Foliose lichen on cliff

Foliose lichen on cliff

Observation - Foliose lichen on cliff - UK and Ireland. Description: Light grey foliose lichen with circular thallus about 15cm across. Dark isidia increasing in density towards the centre of the thallus. Lots of patches of this lichen covering vertical cliff above the high tide mark. Possibly Parmelina pastillifera.

Light grey foliose lichen with circular thallus about 15cm across. Dark isidia increasing in density towards the centre of the thallus. Lots of patches of this lichen covering vertical cliff above the high tide mark. Possibly Parmelina pastillifera.