Trout Salmo spp. complex in Serbia and adjacent regions of the western Balkans: reconstruction of evolutionary history from external morphology

The multivariate phenetic approach to the classification of Salmo spp. samples from Serbia and adjacent regions of western Balkans for 22 continuous external morphological characters suggests the occurrence of the following distinct stocks: West Danubian (Crno Osoje Stream and upper Zeta River) Salmo taleri , marble trout Salmo marmoratus (Trebuščica River), hatchery-reared Atlantic Salmo trutta , Mlava River drainage (Mlava and Krupaja rivers and Buk Stream) trout Salmo cf. trutta , Velika Morava River system (Godljevača, Bela and Resava rivers) trout S. cf. trutta , Ohrid Lake belvica Salmo ohridana and Aegean coastal drainage Salmo macedonicus (Božica River). In contrast to the phenetic similarity, the phylogenetic reconstruction places the Lake Ohrid belvica as part of an unresolved polytomy with other trout groups. Salmo cf. trutta in the Mlava River appears to form the basal group for the trout species in the region. The position of marble trout implies its independent and more recent origin from the West Danubian trout stock.