Recent Cytogenetic findings for the east Atlantic peacock wrasse, Symphodus tinca (Labridae, Teleostei), rarely observed in the Black Sea: Analysis of constitutive heterochromatin and rDNA gene regions

This study employed a 3-hour in vitro method using PB-MAX culture medium on kidney tissues from a rare East Atlantic peacock wrasse, Symphodus tinca (Linnaeus, 1758), collected from the Black Sea (Fatsa Bay, Ordu). The specimen was obtained as a single fish caught in a fisherman's net. Slide preparations were made by standard air-drying. High-quality metaphase slides were subjected to conventional C-banding, AgNO3 staining, and GTG-banding, with various modifications. Metaphases were karyotyped using AKAS Multispecies software, and idiograms were generated. Analysis of metaphase chromosomes revealed a common 2n=48 (NF=74) karyotype, with 6 metacentric, 20 submetacentric, 14 subtelocentric, and 8 acrocentric chromosomes. Sequential conventional staining first identified C+, NOR+, and G+ chromosome regions. These findings will support future molecular cytogenetic research, particularly regarding chromosomal evolution, genome differences within and between species, and taxonomic classification.