MOLECULAR TAXONOMIC STUDY OF HORSE MACKEREL (TRACHURUS MEDITERRANEUS) USING ITS1 VARIABILITY

Carangidae is a family of marine, mostly predatory fishes, which comprises of species like jacks, pompanos, jack mackerels and scads. Several of them are subject of commercial fishing. In Black Sea Carangidae is represented by two species: Trachurus trachurus and T. mediterraneus. The Mediterranean horse mackerel (Trachurus mediterraneus) is subject of commercial fishing. The economical importance of the horse mackerel and the need of adequate measures for conservation and proper management of its resources in the Black Sea require more information about the population dynamics and biodiversity of that species. In this study the applicability of ITS1 sequences for molecular taxonomy studies of horse mackerel was assessed. For this purpose genomic DNA was isolated from ten samples caught in different Bulgarian coastal areas. It was used as a template for PCR amplification of the ITS1 regions. The results presented on the general phylogenic tree allowed us to distinguish two subclusters. The first one comprises of the samples caught during the summer in the Northern coastal region and during the winter from the Southern coastal regions, while the second consist of samples captured during the winter and spring from Northern regions. Probably this division corresponds with the existence of at least two populations of Mediterranean horse mackerel (Trachurus mediterraneus) in Bulgarian costal region that migrate during different seasons from North to South and back.