The upper surface is pale greyish-green, smooth (glabrous), and glossy, turning chestnut brown over time in herbaria.

[2] The secondary chemistry of Pannaria phyllidiata includes vicanicin as the major compound and trace amounts of unidentified terpenoids.

[2] This lichen species is primarily found in New South Wales, Australia, with single occurrences in Victoria and Queensland.

It is associated with various tree species, including Nothofagus, Eucalyptus, Olearia, Pomaderis, Trochocarpa laurina, Lomatia ilicifolia, and Bedfordia salicina.

[2] Pannaria minutiphylla, found in New Zealand, has smaller phyllidia (0.2–0.3 mm tall) that are less erect, and ascospores that measure 6.5–9.0 by 15–21 μm.