Irish lichens

Bryostigma lapidicola, Arthonia muscigena

Order: Arthoniales       Family: Arthoniaceae

Species: Bryostigma lapidicola (Arthonia muscigena)

Growth type crustose. Photobiont chlorococcoid.
Photos: On Weigela twig. Knockgorm, Co. Cork, SW Ireland.
Identified by John Douglass

Found as small patches of thin olive-grey or greyish-brown minutely granular thallus with tiny convex black apothecia. Spores 1-septate with upper cell shorter and broader than lower, 8-12(-14) x 2.5-4 µm. Microscope photograph below. Chemical results negative

Usually found on Sambucus (Elder) twigs but also on Acer and Ulmus trunks


Arthonia muscigena

Arthonia muscigena

Microscope photograph
Arthonia muscigena
Bryostigma lapidicola (Arthonia muscigena) . May 2012

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