Roccellaceae Lecanactis abietina Growth type crustose Chemical results: Thallus K-, C-, KC-, UV+ yellow or glaucous grey. Pruina K-, C+ red Can be frequent on dry, shaded, acid-barked trees in mature woodland. White or greyish thallus with abundant scattered pycnidia, the tips white-pruinose. Often infertile, when present apothecia are brown and usually very thickly grey-green pruinose, the spores 3-septate. Similar: Lecanactis subabietina, pruina K+ yellow Opegrapha vermicellifera, all chemical reactions negative

Lecanactis abietina
Wessex Lichen Group meeting, New Forest, Hants. December 2012