looking for Cosmospora ustulinae on Ustulina (Kretzschmaria) deusta I found this fungus. The spores are too large for C. ustulinae. For Dialonectria episphaeria the spores are too coarsely warted and even too large. There are some other species that could potentially grow on Ustulina but with smooth spores (e. g. Cosmospora flavoviridis s. str.).

Perithecia: red, with papilla, no disc, collapsing laterally up to the papilla
Ascospores: 8-14 x 3,5-5 (5,5) µm, pale brown, coarsely warted, even in larger hyaline ascospores, larger ascospores tend to have acute ends, but also smaller ones with rounded ends are pale brown
Host: Ustulina (Kretzschmaria) deusta

Is it still one of the species mentioned above or did I find something else?

Regards
Steffen