Pyrenula gahavisukana is a species of corticolous (bark-dwelling) crustose lichen in the family Pyrenulaceae. Described as a new species in 1997 by André Aptroot, it is found in the Eastern Highlands Province of Papua New Guinea. As of its original publication, it was known only from the type locality in Mount Gahavisuka Provincial Park, where it was collected in a mossy mountain forest at 2400 m elevation. It is suspected to have a pantropical distribution, and has since been recorded from Costa Rica, Colombia, and Brazil.