Silhouette (19.9 km2) is the third largest island in the Seychelles (Indian Ocean), its anitic mass rising sharply to a maximum of 751 m and covered by dense rainforest. Its lichen flora of 141 taxa (129 determined to specific level) is pantropical and poorly related to the neighbouring islands of Aldabra and Chagos. Although the island is subject to limited human pressure, its vascular flora is under threat due to the spread of Cinnamomum; however, tree’s bark and leaves provide suitable substrata for lichens. A study of the comparative lichen floras of Cocos and Calophyllum showed the former to support not only a greater species diversity but also significantly more host-specific lichens. Almost all species reported here are new records for the Seychelles Archipelago. Most are pantropical lowland species, but some represent rather unexpected range extensions. New to Africa are e.g. Anisomeridium musaesporoides, Byssoloma annuum, Caloplaca leptozona, C. pulicarioides, Cryptolechia subincolorella, Gyalideopsis parvula, Melaspilea diplasiospora, Mycomicrothelia captiosa, Pyrenula parvinuclea, Rinodina perminuta and Tomasellia eschweileri