Pertusariaceae Pertusaria coccodes Growth type crustose Chemical results: K+ yellow turning red, C-, KC-, P+ orange, UV- Occurs on well-lit, nutrient-rich bark of deciduous trees, occasional on siliceous rocks. Most frequent in S and SE England Greyish thallus often with pale brown or whitish prothallus. Thallus +/- covered by conspicuous coarse, smooth, globose or ovoid-elongate isidia, often brown-tipped. Apothecia very rare, punctiform discs in smooth warts. Sometimes host to Cyphelium sessile Similar: Ochrolechia subviridis is K-, C+ orange > red

Pertusaria coccodes
On Oak. Holton Lee and Pamphill Green, Dorset. December 2012 and 2015