Pseudevernia furfuracea (L.) Zopf. var. ceratea (Ach.) D. Hawksw. forme saxicole.
Differs from Pseudevernia furfuracea var. ceratea lignicolous form by its habitat (highly exposed rocky ridges of the Monts d'arrée), lobes often comparatively wide, notably towards the thallus margin, whitish, isidia (even towards the base of branches) scarse or very small. Seems to be related to Pseudevernia furfuracea var. ceratea lignicolous by intermediate specimen.*