Leaves with small, raised black spots with a fine area of white tissue surrounding them, found mostly between the major veins.

Close-up of infected spots with blister-like, brown spore-producing bodies ("acervuli") within the spots.

Close-up of infected spots with blister-like, brown spore-producing bodies ("acervuli") within the spots.

Close-up of one infected spot with blister-like, brown spore-producing bodies ("acervuli") seen under dark-field observation.