Verrucaria tuerkii Breuss

Lichenised. Poorly known taxon.
Substrate: bark
Altitudinal distribution: submediterranean/colline belt (potential vegetation: mixed deciduous forests dominated by Quercus and Carpinus)
Note: a species with a thin, greenish-grey, spreading thallus, ascomata at first immersed but later hemispherically protruding with the naked, black apex (to c. 0.2 mm in diam.), an adpressed involucrellum reaching down to the base of the perithecium and there somewhat spreading, and oblong to ellipsoid ascospores (to c. 30 µm long); on bark Fagus in a humid mixed forest, so far only known from type locality in the Eastern Alps (Austria).
Austria: Niederösterreich (incl. Wien);