Unveiling the evolutionary relationships and the high cryptic diversity in Andean rainfrogs (Craugastoridae: group).

BACKGROUND

is the most diverse genus of terrestrial frogs. Historically, it has been divided into several phenetic groups in order to facilitate species identification. However, in light of phylogenetic analysis, many of these groups have been shown to be non-monophyletic, denoting a high degree of morphological convergence and limited number of diagnostic traits. In this study, we focus on the group, an assemblage of small rainfrogs distributed throughout the Andes of Ecuador and Colombia, whose external morphology is highly conserved, and its species diversity and evolutionary relationships largely unknown.

METHODS

We inferred a new phylogenetic hypothesis for the frog genus , including all available sequences of the mtDNA 16S rRNA, as well as new DNA sequences from 175 specimens. Our sampling included 19 of the 24 species currently recognized as part of the group.

RESULTS

Our new evolutionary hypothesis recovered the group as non-monophyletic and composed of 16 species. Therefore, we exclude and in order to preserve the monophyly of the group. We discovered at least eight candidate species, most of them hidden under the names of , and .

DISCUSSION

Our results reveal the occurrence of a high level of cryptic diversity to the species level within the group and highlight the need to redefine some of its species and reassess their conservation status. We suggest that the conservation status of six species within the group need to be re-evaluated because they exhibit smaller distributions than previously thought; these species are: , and . Finally, given that the group, as defined in this work, is monophyletic and morphologically diagnosable, and that is an available name for the clade containing , we implement as a formal subgenus name for the group.