Description: This rosette-forming species has a frosted, pale orange, outer fan of lobes and a darker central thallus with yellow-orange granular soredia attached to the lobe ends. It is normal for the centre of the thallus to disintegrate leaving the remainder to grow on. It can colonise mortar and tomb tops as well as nutrient-rich limestone. Discs are rare. North and south-east Ireland, rare in the west.

Key Identification Features:

• Two-tone thallus with a pale-orange growing edge and darker centre with numerous small, granular soredia
• Discs are rare; mainly in the east. C. saxicola is smaller with numerous discs.

Original text submitted by Vince J. Giavarini

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

iNaturalist: Calogaya decipiens at iNaturalist World Species Observations database.