DOI: 10.5061/dryad.5x69p8d1s
title: Conservation genetic assessment of the paleback darter (Etheostoma pallididorsum), a narrowly distributed endemic in the Ouachita Highlands, Arkansas, USA

description: The Paleback Darter is considered imperiled and has recently been
 petitioned for listing under the Endangered Species Act. Prior
 allozyme-based studies found evidence of small effective population size,
 warranting conservation concern. The objective of this study was to assess
 population dynamics and the phylogeographic history of the Paleback
 Darter, using a multilocus microsatellite approach and mitochondrial DNA.
 The predictions of this study were that Paleback Darter populations will
 exhibit low genetic diversity and minimal gene flow; population structure
 will correspond to river systems where samples are derived; the reservoir
 dams impounding the reaches between the Caddo and Ouachita rivers would
 serve as effective barriers to gene flow; and the Caddo and Ouachita
 rivers are reciprocally monophyletic. Microsatellite DNA loci revealed
 significant structure among sampled localities (global Fst = 0.17, P
 &lt; 0.001), with evidence of two distinct populations representing
 the Caddo and Ouachita rivers. However, Bayesian phylogeographic analyses
 resulted in three distinct clades, Caddo River, Ouachita River, and Mazarn
 Creek. Divergence from the most recent ancestor shared among the river
 drainages was estimated at 60-KYA. Population genetic diversity was
 relatively low (He = 0.65; mean alleles per locus [A] = 6.26), but
 comparable to close relatives, Slackwater Darter (He = 0.65; A = 6.74) and
 Tuscumbia Darter (He = 0.57; A = 5.53). These results have conservation
 implications for Paleback Darter populations and can be informative for
 other headwater specialist species. Like other headwater species with
 population structuring and relatively low genetic diversity, persistence
 of Paleback Darter populations is likely tied to persistence and
 connectivity of local breeding and non-breeding habitat. These results do
 not raise conservation concern for a population decline; however, the
 restricted distribution and endemic status of the species still renders
 Paleback Darter populations vulnerable to extirpation or extinction.
description: Tissue samples were collected from up to 30 Paleback Darter
 individuals per locality throughout the Ouachita River basin in
 southwestern Arkansas. A total of 181 individuals were successfully
 genotyped for 8 microsatellite DNA loci, with primers designed for the
 Greenside, Candy, Rainbow, Cherokee, and Orangethroat darters. Up to 10
 individuals per sub-drainage were additionally amplified for the
 mitochondrial cytochrome <em>b</em> gene
 (cyt <em>b</em>). The cyt <em>b </em>sequences
 were accessioned with GenBank.
description: <strong>Microsatellite data GENEPOP
 format</strong>
 <em>PalebackDarter_Genepop.txt</em>
 The microsatellite DNA data file is in GENEPOP format. The file
 includes genotype scores for 8 microsatellite loci for the Paleback
 Darter. Locus names are listed under the title line at the top of the
 file. POP refers to populations described in the manuscript. The
 populations are ordered as follows: (1) Caddo River; (2) tributary to the
 Caddo River, Polk Creek; (3) tributary to the Caddo River, Lick Creek; (4)
 tributary to the Ouachita River, Big Fork Creek; (5) tributary to the
 Ouachita River, Kate's Creek; (6) tributary to the Ouachita River,
 Big Hill Creek; (7) tributary to the Caddo River, Collier Creek; (8)
 tributary to the Ouachita River, Mazarn Creek. Each row below POP
 identifiers represents an individual followed by their genotype for the
 8 loci. Individual identifiers and specimen information can be found in
 the associated excel file named "PalebackSpecimenInfo.xlsx".
 Allele scores for each locus are concatenated into six digits, with the
 first three numbers representing the size of allele one and the second
 three numbers representing the size of allele two. Missing data are coded
 as "000". <strong>Specimen
 Information</strong>
 <em>PalebackSpecimenInfo.xlsx</em>
 Detailed information for Paleback Darter samples used in this
 study. Museum tissue catalog or specimen voucher catalog numbers are
 followed by individual identifiers and collection locality information.
 Specimens and/or tissues were cataloged in the Arkansas State University
 Museum of Zoology (ASUMZ) in the Arkansas Center for Biodiversity
 Collections.