Separates subgenus Annulata into a new genus, Annulohypoxylon.

A list of the species is included.

Annulohypoxylon differs from Hypoxylon in having a carbonaceous stromatal layer discretely enclosing each perithecium. The ostioles are always higher than the surrounding stromatal surface and usually encircled by a distinct or highly reduced annulate disk. The perispore, when dehiscing, has a distinct thickened area about 1/3 of the way along the ascospore.