Evolutionary associations between sand seatrout (Cynoscion arenarius) and silver seatrout (C. nothus) inferred from morphological characters, mitochondrial DNA, and microsatellite markers

• Main Authors: Anderson, Joel D., McDonald, Dusty L., Sutton, Glen R., Karel, William J.
• Format: Article in Journal/Newspaper
• Language: English
• Published: 2009
• Subjects: Biology; Ecology; Fisheries; Red drum; Sciaenops ocellatus
• Online Access: http://aquaticcommons.org/8808/; http://fishbull.noaa.gov/1071/anderson.pdf; http://aquaticcommons.org/8808/1/anderson_Fish_Bull_2009.pdf

The evolutionary associations between closely related fish species, both contemporary and historical, are frequently assessed by using molecular markers, such as microsatellites. Here, the presence and variability of microsatellite loci in two closely related species of marine fishes, sand seatrout (Cynoscion arenarius) and silver seatrout (C. nothus), are explored by using heterologous primers from red drum (Sciaenops ocellatus). Data from these loci are used in conjunction with morphological characters and mitochondrial DNA haplotypes to explore the extent of genetic exchange between species offshore of Galveston Bay, TX. Despite seasonal overlap in distribution, low genetic divergence at microsatellite loci, and similar life history parameters of C. arenarius and C. nothus, all three data sets indicated that hybridization between these species does not occur or occurs only rarely and that historical admixture in Galveston Bay after divergence between these species was unlikely. These results shed light upon the evolutionary history of these fishes and highlight the genetic properties of each species that are influenced by their life history and ecology.