online flora
Xanthoria parietina
(1) Xanthoria parietina
Description
Thallus
Foliose, up to 15 cm in diameter, with flat, rounded lobes, tight to the substrate

Color
From yellow-orange in the sun (2) to green in the shade (3)
Reproduction
Apothecia: frequent, orange disc
Soralia: —
Isidia: —
Risk of confusion
Xanthoria polycarpa, with a reduced and inconspicuous thallus, almost entirely covered with apothecia
Ecology
Substrate
On bark, sometimes on rock or artificial substrate

Habitat
Heliophilous and nitrophilous

Occurrence
Very common

Sensitivity to air pollution
Resistant to pollution

(2) Sunny form
(3) Shaded form
(4) Necrotic form