• DOI:10.1674/0003-0031(1998)140[0096:MDVIJD]2.0.CO;2
• Corpus ID: 86021258

Mitochondrial DNA Variation in Johnny Darters (Pisces: Percidae) from Eastern Kentucky Supports Stream Capture for the Origin of Upper Cumberland River Fishes

@inproceedings{Strange1998MitochondrialDV,
  title={Mitochondrial DNA Variation in Johnny Darters (Pisces: Percidae) from Eastern Kentucky Supports Stream Capture for the Origin of Upper Cumberland River Fishes},
  author={Rex Meade Strange},
  year={1998}
}

• R. M. Strange
• Published 1 July 1998
• Environmental Science

Abstract The Poor Fork of the Cumberland River has been interpreted as an area of secondary contact and hybridization between Etheostoma nigrum and the closely related E. susanae. I examined mitochondrial DNA (mtDNA) diversity among E. nigrum populations in the adjacent Kentucky River drainage, E. susanae populations in the Cumberland River drainage, and the population of E. nigrum occurring in the putative hybrid zone of the Poor Fork. Fifteen restriction enzymes revealed the presence of four mtDNA haplotypes, two each in the Kentucky and Cumberland rivers. Etheostoma nigrum from the Kentucky River had two haplotypes (K1 and K2), which differed by a single restriction site. All E. susanae from the Cumberland River had a distinctive haplotype (S1), while E. nigrum from the upper Poor Fork had a unique haplotype (CN1). Johnny darters from the upper Poor Fork of the Cumberland River were phenotypically and genetically more similar to E. nigrum populations in tributaries of the upper Kentucky River than to E. susanae, and were probably introduced by stream capture. Implications of this distribution pattern include: (1) that more than one event or mechanism was responsible for the isolation of fishes in the upper Cumberland River, and (2) that conservation efforts for E. susanae should focus on habitats occurring immediately above Cumberland Falls rather than in the contact zone in the Poor Fork.