Family: Lecanographaceae Species: Alyxoria culmigena (Opegrapha herbarum) Growth type crustose. Photos: Ardnagashel and Macroom, Co.Cork, Ireland. Thin or inconspicuous pale grey, brownish or olive-green thallus.The small, scattered lirellae are usually simple, less frequently branched. Slit-like discs becoming fully open, occasionally +/- green-pruinose. Pycnidia are very rare. Asci are 8-spored, spores 3-septate, 18-25 x 5-8 µm with thin perispore. The second cell is often longer and broader than the other cells. Microscope photographs below. On acid to basic, smooth, often shady bark, on plant stems (especially brambles) and on sandstone. Reactions negative. Similar: Alyxoria ochrocheila (Opegrapha ochrocheila). Second cell broadest but same length as other cells

Microscope photographs

Alyxoria culmigena (Opegrapha herbarum) March and May 2010