Arthonia radiata Arthoniaceae
Arthonia radiata

Growth type crustose
Chemical results: Negative

Pioneer species, very common on smooth-barked trees and shrubs.

The small patches of white, pale-grey or olive-brownish thallus are often surrounded by a black prothallus. Crowded, black, rounded or star-shaped apothecia are not pruinose. Asci are 8-spored, the spores 3-septate, upper cell not enlarged, 15-20 x 5-7 Ám. Micrographs below.

Similar: Coniocarpon fallax (Arthonia elegans). Thallus often tinged yellowish, apothecia K+ red-purple, spores (2-)3-4(-5) septate


Arthonia radiata

Arthonia radiata

Microscographs
Arthonia radiata

Arthonia radiata
Arthonia radiata
Dorset. 2012, 2016, 2019

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