Identification key
Physcia adscendens/Physcia tenella
(1) Physcia adscendens / Physcia tenella
Description
Thallus
Foliose, up to 2-3 cm, sometimes confluent with other thalli, can cover large areas, lobes 0.5-1.5 mm broad, margins with pale cilia, darker at the end

Color
Pale gray
Reproduction
Apothecia: infrequent, 1-2 mm in diameter, disc black and pruinose
Soralia: numerous, greyish, slightly greenish on the edges of the lobes
Isidia: absence
Risk of confusion
Anaptychia ciliaris is larger and has a fruticose thallus
Physcia leptalea has no soralia but often has apothecia
Physcia aipolia / P. stellaris is more attached to the substrate and lacks cilia

Ecology
Substrate
On bark, sometimes on rock or artificial substrate

Habitat
Nitrophilous

Occurrence
Very common, widespread in urban areas

Air pollution
Resistant to pollutants

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