Description: In oceanic woodlands with outcrops of damp, acid rock this species appears as a thick, generally smooth and minutely brown dotted, creamy-blue crust — as though soft porridge had been poured over the rock and left to set. It has a conspicuous black border. Discs (to 0.7mm) are common, brown and convex. Western Ireland mainly.

Key Identification Features:

• Thallus thick, creamy, greenish or pale blue, textured like soft porridge
• Thallus, speckled brown; discs, brown, convex; oceanic woods with outcropping rock, shallow ravines, etc.

Original text submitted by Vince J. Giavarini

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

iNaturalist: Herteliana gagei at iNaturalist World Species Observations database.