The following corrections and amendments are made to the 2016 classification of lichenized fungi published in the previous issue of this journal. Four families are added: Harpidiaceae (Pezizomycotina incertae sedis), with the two genera Euopsis and Harpidium; Pleomassariaceae (Pleosporales), with the genus Splanchonema; Squamarinaceae (Lecanorales), with the two genera Herteliana (moved from Ramalinaceae) and Squamarina (moved from Stereocaulaceae); and Trichosphaeriaceae (Sordariomycetes: Trichosphaeriales), with the genus Cresporhaphis. The following previously overlooked genera are also added: Allophoron (Pezizomycotina incertae sedis), Cresporhaphis (Trichosphaeriaceae), Gabura (Arctomiaceae), Julella (Trypetheliaceae), Knightiella (Icmadophilaceae), Porpidinia (Lecideaceae), Protoroccella (Roccellaceae), Psoromidium (Pannariaceae) and Tremotylium (Arthoniales incertae sedis). The classification is adjusted for four genera: Asteroporum (moved from Pezizomycotina incertae sedis to Dothideomycetes incertae sedis), Eremastrella (moved from Psoraceae to Lecideaceae), Hosseusia (moved from Pannariaceae to Lecanoromycetes incertae sedis) and Joergensenia (moved from Lecanorales incertae sedis to Pannariaceae). Further, the following overlooked generic synonyms are listed: Buscalionia (= Marcelaria [nom. cons. prop.]), Degeliella (= Psoromaria), Dirinastrum (= Buellia), Gymnographa (= Phaeographis), Kroswia (= Fuscopannaria), Marfloraea (= Lepra), Medusulina (= Fissurina), and Phaeographina (= Pliariona); the genus Anapyrenium is discussed as a potential synonym of Thelomma. Species numbers are adjusted for nine genera: Austrella (Pannariaceae; 3 spp.), Icmadophila (Icmadophilaceae; 5 spp.), Lepidocollema (Pannariaceae; 23 spp.), Massalongia (Massalongiaceae; 6 spp.), Parmeliella (Pannariaceae; 70 spp.), Psoromidium (Pannariaceae; 1 spp.), Pyrgillus (Pyrenulaceae; 7 spp.), Siphula (Icmadophilaceae; 17 spp.) and Synarthonia (Arthoniales incertae sedis; 5 spp.). The fossil lichen Honeggeriella (complexa) is validated by adding MycoBank registration numbers, the validity of the genus name Pallidogramme (Graphidaceae) is discussed and confirmed, and the authorship of the name Thallinocarpon (Lichinaceae) is clarified. Several genera are (continued to be) considered non-lichenized, namely Chaenothecopsis (Eurotiomycetes: Mycocaliciales: Sphinctrinaceae), Limboria (newly lectotypified with L. constellata; Pezizomycotina incertae sedis), Naetrocymbe (Dothideomycetes: Pleosporales: Naetrocymbaceae), and Obryzum (Dothideomycetes incertae sedis: Obryzaceae); the status of the genus Pleurotrema (Dothideomycetes incertae sedis: Pleurotremataceae) is also discussed. Seven genera are corrected to have molecular data available: Adelolecia, Aspiciliopsis, Aspilidea, Crocodia, Parasiphula, Vezdaea and Xylopsora. With these corrections, the number of lichenized species is now tabulated at 19,409 and the number of fungal genera, families, and orders including lichens at 1,002, 119, and 40, respectively.