Peltula species occur in arid and semi-arid environments, with new species being regularly described worldwide. Lichen diversity is being studied in the diverse but poorly known Midwest region of Brazil, and new species and records are being proposed. In this paper, Peltula anthracina is proposed as new to science, and P. leptophylla and P. lingulata are reported as new records from Mato Grosso do Sul state. As it is a region highly threatened by the expansion of agricultural activities, the authors highlight the importance of the conservation of native flora to preserve lichens’ hidden diversity. Key words: arid habitat; cyanolichen; diversity; fire forest; new species.