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Comparative population genetics and evolutionary history of two commonly misidentified billfishes of management and conservation concern.

ABSTRACT: BACKGROUND:Misidentifications between exploited species may lead to inaccuracies in population assessments, with potentially irreversible conservation ramifications if overexploitation of either species is occurring. A notable showcase is provided by the realization that the roundscale spearfish (Tetrapturus georgii), a recently validated species, has been historically misidentified as the morphologically very similar and severely overfished white marlin (Kajikia albida) (IUCN listing: Vulnerable). In effect, no information exists on the population status and evolutionary history of the enigmatic roundscale spearfish, a large, highly vagile and broadly distributed pelagic species. We provide the first population genetic evaluation of the roundscale spearfish, utilizing nuclear microsatellite and mitochondrial DNA sequence markers. Furthermore, we re-evaluated existing white marlin mitochondrial genetic data and present our findings in a comparative context to the roundscale spearfish. RESULTS:Microsatellite and mitochondrial (control region) DNA markers provided mixed evidence for roundscale spearfish population differentiation between the western north and south Atlantic regions, depending on marker-statistical analysis combination used. Mitochondrial DNA analyses provided strong signals of historical population growth for both white marlin and roundscale spearfish, but higher genetic diversity and effective female population size (1.5-1.9X) for white marlin. CONCLUSIONS:The equivocal indications of roundscale spearfish population structure, combined with a smaller effective female population size compared to the white marlin, already a species of concern, suggests that a species-specific and precautionary management strategy recognizing two management units is prudent for this newly validated billfish.

SUBMITTER: Bernard AM

PROVIDER: S-EPMC4278234 | biostudies-literature | 2014 Dec

REPOSITORIES: biostudies-literature

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Comparative population genetics and evolutionary history of two commonly misidentified billfishes of management and conservation concern.

Bernard Andrea M AM Shivji Mahmood S MS Prince Eric D ED Hazin Fabio H V FH Arocha Freddy F Domingo Andres A Feldheim Kevin A KA

BMC genetics 20141214

<h4>Background</h4>Misidentifications between exploited species may lead to inaccuracies in population assessments, with potentially irreversible conservation ramifications if overexploitation of either species is occurring. A notable showcase is provided by the realization that the roundscale spearfish (Tetrapturus georgii), a recently validated species, has been historically misidentified as the morphologically very similar and severely overfished white marlin (Kajikia albida) (IUCN listing: V ...[more]

PMID: 25494814

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Dataset Information

Comparative population genetics and evolutionary history of two commonly misidentified billfishes of management and conservation concern.

Publications

Comparative population genetics and evolutionary history of two commonly misidentified billfishes of management and conservation concern.

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