Thelidium aphanes J. Lahm

Lichenised. Poorly known taxon.
Substrate: calciferous rocks
Altitudinal distribution: submediterranean/colline belt (potential vegetation: mixed deciduous forests dominated by Quercus and Carpinus)
Note: a species of the Th. incavatum-group with an endolithic, whitish thallus, entirely immersed perithecia with punctiform ostioles, and 3-septate, less than 40 µm long ascospores; on pebbles of limestone, with scattered records in Central Europe, including the Eastern Alps (Austria).
Austria: Oberösterreich;