in the country and the town. It is often overlooked, but the speckled-green to grey granular thallus pocked with blue-green soralia (spots) can easily catch the eye. The blue-green colour alone should be sufficient to attract attention. A useful test is to apply a dab of fresh bleach which will turn the thallus orange. Black discs are occasionally present.

Key Identification Features:

• Grey-green thallus with scattered blue-green soralia: a combination which is soon memorised. Discs black, slightly convex
• Spot test: dab of fresh bleach will turn it orange.

Original text submitted by Vince J. Giavarini

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

iNaturalist: Lecidella scabra at iNaturalist World Species Observations database.