Lecania cyrtella (Ach.) Th.Fr.
Lecidea cyrtella Ach., Meth. Lich.: 67 (1803).
Thallus white to pale grey, very thin, wrinkled-roughened, in parts shining, matt in others, effuse or immersed, corticolous. Apothecia very small, 0.25-0.5 mm diam., disc pale pinkish-fawn to red-brown, ± translucent when wet, convex at maturity, ± plane at first, margins white or pale grey, crenulate, often excluded at maturity. Ascospores narrowly ellipsoid, 1-septate (rarely 3-septate), curved at maturity, 9-16 × 4-5 µm.
N: S: On deciduous, introduced trees. Very much undercollected and poorly known.
Cosmopolitan
