Family: Ramalinaceae Species: Bilimbia sabuletorum Growth type crustose, granular. Photos: Over-growing moss on walls. Co. Cork, SW Ireland. White or pale grey, coarse or scurfy granular thallus, sometimes evanescent. Convex, +/- rounded apothecia, very variable in colour; discs can be pinkish-brown, brown to dark brown or black. Spores 3-7 septate, 18-40 x 5-8 µm, perispore often finely-warted. Microscope photograph below. Chemical reactions negative. Found growing on plant debris or over moss on calcareous rocks, turf or mortared walls. Also occurs on shaded trunks of old trees. Similar: Mycobilimbia sphaeroides is an old woodland species, spores (0-)1(-3) septate

Microscope photograph

Above: Bilimbia sabuletorum. August 2009, January and April 2012