Lecania leprosa

Lecania leprosa is a species of saxicolous, crustose lichen in the family Ramalinaceae. It occurs in Eastern Europe.

Taxonomy

The lichen was formally described as a new species in 2008 by Rikke Reese Næsborg and Jan Vondrák. The type specimen was collected from Devín, where it was found growing on the mortar of a northwest-exposed wall. The species epithet leprosa means "scurfy" or "scaley", and refers to the form of the lichen thallus.

Lecania leprosa has an irregularly areolate, relatively thick crust-like thallus with a colour ranging from pale grey, grey, lead-grey, blue-grey, brown-grey, to dark grey. The species is usually encountered in the sterile form, but in the few instances that apothecia have been recorded, they are typically 0.31–0.47 mm in diameter with a brown to dark brown disc and a margin that is the same colour as the thallus. Ascospores are hyaline and ellipsoid with a single septum, and dimensions of 9.9–11.3 μm long by 3.5–4.0 μm wide. The lichen thallus contains an acetone-insoluble pigment called Hertelii-green.

Lecania leprosa has been recorded from Austria, Czech Republic, Romania, and Slovakia, where it grows on concrete, mortar, and limestone.