Green Elfcup - Chlorociboria aeruginascens
Greenish blue cup fungi with off-centered stems. They were about 5 mm wide.
This species contains a quinone pigment called xylindein, which is the reason for the characteristic bluish-green stain that occurs on wood that's infected by this species.
Habitat: Rotting birch
''Chlorociboria aeruginascens'' is a saprobic species of mushroom, commonly known as the green elfcup or the green wood cup because of its characteristic small, green, saucer-shaped fruit bodies. Although the actual fruit bodies are infrequently seen, the green staining of wood caused by the fungus is more prevalent.