online flora
Parmelia saxatilis
(1) Parmelia saxatilis
Description
Thallus
Foliose, up to 20 cm in diameter, loosely adherent to the substrate, squared-lobed around the edge, with lobes 3 mm wide, with a network of clearly visible whitish fissures (pseudocyphellae)

Color
Grey-blue upper side (darker in very sunny areas), black underside
Reproduction
Apothecia: rare, reddish-brown disk, isidial margin
Soralia: —
Isidia: numerous, slightly browned at the tip, of various shapes
Risk of confusion
Parmelia sulcata, more common, sorediate, also having pseudocyphellae
Ecology
Substrate
On bark and non-calcareous rock

Habitat
Heliophilous and acidophilous

Occurrence
Common

Sensitivity to air pollution
Moderately sensitive to pollution

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