Arthonia lapidicola Arthoniaceae
Arthonia fusca (Arthonia lapidicola)

Growth type crustose
Chemical results negative

Widespread on calcareous rocks and mortar in open habitats and also found on church windowsills below metal grilles.

The thin, greyish, pale fawn or olive-brown thallus is partly immersed or irregularly scurfy. Dark brown or blackish apothecia are usually 0.2-0.4 mm in diameter, spores 1-septate, 11-15(-18) x 4-7 Ám. Pycnidia can be few or numerous, the conidia bacilliform. Microscope photograph below.


Arthonia lapidicola

Arthonia lapidicola

Arthonia lapidicola

Microscope photograph
Arthonia lapidicola
Arthonia lapidicola
Wimborne Minster, Dorset. March 2017

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