Four species of lichens and two species of lichenicolous fungi new to Belgium, and other species of interest for the country. Recent field surveys have yielded several species of lichens and lichenicolous fungi that are interesting or new to Belgium. Species new to Belgium are: Chaenothecopsis pusiola, Inoderma byssaceum, Rinodina biloculata, Porina rosei, Verrucula pusillaria and Xenonectriella physciacearum. Other species of interest for Belgium: Arthonia fuscopurpurea, Melanelia stygia and Unguiculariopsis lettaui were found in Belgium after 156, 49 and 172 years of absence respectively. Catillaria fungoides and Unguiculariopsis thallophila are new to Wallonia; Physciella chloantha is new to Flanders and was found in Wallonia after 152 years of absence. Several of these species (C. pusiola, I. byssaceum and P. rosei) are considered indicators of old forests and therefore deserve the implementation of protection measures.