Porina calciseda (Bagl. & Carestia) Lettau

Syn.: Sagedia calciseda Bagl. & Carestia, Verrucaria calciseda (Bagl. & Carestia) Stizenb. non DC.
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 long-forgotten species with a rather thick, chalky, dirty white, continuous to rimose thallus, immersed, black perithecia with a flattened ostiolar region, sparse filiform paraphyses, lanceolate 8-spored asci, and elongate-fusiform, straight to slightly curved, 3-5-septate, hyaline ascospores measuring 29-36 × c. 4 µm; only known from the type collection, on limestone, which would be worthy of further study.
Italy: Piemonte;