Objective: The present work aimed to describe, comment, and illustrate two new lichenized species of Ascomycota. Method: Morphological analyses of the samples were performed at the Laboratory in the State University of Bahia (UNEB), Campus VIII. The lichen thalli were observed using a stereomicroscope (Zeiss); chemical treatments were performed to observe the microscopic structures of the lichens after exposure to 10% KOH (potassium hydroxide), lactophenol (cotton blue), Melzer’s reagent, chlorine, and viewed under UV light. The chemical compositions of the lichen were examined using thin layer chromatography (TLC) at the Biochemical Laboratory of the Federal University of Pernambuco. Results and conclusion: Stirtonia juaensis and Cryptothecia paramacrocephala are two new lichenized species of Ascomycota found colonizing the plants Spondias tuberosa Arruda (Umbuzeiro) and Piptadenia moniliformis Benth. (Quipembe) in the Caatinga phytogeographical domain near the village of Juá in the municipality of Paulo Afonso, within the Raso da Catarina Ecoregion in northern Bahia State, Brazil. Originality/value: Research related to lichen taxonomy in Brazil is still scarce, especially in the Caatinga. The new species of Stirtonia and Cryptothecia described and illustrated in this work expand the knowledge about fungi in Brazil. Keywords: Caatinga, Lichen, Taxonomy, Stirtonia, Cryptothecia.