Exploring Mitochondrial Evolutionary Pathways: Insights into the Origin of the Endemic Ohrid Trout.

The Ohrid trout, , is an endemic species of Lake Ohrid, one of Europe's oldest lakes, located on the Albania-North Macedonia border. This species exhibits distinct morphotypes-, , , and -that differ in morphology and spawning behaviour. However, the extent of their genetic differentiation remains unclear. This study aimed to investigate the genetic variability and population structure of morphotypes using the mitochondrial Control Region as molecular marker. We obtained 127 sequences from morphotypes and compared them with sequences from other species within the genus . Phylogenetic and clustering analyses revealed no significant genetic structuring among the four morphotypes, suggesting an ecological differentiation not (yet) fixed at mitochondrial level. Additionally, our findings suggest that the modern population likely originated in Lake Ohrid from founders through evolutionary differentiation, potentially driven by environmental changes. Future studies incorporating a larger number of samples from both and are essential to fully understand the evolutionary and ecological dynamics of morphotypes.