Syn.: Lithoicea nigrescens (Pers.) A. Massal. var. umbrina A. Massal.; incl. Verrucaria nigroumbrina Servít f. acrotella (A. Massal.) Servít
Lichenised. Poorly known taxon.
Substrate: calciferous rocks
Altitudinal distribution: submediterranean/colline belt (potential vegetation: mixed deciduous forests dominated by Quercus and Carpinus)
Note: a calcicolous species with a thin, greyish-brown to brown, spreading, rimose to areolate thallus, the basal layer brown-black or lacking in young areoles, only slightly protruding ascomata covered by a thin thalline layer, an involucrellum adpressed to the perithecial wall, reaching down to the base and fusing with the basal layer, and oblong to ellipsoid ascospores (to c. 25 µm long); only known from the Eastern Alps (Italy), and from Liguria (outside the Alps).
