Sažetak Endemic soft-muzzled trout (Salmo obtusirostris salonitana) inhabit the Jadro River, near Split. Part of the population has been translocated to the Žrnovnica River and belongs to the Salmonidae family, genus Salmothymus. It has a very restricted distribution, so any interference with its habitat has a negative influence on this small population. Soft-muzzled trout populations are constantly threatened by many factors. In waters where soft-muzzled lives beside thetrout, the existence of hybrids has been recorded. Using genetic markers population structure of endemic soft-muzzled trouts from Jadro and Žrnovnica rivers has been defined. Solinka is defined as a naturally brid species, the result of ancient hybridization of original shape soft-muzzled trout (S. ooxyrhynchus) with more advanced brown trout (S. trutta).