Opegrapha demutata

Opegrapha demutata is similar to Alyxoria ochrocheila (Opegrapha ochrocheila) but is distinguished by the white (K–), not orange (K+ purple) pruina and saxicolous habit. Found on brickwork and shaded flint; rare and very local. E. & S. England; Lincolnshire (Gibraltar Point), Suffolk, Bedfordshire, Sussex (Eridge Park).

Opegrapha demutata should certainly be transferred to Alyxoria, but more research is needed to determine whether it is phylogenetically distinct from Alyxoria ochrocheila. Alyxoria subelevata has apothecia with a broad, open, blue-grey pruinose disc, a conspicuous, non-pruinose exciple, larger ascospores and shorter conidia.