Order: Pertusariales Family: Pertusariaceae
Species: Pertusaria hemisphaerica
Photos: On Chestnut trunk. Macroom, Co. Cork, SW Ireland.
Identification confirmed by B. Coppins.
Thallus whitish or pale bluish-grey, smooth or warted with distinct zoned white prothallus. Conspicuous convex soralia, often becoming confluent. Soredia granular, pale bluish-grey or concolorous with thallus. Apothecia are unknown.
On well-lit or slightly shaded, mature, rough-barked trees, often near base of trunk. Rare on rock.
Soralia K-, C+ carmine-red, KC+ red, P-, UV+/- glaucous
Similar: Loxospora elatina. Damp, acid bark, K+ yellow.
Ochrolechia androgyna. Yellow soredia, C+ red, KC+ orange-red.
Pertusaria hemisphaerica February 2010