805 infrageneric taxa, 777 of lichenized fungi, 23 of lichenicolous fungi, and 5 of non-lichenized fungi belonging to genera including also lichenized forms are reported from the eastern part of the Italian Peninsula. Six regions were surveyed, with a total of 130 collecting sites: Marche (35 sites, 420 taxa), Umbria (2 sites, 106 taxa), Abruzzo (23 sites, 460 taxa), Molise (11 sites, 304 taxa), Puglia (38 sites, 424 taxa) and Basilicata (21 sites, 337 taxa). These regions were among the lichenologically least known in Italy; their floras, compared with data provided six years ago in the first checklists of Italian lichens, have increased as follows: Marche, 159% (presently known flora: 484 taxa); Umbria, 455% (261 taxa); Abruzzo, 76% (589 taxa); Molise (305 taxa); Puglia, 48% (566 taxa); Basilicata, 115% (464 taxa). Fourteen taxa (Anema moedligense, Arthonia anombrophila, Aspicilia desertorum, Caloplaca veneris, Cresporhaphis wienkampii, Dirina cretacea, lmmersaria uzbekica, Lecanora congesta, L. graeca, Lecidea albohyalina, Peccania salevensis, P. riruncula, Thelidium dionantense, and T. impressum) are new to the Italian lichen flora. Earlier hypotheses about a basic difference in the lichen floras of Western (Tyrrhenian) and Eastern (Adriatic) peninsular Italy, the former with a higher incidence of subtropical-suboceanic species, are confirmed by the new data. Keywords: Flora, Italy, Lichens.