Order: Teloschistales       Family: Teloschistaceae Species: Scythioria phlogina (Caloplaca phlogina) Growth type crustose. Identified by Brian Coppins Photos: On Sorbus. Bandon, Co. Cork, SW Ireland. Thin, smooth thallus, whitish-grey to pale yellow, sometimes with shallow, bullate aureoles. Prothallus absent. Pale greenish-yellow soralia can spread to cover whole thallus. Soredia 30-50 µm diam. Apothecia 0.3-0.8 mm diam, discs deep yellow, +/- white-pruinose, margins often lacking soredia when mature. Spores 10-13 µm. Previously recorded on Elm bark, rare, declining. Old records from Co. Laois, Co. Fermanagh and East Donegal. Similar: Caloplaca citrina s.l is saxicolous with larger soredia, Caloplaca flavocitrina has distinct squamules, sorediate at tips

Scythioria phlogina (Caloplaca phlogina) May 2010