Presence of unexpected phylogenetic lineages of brown trout Salmo trutta L. in Gacka River, Croatia

Abstract

This study provides the first analysis of mtDNA control region variation of brown trout samples from the Gacka River, in order to assess their phylogenetic lineage affliation and address the question of the origin of phylogenetic haplotypes in the river. Aligned sequences from 21 individuals were sorted into two haplotypes. Based on the 334 bp fragment at the 50'end of the control region, 14 fish were assigned to the Danubian lineage (67%) and seven were assigned to the AT lineage (33%). All fish assigned to the Danubian lineage revealed just one haplotype: Da2 (M97975). The same was observed within the AT lineage-assigned fish, where only one haplotype, At1 (M97969), was found.The prevalence of Danubian haplotype and no finding of Adriatic haplotype imply an autochthonous status of the Danubian haplotype in Gacka River.