C-banded karyotype and nucleolar organizer regions of Tinca tinca (Cyprinidae) from Turkey

In this study, conventional Giemsa staining, Silver-Nucleolar Organizer Region (Ag-NOR) and C-banding were applied to eight specimens of Tench, Tinca tinca, of Lake Beyşehir, and their detailed cytogenetic properties were investigated. It was determined that all of the chromosomes in karyotypes of the samples investigated were bi-armed (metacentric, submetacentric, subtelocentric). Also a secondary constriction was observed on the short arm of the third pair of chromosomes. No morphological difference was identified between sex chromosomes of male and female specimens. All chromosomes of the specimens had centromeric and pericentromeric C-bands. There was an interstitial band on the short arm of a chromosome pair, while all the short arms of three chromosome pairs were C-positive. Heteromorph C-bands were detected in two chromosome pairs. By Ag-nitrate staining, active NOR was identified on the short arm of the number three metacentric chromosome pair of all specimens. However, this active NOR was not related to C-heterochromatin. All the active NORs determined in the studied specimens were homomorphisms. © 2012 Dipartimento di Biologia Evoluzionistica, Università di Firenze.