Staurothele nantiana (B. de Lesd.) Zschacke

Syn.: Polyblastia nantiana B. de Lesd.
Lichenised. Poorly known taxon.
Substrate: calciferous rocks,
Altitudinal range: from the submediterranean/colline belt (potential vegetation: mixed deciduous forests dominated by Quercus and Carpinus) to the subalpine belt (potential vegetation: open, taiga-like forests dominated by Larix decidua and/or Pinus cembra and Rhododendron)
Note: a species recalling Verrucaria hochstetteri, with a whitish-grey, epilithic thallus, perithecia immersed in hemispherical thalline warts, spherical hymenial algae, and 8-spored asci; on occasionally submerged limestone rocks; all known records are from SW Europe, including the Western Alps (France).
France: Savoie;