Lecidella scabra

Lecidella scabra is a species of nutrient-rich, siliceous rocks, or occasionally on wood and artificial substrates. Records within the recording area include wave-splashed sandstone blocks at Penclawdd, slag at Loughor and copper mine spoil in the Swansea Valley. This crustose lichen has a thin, granulose-verrucose to areolate thallus, which is grey-greenish. Yellow-greenish soralia are often abundant, sometimes confluent, but may forming small clumps. The grey prothallus is more or less distinct. The black apothecia are sessile, often convoluted to sub-gyrose, becoming excluded. 

Listed by Alan Orange in Flora of Glamorgan (Wade et al, 1994).