Arthonia pruinata Arthoniaceae
Arthonia pruinata

Growth type crustose
Chemical results: K-, C+ red, P-, UV-

Can be dominant on the dry bark of old, well-lit trees (e.g Oak, Sycamore). Most frequent in the south of England.

Matt or powdery light-grey to brownish thallus, the immersed apothecia pink or brown and usually very pruinose. Spores remaining colourless, (3-)4-5 septate, 13-22 x 4.5-7 Ám. Upper cell not enlarged. Micro photos below.

Sterile specimens resemble Schismatomma decolorans which is C-


Arthonia pruinata

Arthonia pruinata

Arthonia pruinata

Microscope photographs
Arthonia pruinata, spores

Arthonia pruinata, spores
Arthonia pruinata
Holton Lee and Lytchett Minster, Dorset. February 2013, December 2016

All images used are copyright. Please contact me if you find errors.