Order: Pyrenulales       Family: Pyrenulaceae Species: Pyrenula macrospora Growth type crustose. Photos: The Burren, Co.Clare and Co. Cork, Ireland. Waxy olive-brown to creamy yellow thallus with flecks of white pseudocyphellae. Mosiac-forming, black prothallus. Globose black perithecia to 1mm, becoming prominent with a visible ostiole when mature. Asci are 8-spored, the spores brown, 3-septate with distinctive locules, 25-35 x 8-12 µm. Micro photographs below. K+ yellow, UV+ yellow or orange or UV- Common throughout Ireland on shaded, smooth-barked trees. Similar: P. chlorospila has smaller perithecia. P. laevigata, white or pale cream thallus without pseudocyphellae. P. occidentalis has a yellow-brown to creamy orange thallus with brownish flecks

Microscope photographs



Pyrenula macrospora. April and November 2009, January 2012