Parmotrema mellissii is a widely distributed species of corticolous lichen in the family Parmeliaceae. It was first described by Carroll William Dodge in 1959 as a species of Parmelia. Mason Hale transferred it to the genus Parmotrema in 1974. The type collection was made in Saint Helena. Parmotrema mellissii has a pale yellowish-buff coloured thallus at least 12abbr=onNaNabbr=on in diameter, comprising rounded lobes about 15 mm wide and long. It has been found in the southern U.S.A., the Neotropics from Mexico to Colombia and Brazil, Africa (including the Canary Islands and Kenya), Asia (Japan, Laos, the Philippines), Australia and Oceania.