Hello, 

I found this a few days back, Czech Republic, riparian forest, ca. 220 m asl., on a dead 1,5cm Padus avium branch hanging about 1,5 m above ground. 

KOH-, LA-, perithecium wall one-layered, perithecial crown seems to have smooth margin, tetrasporic asci, fusiform spores probably with low verrucose or spinulose ornam. 
There were two kinds of anamorphs: One (Acremonium-like?) grew directly from the perithecia, another (pointed larger conidia) made a whitish hyphal lumps. 

Could it be I. tetraspora? I have very little experience with nectrioid fungi.

Thanks a lot in advance.
Viktorie