Pertusaria pertusa, Duror, 29/11/2015

Back onto the lichenised side of life, this is a nice - if common - species with a penchant for big spores - only two per ascus. It came from a small deciduous twig. Fortunately the fact that the apothecia look a bit like perithecia is caught in Dobson and he manages to sweep it back into the fold early in the key.

The Flora notes that subglobose warts with multiple apothecia per wart and two spored asci is pretty much to separate it from other species which might resemble it.