Demographic history and population structure of Notropis suttkusi in southeastern Oklahoma

Authors: Michael R. Schwemm, Anthony A. Echelle, Ronald A. Van Den Bussche

Year: 2012 (xliv)

Abstract

Recent phylogeographic analyses have shown that the Rocky Shiner Notropis suttkusi of southeastern Oklahoma and southwestern Arkansas represents a distinct clade of the widespread N. rubellus complex. This species is of conservation concern because of proposed water development projects on the Arbuckle aquifer. Our results are interpreted against the broader geographic perspective of previous genetic analyses and provide insight into conservation genetics for the species. Here, we present results from a population genetic analysis using complete sequences of the mitochondrial cytochrome b gene from five populations throughout the species’ range. Results show large numbers of weakly divergent haplotypes (60 in 178 fish; <1.1% divergence). Haplotype diversity was low (0.12) in the population examined from Muddy Boggy River (McGee Creek), high in Blue River (0.74) and unusually high in the populations from the Kiamichi, Little, and Glover rivers (0.93-0.97). Instances of high haplotype diversity were due to large numbers of private haplotypes. This suggests that populations in different streams are isolated and demographically independent. Additionally, nucleotide divergences indicate contrasting demographic patterns among Red River tributaries. Results from mismatch distributions show that the population from Blue River has been stable in population size, while other tributaries indicate a pattern of late Pleistocene expansion. These patterns highlight the importance of the Blue River in the history of the species.