Sillia ferruginea

A saprophytic species on decaying wood of deciduous trees such as beech or hazel, with blackish perithecia deeply immersed in tissue, 0.3 to 0.6 mm in diameter, aggregated in stromata 1.5 to 4 mm in diameter, erupting to the outside through cylindrical necks.

Inside the perithecia are the asci, which are cylindrical, eight-spored, short-stalked, with parallel to fasciculate spore arrangement inside the ascus occupying almost the entire ascus length.

Ascospores filiform, with slightly pointed ends, smooth, hyaline, thin-walled, 50 to 90 µm long, 3.5 to 4.5 µm wide, with 3 to 7 transverse septa and abundant oil droplets (guttules) inside.