Species: Enterographa crassa
Photos: The Burren, Co. Clare and Co. Cork, Ireland
Grey, brown or olive-greenish thallus with black prothallus. Thallus can be smooth or lumpy, often forming mosaics. The minute dark-brown, embedded, apothecia (0.1-0.3mm) form dots or thread-like lines. The asci are 8-spored, spores 5-7 septate, 28-38 x 4-6 Ám. Microscope photographs below.
Chemical reactions negative.
Common on shaded trees, occasional on damp, sheltered rocks.
Similar: E. hutchinsiae. Usually on rock, apothecia 0.3-1mm long.