Rhytisma americanum is a species of ascomycete fungus in the family Rhytismataceae. It was described in 1998 by W. Hudler and M. Banik in the journal Mycotaxon. The species belongs to the genus Rhytisma, a group of tarspot fungi within the order Rhytismatales.
Rhytisma americanum has been recorded from North America. Occurrences are documented in fungus collection databases and biodiversity aggregators.