Hi, 
I would like help with determination.
Perithecia singly or small groups, distale zone absend, subepidermal, only ostiole prominent on surface, 620 um in diam., 300 um hight, ostiole 200-500 x 100 um, a long filiform, wall of ascocarp textura angularis, cells 15-20 x 10-14 um. Asci (37)40-43(48) x (7)7,6-9(9,5) um, ascospore biseriale, (12)13-15(16) x (2,8)3,1-4(4,6) um, Q=4,1, with polar apiculum 4-5 um long. I thought, that it is somewhere from the Diaporthales, but microscopic structures are diferent or somewhere with group Apiognomonia errabunda, Ophiognomonia rubi-idaei, Gnomoniopis chamaemori, comari or fructicola, but its microscopic structurs are by me different. Sub. dead stems of Rubus idaeus.