Abstract
As part of the Gorgona Island Natural National Park Scientific Expedition, an inventory of lichens was carried out. 83 lichen species, included in 34 genera and 14 families, were found. All of the reported species are registered for the first time for the Gorgona Island Natural National Park; 31 species are registered for the first time for Colombia and 61 for Cauca. The genus Eugeniella is registered for the first time for Colombia. The genera with the most number of species were Pyrenula (7 species), Tricharia (6), Strigula, Herpothallon (6) and Graphis (5), whereas 24 genera were represented by only one or two species. The Families Gomphillaceae and Graphidaceae were the best represented with 18 and 17 species respectively. 53% of species were corticolous, 45% were foliicolous and 3% were saxicolous. The majority of corticolous lichen species were found in the road leading to Mirador (14 species). The vast majority of lichens (93%) presented crustase thallus, whereas foliose, gelatinous and filamentous forms where least abundant (4, 3 and 1% respectively). Neither fruticose nor dimorphic thallus lichens were found. Ampliotrema amplius (Nyl.) Kalb, which is frequent in primary or less disturbed forests was found.