Two size classes of A. georgiana have been described in by-catch fishing data reported in the catch data from the Ross Sea fisheries. We extracted DNA from A. georgiana samples from both size classes collected by Scientific Observers in the Ross Sea. We determined the DNA sequences of five mitochondrial DNA (mtDNA) gene sequences and tested whether the two size classes represented genetically differentiated groups, which might have formed through a recent speciation event. We found no genetic differences among the samples of A. georgiana that were collected in the Ross Sea region, and the data did not support the hypothesis that the two size classes were reproductively isolated.
Sarah Mackey (CCAMLR Secretariat)