Halegrapha (Ascomycota: Graphidaceae), an enigmatic new genus of tropical lichenized fungi dedicated to Mason E. Hale Jr.

The new genus Halegrapha is introduced, with six species (five new species and one new combination) from Australia, the Philippines, Malaysia, Kenya, Mexico, and the United States: H. chimaera Rivas Plata & Lucking (type species; Philippines), H. floridana Common & Lucking (United States: Florida), H. intergrapha Hale ex Lucking (Malaysia), H. kenyana Kalb & Lucking (Kenya), H. mexicana A. B. Pena & Lucking (Mexico), and H. mucronata (Stirt.) Lucking (Australia). The genus resembles Graphis morphologically in the strongly carbonized, black lirellae and white-grey thallus strongly encrusted with calcium oxalate crystals, but has a Phaeographis-type hymenium (clear in two species) and ascospores, making it a 'chimera' between the two genera. Molecular data suggest the genus to be closely related to Phaeographis and allies but genetically distinct from any of the genera currently recognized, including Platygramme.