Conservation Genetics

, Volume 13, Issue 2, pp 443–454 | Cite as

Conservation genetics of an endemic mountaintop salamander with an extremely limited range

  • Claire S. O. Bayer
  • Andrew M. Sackman
  • Kelly Bezold
  • Paul R. Cabe
  • David M. MarshEmail author
Research Article


Montane regions can promote allopatric speciation and harbor unique species with small ranges. The southern Appalachians are a biodiversity hotspot for salamanders, and several montane endemics occur in the region. Here, we present the first DNA sequence data for Plethodon sherando, a terrestrial salamander recently discovered in the Blue Ridge Mountains of Virginia. We sequenced two mitochondrial regions (cyt-b and CO1) from salamanders at reference sites near the center of P. sherando’s range and from two contact zones where P. sherando populations are replaced by Plethodon cinereus, the Northern Red-Backed salamander. We then used these sequence data to examine divergence and hybridization between the two taxa. We found P. sherando and P. cinereus morphotypes from contact zones to be reciprocally monophyletic and highly divergent (~17%). P. sherando exhibited very low sequence diversity (π = 0.0010) as compared to P. cinereus from the same locations (π = 0.0096). Salamander morphology in the contact zone was as distinct as morphology at reference sites, and discriminant function analysis based on morphology successfully classified 98% of salamanders to their mitochondrial lineage. Phylogenetic analysis of cyt-b sequences showed P. sherando to be sister to Plethodon serratus (the Southern Red-Backed salamander) rather than P. cinereus or any nearby mountaintop endemics. Our results suggest that P. sherando is a distinct lineage that is not subject to substantial introgression from P. cinereus and that may have a history of geographic isolation. Given its limited range (<80 km2), we believe P. sherando should merit a conservation status similar to that of other mountaintop salamanders in the region.


Plethodonsherando Big Levels salamander Plethodon cinereus mtDNA Phylogeography Population genetics 



We thank Shane Ramee and members of the 2009 Field Herpetology class for help with collecting salamanders. Briana Gregory and Woodrow Friend assisted with DNA extractions and Jennifer Schieltz and Caroline Bovay contributed to the GIS analysis. We thank Richard Highton, Nadia Ayoub, and two anonymous reviewers for helpful comments on earlier drafts of this manuscript. This research was covered by Virginia state collection permit #33510 and IACUC animal care and use permit DM0109. Financial support for this study was provided by the U.S. Forest Service, a Howard Hughes Medical Institute award to Washington & Lee University under the Undergraduate Science Education Program, and an H. F. Lenfest grant to D Marsh.


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Copyright information

© Springer Science+Business Media B.V. 2011

Authors and Affiliations

  • Claire S. O. Bayer
    • 1
  • Andrew M. Sackman
    • 1
  • Kelly Bezold
    • 1
  • Paul R. Cabe
    • 1
  • David M. Marsh
    • 1
    Email author
  1. 1.Department of BiologyWashington and Lee UniversityLexingtonUSA

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