Ingaderia sorediata (Fulvophyton sorediatum) (Peterjamesia sorediata, Sclerophytomyces circumscriptus var sorediatus) Growth type crustose Chemical results: K +/- pale yellow, C-, KC-, P+ yellow, UV+ pale cream Restricted to south-west and western coasts where it occurs under sheltered underhangs and in recesses of acidic rock faces. Mosiac-forming whitish or grey thallus, either with or without white pruina and usually with a conspicuous black prothallus. The bluish-grey or white soralia are irregular and often confluent. Apothecia are unknown. Similar: Roccellographa circumscripta (Peterjamesia circumscripta). Arthonia endlicheri is C+ red

Ingaderia sorediata, Fulvophyton sorediatum
On chert. Portland, Dorset. March 2016