Thelidium rivulicola (Nyl.) Mig.

Syn.: Arthopyrenia rivulicola (Nyl.) Arnold, Verrucaria rivulicola Nyl.
Lichenised. Poorly known taxon.
Substrate:
Altitudinal distribution: montane belt (potential vegetation: deciduous forests dominated by Fagus sylvatica and closed coniferous forests with Picea abies)
Note: a species with a whitish, subfarinose thallus, hemispherically protruding perithecia (to c. 0.25 mm in diam.), and 1-septate, oblong ascospores (to c. 30 µm long); on periodically submerged calcareous stones, rare in Western and Central Europe, including the Alps (Germany).
Germany: Oberbayern;