High Species Richness of Scinax Treefrogs (Hylidae) in a Threatened Amazonian Landscape Revealed by an Integrative Approach.

Miquéias Ferrão,Albertina P Lima,Jiří Moravec,Olavo Colatreli,Igor L Kaefer,Rafael De Fraga,William J Etges

doi:10.1371/journal.pone.0165679

Abstract

Rising habitat loss is one of the main drivers of the global amphibian decline. Nevertheless, knowledge of amphibian diversity needed for effective habitat protection is still highly inadequate in remote tropical regions, the greater part of the Amazonia. In this study we integrated molecular, morphological and bioacoustic evidence to evaluate the species richness of the treefrogs genus Scinax over a 1000 km transect across rainforest of the Purus-Madeira interfluve, and along the east bank of the upper Madeira river, Brazilian Amazonia. Analysis revealed that 82% of the regional species richness of Scinax is still undescribed; two nominal species, seven confirmed candidate species, two unconfirmed candidate species, and one deep conspecific lineage were detected in the study area. DNA barcoding based analysis of the 16s rRNA gene indicates possible existence of three discrete species groups within the genus Scinax, in addition to the already-known S. rostratus species Group. Quantifying and characterizing the number of undescribed Scinax taxa on a regional scale, we provide a framework for future taxonomic study in Amazonia. These findings indicate that the level to which Amazonian anura species richness has been underestimated is far greater than expected. Consequently, special attention should be paid both to taxonomic studies and protection of the still-neglected Amazonian Scinax treefrogs.

Highlights

Frogs achieve mega-diversity in the tropics, but this extreme species richness is under strong pressure from human disturbance, mainly via habitat loss and degradation of breeding sites [1]
The northern portion of Purus and Madeira rivers (PMIR) is covered by tropical lowland rainforest with emergent canopy, while open lowland rainforest with palm trees occurs in the southern portion of PMIR and eastern bank of the upper Madeira (EBMR) ([28], Fig 1A)
For the data set involving all putative units in the Maximum Clade Credibility (MCC) tree, and using the candidate species proposed by [7, 66] as a reference, Automatic Barcoding Gap Discovery (ABGD) showed greater accuracy in defining the candidate species when compared to Generalized Mixed Yule Coalescent (GMYC), as this letter method tended to group two or more candidate species

Summary

Introduction

Frogs achieve mega-diversity in the tropics, but this extreme species richness is under strong pressure from human disturbance, mainly via habitat loss and degradation of breeding sites [1]. It is becoming increasingly evident that the diversity of frogs has been. High Species Richness of Scinax in Brazilian Amazonia (CENBAM). Miqueias Ferrão receives a PhD scholarship from the Fundacão de Amparo à Pesquisa do Estado do Amazonas (FAPEAM). Rafael de Fraga had a PhD scholarship from the Coordenacão de Aperfeicoamento de Pessoal de Nıvel Superior (CAPES). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript

Methods

Results

Conclusion