Order: Ostropales Family: Phlyctidaceae
Species: Phlyctis argena
Photos: On Lime. Bandon, Co. Cork, SW Ireland.
Whitish to pale grey-green, thin or thick thallus with paler prothallus. White to greenish, fine to coarsely-granular soredia, few or abundant and covering thallus centre. Apothecia rare, discs greyish-black, pruinose with thin margins. Can cover large areas.
Widespread, usually found on well-lit deciduous trees, rarely on conifers. Occasional on shaded, +/- basic rock and walls.
K+ yellow turning red, C-, KC+ red, P+ orange-red, UV-
Similar: Phlyctis agelaea. Soredia absent, apothecia frequent.
Phlyctis argena December 2009