Evaluating the genetic purity of relict dace populations in the central Great Basin

Authors: Derek D. Houston, R. Paul Evans, Dennis K. Shiozawa

Year: 2010 (xlii)

Abstract

The relict dace, Relictus solitarius, is a Great Basin endemic minnow restricted to a few spring systems within the Butte, Goshute, Ruby, and Steptoe basins in eastern Nevada. These aquatic habitats are remnants of pluvial lakes that filled those basins during the Pleistocene. Relictus solitarius is the only native fish in these basins, but speckled dace, Rhinichthys osculus, has been introduced into some of the localities. We used mitochondrial DNA (mtDNA) sequence data in an attempt to determine if four putative relict dace populations in Ruby Valley share mitochondrial haplotypes with speckled dace. Shared mitochondrial haplotypes could result from introgression of the mitochondrial genome following hybridization between the two species. Preliminary results of phylogenetic analyses show that relict dace mtDNA sequences from the Ruby Valley populations are more closely related to speckled dace than to relict dace, suggesting that mitochondrial introgression has occurred.