Verrucaria pustulifera Servít

Lichenised. Poorly known taxon.
Substrate: calciferous rocks
Altitudinal distribution: montane belt (potential vegetation: deciduous forests dominated by Fagus sylvatica and closed coniferous forests with Picea abies)
Note: a calcicolous species with a thin, continuous to irregularly rimulose, smooth to granulose, grey thallus, ascomata (to 0.25 mm wide) immersed into slightly protruding verrucae, for the major part covered by a thin thalline layer, involucrellum slightly spreading towards the lower rim and reaching down about one third of the perithecium, and oblong ascospores (to c. 35 µm long); rarely recorded in Central Europe, including the Eastern Alps (Austria).
Austria: Niederösterreich (incl. Wien);