Canoparmelia lichens have grey or rarely yellow-green
thalli containing the secondary chemicals
atranorin and
chloroatranorin, or rarely
usnic acid, in the
cortex. The thallus is made of more or less rotund lobes that are 3.0–5.0 mm wide and lack
cilia; the
medulla is white. The underside of the thallus is black or brown with naked brown margins and simple
rhizines of the same colour.
Canoparmelia produces small
ellipsoid ascospores that measure 10–14 by 6–8
μm. The
conidia are fusiform (spindle-shaped) or bifusiform, measuring 7–10 μm long. ==Species==