The lichen has a wrinkled
thallus, greenish to brownish gray in colour, measuring wide, comprising flat, overlapping lobes that are 2–5.5 mm wide. It has roughly spherical laminal structures the authors call "granules" that measure 0.1–0.25 mm in diameter, and originate from the edges of the wrinkles. These granules, which are the same colour as the thallus, may be absent in some thalli, or densely crowded in others.
Apothecia are mostly located on the margins on the thallus; they are up to 1.2 mm in diameter. The
ascospores are
ellipsoid with sharp tips, measuring 26.5–32.5
μm; they have 3 to 5 transverse
septa and 1 or 2 longitudinal septa. The
cyanobacterial partner of
Leptogium kalbii is
Nostoc; their cells measure 5.0–6.5 by 5.0–6.5 μm. ==References==