Family: Acarosporaceae Species: Acarospora impressula Growth type crustose. Photos: On granite boulder at Black Head, The Burren, W Ireland. BLS Burren meeting 2009 Small patches or streaks of red-brown thallus with small, angular areoles less than 2mm wide. Dark-brown to blackish apothecia. Asci c. 100-spored, spores 3-4 x 2-2.5 µm. Chemical reactions negative. Scarce, mainly coastal on siliceous rocks, especially granite. Similar: A. fuscata K-, C+ red, KC+ red

Acarospora impressula. BLS Burren meeting April 2009 and immediately above Co.Cork June 2009