Biogeografia histórica, diversidade, sistemática e conservação do grupo Pristimantis unistrigatus (Anura: Strabomantidae)

Abstract

The genus Pristimantis is the richest in number of species among vertebrates and, even so, its diversity is highly underestimated. These anurans are widely distributed throughout the Neotropical region and due to their generally restricted ecological niches, low vagility and reproductive biology, they represent an interesting model for biogeographic studies. The P. unistrigatus species group is non-monophyletic and has been defined solely based on its morphology. Thus, the present thesis has as its central approach the underestimated megadiversity of the group's species, their biogeographic history, composition, systematics, and insights for their conservation. In Chapter I, using DNA sequences of three mitochondrial and two nuclear loci from 416 specimens throughout the range of the group and including 68 nominal species, we assessed the species boundaries and distribution of the group, and to infer spatiotemporal patterns of diversification related to landscape changes in the Neotropics. We redefine the group based on the phylogeny and found 151 OTUs that composes it, with 83 of these remaining undescribed. We recovered 11 major clades within the group that diverged before 13 Ma. The Northwestern South America currently corresponding to western Amazonia and Northern Andes, is the most likely origin of the group in the Early Miocene. The other neotropical areas acted as sinks, receiving lineages mostly during the last 10 Ma, after the demise of the Pebas System and the setup of the modern Amazonian hydrography. This approach is similar to the biogeographic history of other Neotropical amphibians. In Chapter II, we provide an amended diagnosis of P. ockendeni based on external morphology and advertisement call of specimens recently collected nearby the type locality and additional localities in southwestern Amazonia. After this, we evaluated the taxonomic status of populations historically identified as P. ockendeni occurring in the Guiana Shield, confirmed them as a new species and formally described it, attributing information on morphology, osteology, phylogenetic position, bioacoustics, ecology, distribution, and its natural history. In Chapter III, we discovered and described a new species apparently endemic to the white sand forests of the Negro-Solimões interfluve and, with morphological, molecular, and acoustic data, we recognized its phylogenetic position, geographic distribution, provided natural history data and highlighted the need effective protection of this ecosystem. Finally, the study of the diversity and composition of the Pristimantis unistrigatus group allowed the recognition of several candidate species. Our results provide perspectives for studies on the ecology, diversification, and taxonomy of the group, providing insights that will help advance biological knowledge about various species complexes and, in the future, delimit the conservation status of these species.