With 566 species, the neotropical genus Pristimantis is the most speciose vertebrate genus. As a result of its striking diversity, taxonomic reviews remain a challenge. Herein, we present an updated phylogeny of the Pristimantis lacrimosus group and describe a new species from Llanganates and Sangay National Parks. We also report, for the first time, the phylogenetic position of Pristimantis degener, P. eugeniae, P. katoptroides, and P. petersi. Based on our phylogeny, we add two species to the Pristimantis lacrimosus group. Through the integration of molecular and bioacoustic evidence, we describe a new species which was hidden under "Pristimantis petersi". Pristimantis petersioides sp. nov. is most closely related to Pristimantis petersi and an undescribed species from Peru. It can be distinguished from P. petersi by its advertisement call and large genetic differences (uncorrected p-genetic distances 7.9% to 8.4% for gene 16S). Moreover, the new species and P. petersi are not sister species. We suggest assigning the new species to the Endangered Red List category because it has a small distribution range with deforestation as result of agriculture and other anthropogenic influences.