Hi,

I'd like to know your opinion of this fungus. I think it's a Didymella due to it's small, quite flat ascomata, bitunicate asci, two-celled spores which are constricted at the septum and the present paraphysoides. However, I don't know a species of this genus growing on wood so I hope you can help me.

The spores are 17,5-21,5 x 6,5-7 µm, hyaline, two-celled, with one oil drop per cell, constricted at the septa and without any sheaths or appendages. One cell of the spores is often bigger than the other and the septum is not always perfectly in the middle of the spores. The asci are inverted clavate and bitunicate, I didn't see asci with ascospores. Paraphysoides were present. The ascomata were small (around 200 µm), partly immersed and glabrous. I found it on an Alnus-stem.

Best wishes,

Gernot