Discovering the lichen diversity of a remote tropical island: working list of species collected on Reunion (Mascarene archipelago, Indian Ocean)

463 lichen taxa are reported from the island of Reunion (Mascarene archipelago) in the Indian Ocean. This report is based on extensive collections recently made by the authors or hosted in B and LG. A total of c. 600 species is estimated for the number of lichenized fungi present on the island; although this is a low figure for a varied tropi- cal area, this is plausible due to its small size and remoteness. The significance of the lichen diversity of the island lays in its endemics, which need further study for a reliable assessment, and in the occurrence of a poorly known southern hemisphere element (“austral” species). The discovery of the following in Reunion is of special interest as it considerably enlarges their distribution range: Anzia corallophora, Caloplaca caesiosorediata, Coccocarpia delicatula, Fuscopannaria praetermissa, Gomphillus morchelloides, G. pedersenii, Gyalideopsis bispora, Heterodermia koyana, Hypotrachyna evansii, Lithogyalideopsis zeylandica, Lobaria asperula, Megaloblastenia marginiflexa var. dimota, Menegazzia capitata, Myeloconis erumpens and Pannaria squamulosa.