Hypoxylon commutatum Nitschke.

This fungus is not illustrated for it is known only from the type collection from Germany (on Carpinus ?). It is reported by Ju & Rogers (1996) as pulvinate to hemispherical with surface dark brick (60) and orange (7) KOH-extractable pigments. Asci lack apical rings and ascopsores are 9-11 x 4.5-5.5 µm.

HPLC anlyses proved it belongs to the same chemotype as H. fragiforme and H. howeianum with mitorubrin and orsellinic acid and absence of BNT and rubiginosins (Stadler, pers. comm.), which is in agreement with morphological features. Its main differences with H. fragiforme are the slightly smaller ascospores and asci lacking apical ring. Fresh collections would be necessary to assess the relationships of H. commutatum with H. fragiforme and H. howeianum.