Order: Capnodiales       Family: Mycosphaerellaceae Species: Stigmidium microspilum Lichenicolous fungus Photos: On Graphis scripta. Ballingeary, Co. Cork, SW Ireland. Irregularly shaped greyish-black patches composed of dark brown hyphae are scattered over the host thallus with small clusters of black perithecia at the centre of the larger patches. Asci are 8-spored, spores 1-septate, hyaline but becoming pale brown when over-mature, 14-19 x 4-5 µm. Microscope photograph below. Fairly common on Graphis scripta in humid woodlands in the west of Britain and in Ireland. Possibly also occurs on other Graphis species. Similar: Arthonia graphidicola also occurs on Graphis scripta.

Microscope photograph

Stigmidium microspilum on Graphis scripta. January 2010