A recent field trip to the adjacent states of Maranhão, Pará and Tocantins yielded the following undescribed lichens: Buellia lichexanthonica, Chrysothrix citrinella, Cryptothecia isidioxantha and Heterocyphelium triseptatum (which is also reported from Tanzania). In addition, 127 species are reported new to Tocantins state, 126 to Maranhão and 73 to Pará; 22 of these are first records for Brazil. viz. Astrothelium ferrugineum, A. nigratum, A. norisianum, Bathelium inspersomastoideum, Bulbothrix sipmanii, Caloplaca oxfordensis, Collema rugosum, C. texanum, Diorygma erythrellum, Graphis atrocelata, G. deserpens, G. hiascens, G. norstictica, Lecanographa subcaesioides, Lecanora jamesii, Platygramme computata, Platythecium suberythrellum, Porina coralloidea, P. hibernica, Staurothele arenaria, Synarthothelium cerebriforme and Verrucaria margacea. The new combination Gassicurtia endococcinea is also made; it is the first saxicolous member of this genus.