Knowledge leads to protection: anuran composition and conservation of the ‘Brejos de altitude’ of Northeastern Brazil

The ‘Brejos de altitude’ (BA) are mountains that harbor rich biodiversity, including endemic and threatened species. However, some of them remain understudied, suffering high anthropogenic pressures. To verify the composition, richness, conservation status, and biogeographic patterns, we compiled information about the anurans from 16 BA in Northeastern Brazil. We used data from the 28 literatures, consulted the herpetological collections, and sampled three mountains in the Ceará state, Northeastern Brazil. We compiled 73 species of anurans distributed in 12 families; hylids and leptodactylids are the most representative. The highest richness was found in Brejo dos Cavalos and Madre de Deus, located in the Pernambuco state; Ibiapaba, Baturité and Maranguape, in the Ceará state. The BA harbor five endemic frogs, three of which are threatened species, which were not considered protected since they occur outside strictly protected areas. The BA from eastern Pernambuco and Paraíba states have a pronounced influence of Atlantic Forest species. In contrast, Ceará’s BA is the most distinct, with a unique composition of endemic and threatened species and a higher influence of Caatinga elements. Our results show the urgent necessity of the implementation of new protected areas in these mountains.