Uncovering hidden specific diversity of Andean glassfrogs of the Centrolene buckleyi species complex (Anura: Centrolenidae).

Luis Amador,Andrés Parada,Juan M Guayasamin,Guillermo D’Elía

doi:10.7717/peerj.5856

Abstract

The glassfrog Centrolene buckleyi has been recognized as a species complex. Herein, using coalescence-based species delimitation methods, we evaluate the specific diversity within this taxon. Four coalescence approaches (generalized mixed Yule coalescents, Bayesian general mixed Yule-coalescent, Poisson tree processes, and Bayesian Poisson tree processes) were consistent with the delimitation results, identifying four lineages within what is currently recognized as C. buckleyi. We propose three new candidate species that should be tested with nuclear markers, morphological, and behavioral data. In the meantime, for conservation purposes, candidate species should be considered evolutionary significant units, in light of observed population crashes in the C. buckleyi species complex. Finally, our results support the validity of C. venezuelense, formerly considered as a subspecies of C. buckleyi.

Highlights

Species delimitation—the process by which species boundaries are determined—is important and a challenge for characterizing the biota of biodiversity hotspots (Myers et al, 2000)
The methods of phylogenetic reconstruction (ML and Bayesian inference (BI)) inferred identical evolutionary relationships, in particular regarding the lineages of the C. buckleyi species complex (Fig. 2)
The C. buckleyi species complex is not recovered as monophyletic; sequences recovered from specimens of C. buckleyi form four main lineages, namely C. buckleyi sensu stricto, C. buckleyi [Ca1], C. buckleyi [Ca2], and C. aff. buckleyi [Ca3] (Fig. 2)

Summary

Introduction

Species delimitation—the process by which species boundaries are determined—is important and a challenge for characterizing the biota of biodiversity hotspots (Myers et al, 2000). Coalescent-based methods, which allow testing alternative hypotheses on the divergence of a lineage, are expected to reduce the subjective bias introduced by researchers, avoiding using ad hoc thresholds (i.e., degree of morphological, ecological, and/or percentage of sequence divergence) as criteria to establish species limits. As such, these methods have become a common tool for delimiting species, both to propose candidate species as well as to describe new species (Leaché & Fujita, 2010; Páez-Moscoso & Guayasamin, 2012; Crivellaro et al, 2018). Conclusive species delimitation studies must have an integrative approach (Dayrat, 2005; Padial et al, 2010)

Methods

Results

Discussion

Conclusion