Description: This lichen of dry, sheltered rock outcrops should be searched for along narrow stream courses, in underhangs and on bracken-covered, boulder-strewn slopes. It favours siliceous rocks and is easily recognised owing to its neat, yellow-white, powdery or fluffy (leprose) thallus, rosette-like growth form and strongly lobed margin. Individuals can be anything from a few centimetres to 20cm across. Although shaded, near vertical rocks appear to be its primary habitat. It can also occur on tree boles and on mossy surfaces. Frequent in western Ireland; scattered elsewhere.

Key Identification Features:

• The yellow-white, powdery-cottony thallus with a strongly lobed margin in the deep shade of an acid rock overhang or huge, tilted boulder should be sufficient for identification
• Lookalike species are mostly found in limestone habitats which this is not.

Original text submitted by Vince J. Giavarini

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

iNaturalist: Lepraria membranacea at iNaturalist World Species Observations database.