Phylogenetic diversity of the Pristimantis anaiae species group, with a description of a new species of Pristimantis (Anura, Strabomantidae) from Cerro Candelaria, Tungurahua, Ecuador

Abstract

Continuous field work on mountains in the upper Pastaza watershed, showed an unexpected cryptic diversity in the recently described Pristimantis anaiae species group. Based on molecular and morphological characters we describe a new frog species from the central region of the eastern Ecuadorian Andes. We present an updated phylogeny for the Pristimantis anaiae species group, based on widely used, ubiquitous, and available genes, three mitochondrial genes (12S rRNA, 16S rRNA, ND1) and RAG1 nuclear gene. Our phylogenetic hypothesis increases genetic diversity of the species group and shows two well-supported subclades. We show the relationships of the new species and include for the first time Pristimantis maryanneae, belonging to a clade related to P. resistencia + P. glendae. Our phylogeny shows that new species, from Cerro Candelaria, is more closely related to P. kunam from Sangay National Park and differs from it by having a less conspicuous dorsolateral row of enlarged tubercles, and sacral oval marks surrounded by thin white pale lines. The new species and two additional undescribed species occur on the south side of the Rio Pastaza Valley, at Cerro Candelaria within the Llanganates – Sangay Ecological Corridor, reflecting the high importance of this area for conservation and understanding of evolution processes in the area, suggesting a probably adaptive radiation zone for the P. anaiae species group.