Evolutionary relationships amongst polymorphic direct-developing frogs in the Craugastor rhodopis Species Group (Anura: Craugastoridae)

Abstract

The Craugastor rhodopis Species Group includes two leaf-litter frog species (C. loki and C. rhodopis). These direct-developing frogs inhabit tropical regions of Mexico and northern Central America. Characterizing diversity within the group has been difficult due to high levels of phenotypic polymorphism within and between species. Because of these polymorphisms, each taxon has junior synonyms. Using a fragment of mitochondrial DNA (mtDNA), we investigated genetic diversity in the C. rhodopis Species Group. We then examined type specimens (including types of junior synonyms) to match nomenclature to geographically circumscribed genetic clusters. Our molecular analyses revealed four major lineages within the C. rhodopis Species Group: (1) a widely distributed clade in western Mexico, (2) a highland clade in eastern Mexico, (3) a widely distributed lowland clade occurring in eastern Mexico, Guatemala and El Salvador, and (4) a haplotype from Volcán San Martín in Veracruz, Mexico. We identified the first clade as C. occidentalis, a taxon currently placed in the ecologically similar but phylogenetically distant C. mexicanus Species Series. In light of this we place C. occidentalis in the C. rhodopis Species Group and designate a lectotype and paralectotype for the species. The second and third clades inhabiting eastern Mexico and northern Central America correspond to C. rhodopis and C. loki, respectively. Additionally, we examined the taxonomic distribution of certain colour pattern traits and compensatory mutations in Domain III of the mtDNA 12S ribosomal RNA gene. Our recovery of the divergent Veracruz haplotype and extensive mtDNA structure within species indicates that additional taxonomic revision will be necessary.

Key words:

• amphibian
• colour pattern polymorphism
• Eleutherodactylus
• Mesoamerica
• phylogeography
• Terrarana

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Corrigendum

Acknowledgements

We thank the following individuals (and their respective institutions) for allowing access to specimens in their care: A. Resetar, T. F. Lian and R. Inger (FMNH), A. Wynn, R. Heyer and R. Wilson (USNM), B. Clarke, D. Gower and M. Wilkinson (BMNH), C. Phillips and M. Dreslik (INMH), R. Brown and A. Campbell (KU). M. Ingrasci kindly photographed museum specimens at FMNH. We are indebted to many individuals who assisted us with field and laboratory work during the course of this investigation. E. Greenbaum greatly aided this study by his donation of material from El Salvador. J. C. Arenas and E. Wostl provided helpful comments on early drafts of the manuscript. The following individuals helped by collecting leaf-litter frogs for this study: L. Canseco-Márquez, C. Vásquez-Almazán, C. Cox, C. Sheehy III, T. Eimermacher, C. Franklin, M. Vaughn, R. Tovar, M. Ingrasci, J. Reyes-Velasco, G. Weatherman, T. Devitt, R. Garcia-Anleu, A. Carbajal Saucedo, F. R. Mendoza Paz, M. E. Acevedo, J. L. Camarillo Rangel and J. Meik. We thank B. Barker for discussions on Eleutherodactylus colour pattern polymorphism.

Associate Editor: Christoph Bleidorn

Additional information

Funding

Funding was provided by NSF grants to JAC [DEB-0613802 & 0102383] and a Bioclon grant to ENS, CONACYT [no. 47590-Q], and DGAPA, UNAM [PAPIIT no. IN 224009] to A. Nieto-Montes de Oca. We thank two anonymous reviewers for comments that greatly enhanced the quality of the manuscript.