: Arthonia stellaris.

Arthonia stellaris grows on smooth bark of deciduous trees in oceanic forests and woodlands from Rogaland to Møre og Romsdal. It is recognized by reddish brown to brown-black, narrowly elongated to star-shaped apothecia on a thin thallus with trentepohlioid photobiont. The brown and warted spores are divided by 3–4 transverse septa, the apical cell is enlarged.

Arthonia stellaris Kremp.
Creative Commons Attribution | Andreas Frisch | NTNU Vitenskapsmuseet | Håkon Holien | NORD Universitet
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